Framebuilding Info
A couple of summers ago [note: this was written nearly 10 years ago!], I got involved in my first attempt at framebuilding/modification.
I tried converting a normal rigid MTB frame into a rear-suspension frame.
I started with a 1988 Schwinn Sierra MTB frame that I got new for the nice
low price of $25, and it's even full chromoly! For the spring unit, I used
ProFlex MCU's. I used ball joints for all pivots.
A lot of the online information on brazing that I received
from several helpful people is presented below.
The frame hopefully will look something like this when finished:
Note: Not to scale
Long Overdue Update:
Well, I finished the bike about a year ago, and just never got around to scanning photos. The project was a success in someways and a failure in others...namely, though I got the bike together and actually rode it a bit, the rear end proved to be much too flexible and bent easily. It needs to be strengthened/reinforced. I have a couple of ideas on how to do that, but I lost my brazing-friendly workspace before I could try any of them out. I recently moved into a house with a garage and backyard, and very well may try to recussitate this frame, which has been hanging on the wall for the past 2 years...the parts you see in the accompanying photos were transplanted onto an '89 Rockhopper frame, since I had dumped more money than planned into getting that old M3 fork functional, and I was damn well gonna get some use out of it!
Well, here's the bike.
And, just to prove that I did indeed actually ride this thing, here's proof.
Here are some construction details. The following picture shows how I used ball joints
to form the main pivot. The cut ends of the chainstays were slotted and crimped together,
and nuts were brazed in the ends. The ball joints thread into the nuts, and an additional
nut on each ball joint serves as a locknut. The stubs of chainstay left on the bottom bracket
were reinforced by silver-brazing 2 oval 'plates', formed from bike-frame tubing, to each
outside edge. A hole was then drilled horizontally through each chainstay stub, and then the
stubs were slotted by dilligent application of various files and a hacksaw to accept the
round end of the ball joint. A bolt, a nut, and a couple of plastic shims for each chainstay
complete the assembly.
As you can see, the only thing holding the two chainstays together is the brake bridge. Since the chainstays are no longer rigidly attatched to the BB shell, they are more-or-less free to now also move in a horizontal plane...the only things attempting to prevent them from doing this are the brakebridge and the rear axle, clamped into the rear dropouts. A bent brake bridge and a tweaked rear axle were proof that things weren't strong enough. Shortly after these photos were taken, I purchased a bolt-on cantilever brake adaptor, which lets you mount canti's on a frame or fork that doesn't have braze-ons for them. This thing is a U-shaped piece of 1/2" tubular steel with a hole at the bottom of the U for a brake-bridge (or fork) mounting bolt, and canti studs welded on the other side. My current plan is to remove the canti studs and braze this U onto the chainstays to stiffen things up. Problem here is that under the chainstays is the U-brake, and over the chainstays is the front derailleur...basically there's not enough room for this thing...a U-shaped piece cut out of plate steel would be better, since it'd be thinner, and it'd fit between the top of the chainstays and the front derailleur.
An alternate idea is to just remove the brake bridge altogether, and replace it with a larger-diameter
section cut from a top tube or a down tube. The idea here is that the larger-diameter tube
would be more resistant to bending and therefore stiffen things up. I am worried about the brazing
required for this solution, however, because it's close enough to the nuts brazed into the
ends of the chainstays to possibly melt their joints and allow them to shift, throwing things drastically
out of alignment.
Here's a closeup shot of the seatstay pivots, which were fabricated in much the same way
as the BB/chainstay pivots: A nut was brazed onto the cut end of the seatstay. Through this threads
a smaller ball joint, which attatches to a reinforced and slotted seatstay stub with a bolt and nut.
Lots more filing here.
These two photos provide some more detail on the rear spring assembly...remember it's taken
from a Proflex. The bottom photo shows how I fabricated the spring unit. A large washer (2" OD x
1/2" ID) was brazed to the upper stubs of the seatstays. A smaller washer and nut were brazed
up inbetween the "Y" formed by the stubs. Down at the other end, a 2-inch piece of downtube was brazed
between the seatstays, which were bent inwards and filed to meet it. Another washer was brazed to the
top of the assembly.
Inside the yellow MCUs is a hollow 1/2" aluminum slider tube. A 100mm bolt
runs up from the bottom of the spring through this tube and screws into the nut attatched between
the Y of the seatstay stubs. A small plastic bushing is mounted in the hole in the lower 2" washer
to reduce wear on the slider tube. Another washer is installed at the bottom end of the 100mm bolt to
act as a keeper--it prevents the spring from falling apart when the bike is picked up, or, dare I
say it, airborne. :)
Finally, this pic shows some of the tools I worked with. Note the orange milk crates--
the left one contains my torch, a Bernzomatic model with an extension hose, which was
designed so that the tank could be worn on your belt, allowing some mobility. I felt
better having the tank on the ground, so I hooked the belt hook over the edge of the
crate. The right-hand milkcrate is turned upside-down, and a small vise is bolted to
the bottom corner, with a couple of wooden reinforcement plates. This was my 'filing
seat', and even though I didn't have a proper work bench, it allowed me to clamp tubes and
cut or file the ends of them. On the ground next to the crates are my files, wire
brushes, sandpaper for prepping metal for brazing, and my el-cheapo hacksaw. Oh,
and between the crates is my pair of heavy leather $5 welding gloves.
Random Info
The following is pretty much all of the information I've received via email or from newsgroups (rec.crafts.metalworking, rec.bicycles.tech) on the subject of brazing and framebuilding. Someday, I hope to actually organize it!
Note: This section is highly under construction!
Article 73225 of rec.bicycles.tech: Path: newsfeed.pitt.edu!dsinc!spool.mu.edu!howland.reston.ans.net!news-e1a.megaweb.com!newstf01.news.aol.com!newsbf02.news.aol.com!not-for-mail From: dlearl@aol.com (D L EARL) Newsgroups: rec.bicycles.tech Subject: Re:Brass or Silver Date: 21 Feb 1996 14:53:56 -0500 Organization: America Online, Inc. (1-800-827-6364) Lines: 5 Sender: root@newsbf02.news.aol.com Message-ID: <4gft8k@newsbf02.news.aol.com> Reply-To: dlearl@aol.com (D L EARL) NNTP-Posting-Host: newsbf02.mail.aol.com Silver melt temp is considerably lower, therefore better from standpoint of heat damage to the tubes. Silver generally will not fill big gaps, that is why brass still often used with dropouts. Silver is only way to braze certain tubesets that will not tolerate heat required for brass (Reynolds 753 for example) Article 73871 of rec.bicycles.tech: Path: newsfeed.pitt.edu!scramble.lm.com!news.math.psu.edu!chi-news.cic.net!vixen.cso.uiuc.edu!newsfeed.internetmci.com!in1.uu.net!news.eden.com!arlut.utexas.edu!geraldo.cc.utexas.edu!lewis From: lewis@chaos.utexas.edu (Greg Lewis) Newsgroups: rec.bicycles.tech Subject: Re: brazing & burning paint Date: 28 Feb 1996 22:04:19 GMT Organization: Center for Nonlinear Dynamics Lines: 47 Message-ID: <4h2jh3@geraldo.cc.utexas.edu> References: <4h2bcg@usenet.srv.cis.pitt.edu> NNTP-Posting-Host: chaos.ph.utexas.edu X-Newsreader: TIN [version 1.2 PL2] Breathing paint fumes is always a bad idea. That said you probably won't do too much dammage to yourself if you have a decent breeze and stand upwind. Try to remove the paint in a large area around the lugs before you try to melt down the joints. Also the brazing material may be very different (particularly if it is a cheep bike) from what you will be using so this may not be the best practice. I'd recommend just getting some pieces of metal and try brazing them together. If you can get two steel tubes that telescope together with fairly close tolorances that would be ideal. If you can't try a 1-1/16 inch and one inch bike tube. Cut a ring off the end of the 1-1/16 tube and then cut a section off of it along the axis and bend it so that it is fairly snug on the 1 inch tube. James W Gourgoutis (skoop+@pitt.edu) wrote: : Okay...probably a stupid question, but I just want to be safe. I'm in : the process of learning how to braze, just got my torch last week, and : I'm going to start by melting down a frame or two into tubes and lugs to : get a feel for how the torch works. What I want to know is this: if I : do this outdoors (i.e. fairly well-ventilated area), am I in any danger : of harmful vapors from the burning paint? : I spent a long time sanding all the paint off the frame I *want* to : evenutally braze on...I'd rather not also have to remove the paint on my : practice frames! : Thanks for any info. : -Jim : . . . . : James Gourgoutis[http://www.pitt.edu/~skoop](412.683.7654) -- _____________________________________________________________ Gregory S. Lewis | Phone: (512) 471-3105 Center for Nonlinear Dynamics | FAX: (512) 471-1558 University of Texas at Austin | e-mail: Austin, TX 78712 USA | lewis@chaos.ph.utexas.edu | ____________________________________________________________ Article 75443 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!newsfeed.internetmci.com!hsno.wco.com!news.wco.com!not-for-mail From: lapdog@wco.com (Gary Helfrich) Newsgroups: rec.bicycles.tech Subject: Re: need more help/info w/brazing Date: 15 Mar 1996 15:34:02 GMT Organization: WEST COAST ONLINE, Inc. Lines: 35 Message-ID: <4ic2la@news.wco.com> References: <4i9s0l@usenet.srv.cis.pitt.edu> NNTP-Posting-Host: shell.wco.com X-Newsreader: TIN [UNIX 1.3 950824BETA PL0] James W Gourgoutis (skoop+@pitt.edu) wrote: : While brazing, I try to avoid going this 'bright'/hot. The weird thing : is this: I'm using goggles with a grade 5 lens in them...they basically : make the world look dark green. I took them off before a joint had : completely cooled down, and though it looked normal/black through the : goggles, I was surprised to find that it was still quite red. So, I'm : thinking that the orange I'm seeing through the goggles is actually alot : hotter, and therefore my whole color perception is off, and I'm really : cooking my tubes! You might try to find OmniView replacement lenses for you goggles. (They are made by Gentex Optics, Inc., Carbondale, PA 18407) These lenses use a thin gold film rather than the "Sea Hunt" green which is more common. The gold lens has almost effect on the percieved color. I have only been able to get the lens in the 4"x5" flat plate version, but they are plastic, so you can just cut some round lenses for yourself. : What do other people wear/use/recommend while brazing? My torch's : instructions say to wear nothing lighter than a grade 5 lens. The AWS : handbook says "Goggles or Spectacles may be worn depending on the type of : brazing" (or something to that effect). Talbot, in the photos in his : book, is wearing ordinary eyeglasses with no gloves or anything. 5 is a bit dark. Brazing does not produce the huge UV output that arc welding does, so you can relax a bit about eye damage. I'd go with a 3 for general frame construction, but if you use a gas fluxer, you might want to use a 4. You need some protection from the glare of the flame. Wear gloves as well. Once you get used to them, you won't know that you have them on. You need your hands as much as your eyes to build a frame. Gary Helfrich Arctos Machine Article 75456 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!newsfeed.internetmci.com!howland.reston.ans.net!math.ohio-state.edu!magnus.acs.ohio-state.edu!lerc.nasa.gov!usenet.ins.cwru.edu!cleveland.Freenet.Edu!ed380 From: ed380@cleveland.Freenet.Edu (J. Lee) Newsgroups: rec.bicycles.tech Subject: Re: Framebuilding with silver or brass? Date: 15 Mar 1996 23:26:42 GMT Organization: Case Western Reserve University, Cleveland, OH (USA) Lines: 12 Message-ID: <4icubi@madeline.INS.CWRU.Edu> References: <4gcp8d@news.halcyon.com> <4h7kjs@news.doit.wisc.edu> <4hkc26@usenet.srv.cis.pitt.edu> Reply-To: ed380@cleveland.Freenet.Edu (J. Lee) NNTP-Posting-Host: piglet.ins.cwru.edu In a previous article, skoop+@pitt.edu (James W Gourgoutis) says: >The rod I ended up using for this joint was Bernz-o-matic NS-3 or >something like that. It's supposedly a Nickel-Silver alloy, and is flux >coated (blue in color). I always thought that 'nickel-silver' contained NO silver in the alloy. I'm sure there's a bunch of welders out there who know the real answer. Article 20250 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!uunet!in2.uu.net!newsfeed.internetmci.com!howland.reston.ans.net!vixen.cso.uiuc.edu!uwm.edu!msunews!netnews.upenn.edu!Lehigh.EDU!Lehigh.EDU!not-for-mail From: jdc6@Lehigh.EDU Newsgroups: rec.crafts.metalworking Subject: Re: What filler rod to use for fillet brazing? Date: 25 Nov 1995 11:27:39 -0500 Lines: 29 Message-ID: <497g5r$1r0o@ns5-1.CC.Lehigh.EDU> NNTP-Posting-Host: ns5-1.cc.lehigh.edu In article <48vifp$1eb@usenet.srv.cis.pitt.edu>, skoop+@pitt.edu (James W Gourgo utis) writes: >I want to do some fillet brazing on a bike frame in the near future. >What kind/type of filler rod should I use? If someone could give me % >composition of the components, that'd be great...or any other info. >I've spent the past month researching different types of silver wire, >only to find that I need to use brass wire for fillets. (I thought that I >just needed silver wire with a low silver content, but was recently told >that this is incorrect.) > >Please respond via email. > >Thanks! >-Jim >. . . . >James Gourgoutis [http://www.pitt.edu/~skoop](412.683.7654) > Jim, look for some Eutectic 16 or Allstate 11, If you want a flux coated rod it will be 16FC or 11FC. I've used them both with good results for formula car frame repair. Good Luck, John ******************************************************************************* * John Caffrey * Protoform Formula Vee * * Engineering Technician * Rotus/Ford Super Seven * * Dept. of Chemical Engineering * * * Lehigh University, Bethlehem, PA * * ******************************************************************************* Article 23319 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!gatech!usenet.eel.ufl.edu!newsfeed.internetmci.com!howland.reston.ans.net!nntp.crl.com!pacbell.com!amdahl.com!netcomsv!uu4news.netcom.com!flying!frisbie From: frisbie@flying-disk.com (Alan Frisbie) Newsgroups: rec.crafts.metalworking Subject: Re: Welding with propane? Message-ID: <1996Feb1.093124.769@flying-disk.com> Date: 1 Feb 96 09:31:23 PST References: <4elu32@nonews.col.hp.com> <4em1mr$699@mozo.cc.purdue.edu> <4eotmk@bmerhc5e.bnr.ca> Organization: Flying Disk Systems, Inc. Lines: 75 In article <4eotmk@bmerhc5e.bnr.ca>, cclau@bmers2dd.bnr.ca (Christopher Lau) writes: > : You can use propane-air for silver brazing brass if the piece is small > : enough. That works, but I prefer to use MAPP gas and air for that. > ^^^^ > This has been bugging me for ages.. what the @#$^%! does MAPP mean anyways? MAPP is a registered trademark for the stabilized liquefied mixture of methylacetylene (CH3:C:CH) and propadiene (CH2:C:CH2) gases. It is one of approximately 26 methylacetylene-propadiene (MPS) gases marketed. I am not an expert in any area of welding, but I do have a textbook. To quote from "Welding Principles and Applications": "Oxy MAPP combusts with a high-heat, high-temperature flame what works well for cuting, heating, brazing, and metallizing. The gases mixed to produce MAPP both have the same atomic composition. This means that three carbon and four hydrogen atoms are present in each molecule of gas. Molecules of each gas therefore have the same mass and size, even though they are shaped differently. Because they are the same mass and size, the gas molecules form a stable mixture that remains uniformly mixed in the cylinder. This stabilization of mixture assures a uniform and consistent flame for easier quality control. Oxy MAPP produces a neutral flame temperature of 5,301 degrees F (2,927 C) that yields a heat value of 517 Btu/cubic foot in the primary flame (vs 507 for acetylene) and 1,889 Btu/cubic foot in the secondary flame (vs 963 for acetylene). The total heat value is 2,406 Btu/cubic foot (1470 for acetylene). The difference between the temperature produced by a neutral oxyacetylene flame and a neutral oxy MAPP flame is only 288 degrees F. Both flames are well above the approximately 2,800 degrees F temperature required to melt mild steel. Although MAPP is not normally recommended for use in gas welding, it can be used sucessfully. because the secondary flame of MAPP produces almost twice the heat of the acetylene flame, distortion is more of a problem with MAPP than with actylene. Also, it is more difficult to melt the root of the joint using MAPP. Because of the higher heat, the sides of a T-joint melt first. This is not as much of a problem with other joint designs. All gases used as alternatives to acetylene are safer to use, store, and handle. MAPP has each one of the safety features of the other fuel gases. These safety features include shock stability, narrow explosive limits in air, no pressure limitation, and slow burning velocities. Another safety advantage of MAPP is its smell. The odor of MAPP can be detected when there is as little as 100 parts per million of the gas of 1/340 of its lower explosive limit in air. By law, propane, natural gass, and propylene must have an odor added to them so that they can be detected at a concentration of 1/15 of their lower explosive limit in air. The ability to detect even small leaks can save gas and avoide the possibility of explostions. The foul odor of MAPP allows leaks to be found more than twenty-two times faster than acetylene leaks can be found." I know this more than you asked, but one I started typing, I couldn't stop. :-) > I've been using propylene (+oxygen) in my torch, is this the > same as MAPP?? No, but its heat and temperature characteristics are similar. The book doesn't give any more details on propylene. -- Alan E. Frisbie Frisbie@Flying-Disk.Com -- Flying Disk Systems, Inc. -- 4759 Round Top Drive (213) 256-2575 (voice) -- Los Angeles, CA 90065 (213) 258-3585 (FAX) Article 23633 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!gatech!newsfeed.internetmci.com!vixen.cso.uiuc.edu!saluki-news.wham.siu.edu!reliant!john From: "John R. Johnson" Newsgroups: rec.crafts.metalworking Subject: Re: Welding with propane? Date: Wed, 7 Feb 1996 11:50:57 -0600 Organization: Southern Illinois University - Carbondale Lines: 35 Message-ID: References: <4elu32@nonews.col.hp.com> <4eoplo@meaddata.lexis-nexis.com> <3110bd24.324080505@news.demon.co.uk> <4faf2j@usenet.srv.cis.pitt.edu> NNTP-Posting-Host: reliant.c-cwis.siu.edu Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Sender: john@reliant In-Reply-To: <4faf2j@usenet.srv.cis.pitt.edu> An oxidizing flame has excess oxygen. The excess oxygen will combine with the metal you are heating. We call it corrosion. A nuetral flame has exactly the right mixture of gasses so that they are both consumed completely. There is neither excess oxygen or excess acetylene. A reducing flame has excess acetylene. This can pull oxygen from the hot metal to combine with the acetylene. It can literally "unrust" the hot metal. I usually leave a slight feather ( reducing ) on my flame when I am welding something rusty. John On 7 Feb 1996, James W Gourgoutis wrote: > In article <3110bd24.324080505@news.demon.co.uk>, > Andy Dingley wrote: > > >really oxidisng flame and so you're burning your way through the steel > > > This is most likely a really basic question, but can somebody describe > the differences between an oxidizing, neutral, and reducing flame? I've > seen the terms alot recently, but haven't found any definitions. > > Thanks, > -Jim > . . . . > James Gourgoutis [http://www.pitt.edu/~skoop](412.683.7654) > > > > Article 23651 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!gatech!news.radio.org!news From: ke4zv@radio.org Newsgroups: rec.crafts.metalworking Subject: Re: Welding with propane? Date: Wed, 07 Feb 96 14:58:35 PDT Organization: TAC, The Atlanta Connection and Radio.Org Lines: 40 Message-ID: References: <4elu32@nonews.col.hp.com> <4eoplo@meaddata.lexis-nexis.com> <3110bd24.324080505@news.demon.co.uk> <4faf2j@usenet.srv.cis.pitt.edu> NNTP-Posting-Host: ke4zv.radio.org Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII X-Newsreader: NEWTNews & Chameleon -- TCP/IP for MS Windows from NetManage In Article<4faf2j@usenet.srv.cis.pitt.edu>, writes: > This is most likely a really basic question, but can somebody describe > the differences between an oxidizing, neutral, and reducing flame? I've > seen the terms alot recently, but haven't found any definitions. Ok, it's really simple. An oxidizing flame has an excess of oxygen, a reducing flame has a shortage of oxygen, and a neutral flame has a perfect amount of oxygen to be totally consumed by the supplied fuel. Since an oxidizing flame has an excess of *really* hot oxygen available, it will *oxidize* materials in the flame, such as your hunk of iron. When oxidation occurs slowly on iron, we call it rust, when it occurs rapidly, we call it burning. A cutting flame has a strong excess of oxygen that literally burns the iron in its path. A reducing flame has a dearth of oxygen in it. It has hot fuel hungry for oxygen present and this fuel can *draw* oxygen out of materials being heated by the flame. It is thus said to "reduce" the material. With torch flames, the excess fuel is usually carbon, and some of this carbon can combine with iron to form a hard *case* on the surface of the material. This is how flame hardening is done. A neutral flame is used for general heating, welding, soldering, or brazing. It is the hottest flame that doesn't consume the material it is heating. It's hard to describe how to adjust a torch to achieve each of these types of flames, but it is very easy to demonstrate. The look and *sound* of each of these flame types is very distinctive. Reducing flames are "soft" with a large feathery outer cone surrounding a smaller central cone. Oxidizing flames are harsh sounding with sharp cones that stand off from the torch. A neutral flame has a single well defined cone of flame. It is adjusted from a reducing flame by just adding enough oxygen to merge the outer feathery cone with the small central cone of the flame. This is the type of flame you'll use most often. Gary Article 70673 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!swrinde!howland.reston.ans.net!news-e1a.megaweb.com!newstf01.news.aol.com!newsbf02.news.aol.com!not-for-mail From: bobaxe@aol.com (Bobaxe) Newsgroups: rec.bicycles.tech Subject: Low temp fillet brazing Date: 25 Jan 1996 11:41:17 -0500 Organization: America Online, Inc. (1-800-827-6364) Lines: 12 Sender: root@newsbf02.news.aol.com Message-ID: <4e8brd@newsbf02.news.aol.com> Reply-To: bobaxe@aol.com (Bobaxe) NNTP-Posting-Host: newsbf02.mail.aol.com Can anyone comment on alternatives to the high temp standard low fuming bronze alloys. These typically have a liquidus around 1700 degrees. I've been told that a moderate silver content (25%) alloy can be used for fillet brazing while providing the benefit of a liquidus around 1250 degrees and a reasonably wide plastic range. While I don't doubt such an alloy exists and that one could build at least a small fillet using it, I don't know how to evaluate the strength of the resulting joint. Is the reduced heating of the tube a virtue with no drawbacks. If so. why do all the pros use bronze (surely the braze alloy cost is small compared to the other ingredients in a $1000+ frame)? Thanks for any guidance. Sincerely, Bob Article 70800 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!newsfeed.internetmci.com!in1.uu.net!zib-berlin.de!fub!quijote.in-berlin.de!hajo Date: 26 Jan 1996 00:00:00 +0000 From: hajo@quijote.in-berlin.de (Hans-Joachim Zierke) Newsgroups: rec.bicycles.tech Message-ID: <61be1gmKYgB@quijote.in-berlin.de> References: <4e8brd@newsbf02.news.aol.com> Subject: Re: Low temp fillet brazing X-Newsreader: CrossPoint v3.1 R/C211 Organization: =?ISO-8859-1?Q?B=FCro_f=FCr_ungew=F6hnliche_Ma=DFnahmen?= Lines: 35 Bobaxe writes: > Can anyone comment on alternatives to the high temp standard low fuming > bronze alloys. These typically have a liquidus around 1700 degrees. I've > been told that a moderate silver content (25%) alloy can be used for > fillet brazing while providing the benefit of a liquidus around 1250 > degrees and a reasonably wide plastic range. It is possible to braze it at 610 degrees with 40% silver, and at 650 degrees with 56% silver cadmium-free. Both setups need so tight a tolerance in tube metering, that you might not want to pay for it. It might get economical with high-precision laser cutting equipment getting cheaper. > If so. why do all > the pros use bronze (surely the braze alloy cost is small compared to the > other ingredients in a $1000+ frame)? Thanks for any guidance. All the pros use either 40% or 56% silver in _lugged_ frames, at least those pros whos frames I might buy. In lugless construction, many builders use high strength alloys with some nickel content. The damage to the tube is a function of heat and time. Since lugless needs much less time to heat up for brazing, this can be a good compromise of strength versus costs. hajo -- T . E . L . E . K . O . M We specialize in cross subsidization Private Customer Shafting Government Staff Grafting Article 70766 of rec.bicycles.tech: Newsgroups: rec.bicycles.tech Path: newsfeed.pitt.edu!gatech!newsfeed.internetmci.com!news.kei.com!ub!freenet.buffalo.edu!bd427 From: bd427@freenet.buffalo.edu (Doug Milliken) Subject: Re: Low temp fillet brazing Message-ID: Sender: nntp@acsu.buffalo.edu Nntp-Posting-Host: freenet.buffalo.edu Reply-To: bd427@freenet.buffalo.edu (Doug Milliken) Organization: State University of New York At Buffalo, NY (USA) References: <4e8brd@newsbf02.news.aol.com> Date: Fri, 26 Jan 1996 06:30:49 GMT Lines: 23 In a previous article, bobaxe@aol.com (Bobaxe) says: >Can anyone comment on alternatives to the high temp standard low fuming >bronze alloys. These typically have a liquidus around 1700 degrees. I've >been told that a moderate silver content (25%) alloy can be used for >fillet brazing while providing the benefit of a liquidus around 1250 >degrees and a reasonably wide plastic range. While I don't doubt such an >alloy exists and that one could build at least a small fillet using it, I >don't know how to evaluate the strength of the resulting joint. Is the >reduced heating of the tube a virtue with no drawbacks. If so. why do all >the pros use bronze (surely the braze alloy cost is small compared to the >other ingredients in a $1000+ frame)? Thanks for any guidance. I know at least one bike mfr that uses a brazing alloy that is about one-half silver -- to fillet-braze stainless steel. I believe that this alloy was chosen for its color match to the stainless as much as for the low temperature. Results are good, but the one guy in the shop that can do it is pretty d*** good at his craft. I tried and didn't get anything like a good looking fillet -- even though I'm pretty good with a normal brass rod. -- Article 70796 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!newsfeed.internetmci.com!in2.uu.net!tsunami.ixa.net!news.aa.net!ratty.wolfe.net!josh From: josh@WOLFENET.COM (Joshua_Putnam) Newsgroups: rec.bicycles.tech Subject: Re: Low temp fillet brazing Date: 26 Jan 1996 18:17:16 GMT Organization: Wolfe Internet Access, L.L.C. Lines: 19 Message-ID: <4eb5rc@news1.wolfe.net> References: <4e8brd@newsbf02.news.aol.com> Reply-To: Josh@WolfeNET.com NNTP-Posting-Host: gonzo.wolfenet.com In bd427@freenet.buffalo.edu (Doug Milliken) writes: >I know at least one bike mfr that uses a brazing alloy that is about >one-half silver -- to fillet-braze stainless steel. I believe that this >alloy was chosen for its color match to the stainless as much as for the >low temperature. Silver brazing is usually recommended for stainless steel. Brass can cause cracking, but I don't remember why. Henry James Bicycles recommends brazing their dropouts with silver solder with gap filling capability, and supplies BAg24 (50% Ag, 2% Ni) filler with them. I don't fillet braze, so I don't know if this would work for that. -- Josh@WolfeNet.com is Joshua Putnam / P.O. Box 13220 / Burton, WA 98013 "My other bike is a car." New & used bike parts for sale: finger Joshua_Putnam@WolfeNet.com for list. Suntour PowerFlo 7-sp freewheel, 13x28, new, $26 + postage Article 70834 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!newsfeed.internetmci.com!in2.uu.net!newstf01.news.aol.com!newsbf02.news.aol.com!not-for-mail From: bikenbear@aol.com (BikeNbear) Newsgroups: rec.bicycles.tech Subject: Re: Low temp fillet brazing Date: 26 Jan 1996 21:52:33 -0500 Organization: America Online, Inc. (1-800-827-6364) Lines: 12 Sender: root@newsbf02.news.aol.com Message-ID: <4ec41h@newsbf02.news.aol.com> References: <4eb5rc@news1.wolfe.net> Reply-To: bikenbear@aol.com (BikeNbear) NNTP-Posting-Host: newsbf02.mail.aol.com Use the bronze rod that Henry James sells. The Gasflux Company did some development work on it and rumor has it that Trek also had a hand in developing the alloy along with Mike Melton who did some work on some Olympic bikes. This is proven stuff for fillet brazed frames and is the only rod I use and I personally fillet brazed about 500 Tesch frames and Dave Tesch probably brazed another 200 frames with the same type of rod. If you have cracking problems 2 inches from the head tube- down tube joint, its not as a result of fillet brazing. We never had any problems with cracking. The old Fisher mountain bike team frames were all fillet brazed back in the days when Joe Murray was racing and they never had frame failures that could be in any way be associated with fillet brazing. Leo Castellon Article 70852 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!newsfeed.internetmci.com!howland.reston.ans.net!usc!news.cerf.net!news From: Racesales@Bushido.com (WJT) Newsgroups: rec.bicycles.tech Subject: Re: Low temp fillet brazing Date: 27 Jan 1996 07:31:46 GMT Organization: Bushido Racing Lines: 11 Message-ID: <4eckd2$8h2@news.cerf.net> References: <4eb5rc@news1.wolfe.net> <4ec41j@newsbf02.news.aol.com> NNTP-Posting-Host: a2p7r.lainet.com Mime-Version: 1.0 Content-Type: Text/Plain; charset=US-ASCII >If you have cracking problems 2 inches from the head tube- down tube >joint, its not as a result of fillet brazing. We never had any problems >with cracking. The old Fisher mountain bike team frames were all fillet >brazed back in the days when Joe Murray was racing and they never had >frame failures that could be in any way be associated with fillet brazing. Leo, We sent back at least 6 brazed frames for that very reason. They were eventually warrantied. Localized fatigue from the heat band. Very common in aluminum construction too. -Bill Article 70755 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!swrinde!howland.reston.ans.net!usc!news.cerf.net!news From: Racesales@Bushido.com (WJT) Newsgroups: rec.bicycles.tech Subject: Re: Low temp fillet brazing Date: 26 Jan 1996 12:42:51 GMT Organization: Bushido Racing Lines: 18 Message-ID: <4eai8b$7q8@news.cerf.net> References: <4e8brd@newsbf02.news.aol.com> NNTP-Posting-Host: a1p2r.lainet.com Mime-Version: 1.0 Content-Type: Text/Plain; charset=US-ASCII >Can anyone comment on alternatives to the high temp standard low fuming >bronze alloys. These typically have a liquidus around 1700 degrees. >don't know how to evaluate the strength of the resulting joint. Is the >reduced heating of the tube a virtue with no drawbacks. Bob, Fillet brazed frames are pretty. But it kills the tubing. Examine the warranty those pros offer. Low temp brass is still heated to 1500+F and chrome-moly really, really likes to stay under 1100F to retain it's normalized strength. Silver soldered lugged frames are easy to weld at 900F and the tubes love it. Reynolds tubing, other than 753+, like the higher heats that brazing requires, but not over large areas. If you must fillet (without a bondo joint under the paint), expect about a years lifespan under fairly harsh conditions. The tubing will crack on the downtube 2" from the headtube, and at either end of the seat tube within 1" of the welds. If you use a JetFluxer with high silver content filler you can keep the heat to 1000F or so. The frame will be pretty, but the joints will have zero strength. Art has it drawbacks. -Bill Article 71025 of rec.bicycles.tech: Path: newsfeed.pitt.edu!skoop From: skoop+@pitt.edu (James W Gourgoutis) Newsgroups: rec.bicycles.tech Subject: Re: Low temp fillet brazing Date: 29 Jan 1996 17:26:24 GMT Organization: University of Pittsburgh Lines: 16 Sender: skoop+@pitt.edu Message-ID: <4ej000$3r8@usenet.srv.cis.pitt.edu> References: <4eb5rc@news1.wolfe.net> <4ec41j@newsbf02.news.aol.com> NNTP-Posting-Host: unixs2.cis.pitt.edu In article <4ec41j@newsbf02.news.aol.com>, BikeNbear wrote: >Use the bronze rod that Henry James sells. The Gasflux Company did some Does anyone know the AWS designation for this type of rod? Or for the aforementioned "low fuming bronze rod", for that matter? p.s. glad to see this thread--it's answering some questions I've had for a long time. Thanks. -Jim . . . . James Gourgoutis [http://www.pitt.edu/~skoop](412.683.7654) Article 71157 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!newsfeed.internetmci.com!in1.uu.net!zib-berlin.de!fub!quijote.in-berlin.de!hajo Date: 30 Jan 1996 00:00:00 +0000 From: hajo@quijote.in-berlin.de (Hans-Joachim Zierke) Newsgroups: rec.bicycles.tech Message-ID: <61sBJMj@quijote.in-berlin.de> References: <4e8brd@newsbf02.news.aol.com> <4eai8b$7q8@news.cerf.net> Subject: Re: Low temp fillet brazing X-Newsreader: CrossPoint v3.1 R/C211 Organization: =?ISO-8859-1?Q?B=FCro_f=FCr_ungew=F6hnliche_Ma=DFnahmen?= Lines: 26 WJT writes: > Fillet brazed frames are pretty. But it kills the tubing. Examine > the wa those > pros offer. Low temp brass is still heated to 1500+F and chrome-moly really, > really likes to stay > under 1100F to retain it's normalized strength. Silver soldered lugged frames > are easy to weld > at 900F and the tubes love it. Reynolds tubing, other than 753+, like the > higher heats that > brazing requires, but not over large areas. As soon as you look at strength graphs after brass brazing, you'll see that Reynolds 531 does not "love" it. Even with hand-held silver brazing, you'll see the heated area on the graph, though it is very near to invisible. hajo -- T . E . L . E . K . O . M We specialize in cross subsidization Private Customer Shafting Government Staff Grafting Article 17022 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!skoop From: skoop+@pitt.edu (James W Gourgoutis) Newsgroups: rec.crafts.metalworking Subject: MIG vs. brazing for bike frames Date: 6 Sep 1995 14:30:21 GMT Organization: University of Pittsburgh Lines: 48 Sender: skoop+@pitt.edu Message-ID: <42kb9t@usenet.srv.cis.pitt.edu> NNTP-Posting-Host: unixs3.cis.pitt.edu Summary: which should I use? This is my first post to this group after lurking for a couple of weeks, so please forgive me in advance if I break any netiquette rules. Myself and 2 friends want to build/modify bicycle frames. We do not know much about welding and/or brazing, and would like to buy some basic equipment and a book or two and learn by doing. We have been researching what type of equipment (TIG, MIG, or OA brazing) to buy for the past month, but have received differing opinions, which is why I'm asking here. For those who may not know, steel bicycle frames are generally fabricated by 3 different methods: TIG welding, lugged OA brazing, or lugless OA fillet brazing. We have only a small budget (~$500). Our initial plan was to purchase a small portable 110V MIG welder (as has been discussed several times here), but several people I have talked to via email (from other newsgroups) have indicated that MIG welding will not work well on the thin wall chromoly and mild steel tubes used in bike frames (0.9 mm, for example). For this reason we have also begun considering getting an OA brazing rig instead. I have also been given the impression that small, portable TIG units are WAY out of our budget ($4500 ?) and are hard to learn--is this true? We don't really need/want something that will give us professional results. We just want to be weekend bike hackers/framebuilders for fun and experience. I've checked the FAQ, but these questions still remain: Which should we choose: MIG or OA brazing (assuming that TIG is out of our league)? *Is* TIG out of our price range/knowledge level? Is fillet brazing easier to learn than MIG welding? Will MIG welding produce mechanically sound welds on thinwall steel tubing? Do cheap portable TIG units exist? Is this a ludicrous idea? Any other advice will be extremely appreciated! Thanks, Jim . . . . James Gourgoutis [http://www.pitt.edu/~skoop] Article 17031 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!dsinc!spool.mu.edu!howland.reston.ans.net!newsfeed.internetmci.com!news.sprintlink.net!neon.house.gov!news From: hcs@hsan.loc.gov Newsgroups: rec.crafts.metalworking Subject: Re: MIG vs. brazing for bike frames Date: 6 Sep 1995 19:12:46 GMT Organization: Library of Congress Lines: 23 Message-ID: <42krre@neon.house.gov> References: <42kb9t@usenet.srv.cis.pitt.edu> Reply-To: hcs@hsan.loc.gov NNTP-Posting-Host: 140.147.60.23 X-Newsreader: IBM NewsReader/2 v1.00 In <42kb9t@usenet.srv.cis.pitt.edu>, skoop+@pitt.edu (James W Gourgoutis) writes: >I have also been given the impression that small, >portable TIG units are WAY out of our budget ($4500 ?) and are hard to >learn--is this true? Miller makes a small TIG welder--I think it's called the Econo-TIG--that sells for around $1200. It would almost certainly do what you want. I personally found TIG welding to be *very* easy--FAR easier than I found MIG, which is usually touted as being the simplest. (I also found oxyacetylene easy, easier than stick or MIG). YMMV. I suggest going to a welding supply shop in your area and explaining what you want to do. They will know how to advise you. You could also consult the American Welding Society. These opinions are my own, not those of the Library of Congress. Howard Sanner hcs@hsan.loc.gov sanner@mail.loc.gov Article 17037 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!skoop From: skoop+@pitt.edu (James W Gourgoutis) Newsgroups: rec.crafts.metalworking Subject: Re: MIG vs. brazing for bike frames Date: 6 Sep 1995 20:52:35 GMT Organization: University of Pittsburgh Lines: 12 Sender: skoop+@pitt.edu Message-ID: <42l1mj@usenet.srv.cis.pitt.edu> References: <42kb9t@usenet.srv.cis.pitt.edu> NNTP-Posting-Host: unixs5.cis.pitt.edu It's just me following up my own post. I forgot to ask... Also, what about regular stick-arc welding for bike frames? Totally out of the question? MANY thanks to everyone who's responded already! Jim . . . . James Gourgoutis [http://www.pitt.edu/~skoop] Article 17044 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!uunet!in1.uu.net!tank.news.pipex.net!pipex!swrinde!elroy.jpl.nasa.gov!lll-winken.llnl.gov!fnnews.fnal.gov!nntp-server.caltech.edu!schedir.krl.caltech.edu!shoppa From: shoppa@schedir.krl.caltech.edu (Tim Shoppa) Newsgroups: rec.crafts.metalworking Subject: Re: MIG vs. brazing for bike frames Date: 6 Sep 1995 22:28:19 GMT Organization: Kellogg Radiation Lab, Caltech Lines: 61 Message-ID: <42l7a3$266@gap.cco.caltech.edu> References: <42kb9t@usenet.srv.cis.pitt.edu> NNTP-Posting-Host: schedir.krl.caltech.edu In article <42kb9t@usenet.srv.cis.pitt.edu>, James W Gourgoutis wrote: >This is my first post to this group after lurking for a couple of weeks, >so please forgive me in advance if I break any netiquette rules. > >Myself and 2 friends want to build/modify bicycle frames. We do not know >much about welding and/or brazing, and would like to buy some basic >equipment and a book or two and learn by doing. We have been >researching what type of equipment (TIG, MIG, or OA brazing) to buy for >the past month, but have received differing opinions, which is why I'm >asking here. > >We have only a small budget (~$500). Our initial plan was to purchase a >small portable 110V MIG welder (as has been discussed several times here), >but several people I have talked to via email (from other newsgroups) have >indicated that MIG welding will not work well on the thin wall chromoly and >mild steel tubes used in bike frames (0.9 mm, for >example). For this reason we have also begun considering getting an OA >brazing rig instead. I have also been given the impression that small, >portable TIG units are WAY out of our budget ($4500 ?) and are hard to >learn--is this true? > >We don't really need/want something that will give us professional results. >We just want to be weekend bike hackers/framebuilders for fun and experience. > >I've checked the FAQ, but these questions still remain: > >Which should we choose: MIG or OA brazing (assuming that TIG is out of >our league)? I would say brazing. MIG is useful to know, but not nearly as forgiving for beginners as oxyacetylene brazing. I would venture to say that brazing is almost foolproof (meaning even I could do a decent job after just a few practice joints). I've even seen some Oxyacetylene sets that allow you to use little "midget" cylinders that are refillable; for work like you'll be doing such a setup would be ideal. >Is fillet brazing easier to learn than MIG welding? I would say so. And an Oxyacetylene torch is a useful tool for more than just welding, you know. >Is this a ludicrous idea? No, not at all. I've never built a frame from scratch, but I have succesfully brazed frames back together after the original welds failed. None of my repairs have broken yet! If you're going to be building frames from scratch, I imagine you'd also want to spend some money on some good material for forming the tubing. Actually making the joint is usually rather easy; getting your materials to nicely meet each other is the hard part. (This is from my experience with totally replacing the exhaust system of a '73 Pontiac LeMans; having the right tools to work with the tubing can turn a dirty job that takes two days and leaves every joint in your body sore into a quick job that is very neatly done.) Tim. (shoppa@altair.krl.caltech.edu) Article 17050 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!dsinc!spool.mu.edu!howland.reston.ans.net!vixen.cso.uiuc.edu!vmd.cso.uiuc.edu!EPLUS17 From: EPLUS17@vmd.cso.uiuc.edu (Richard Engelbrecht-Wiggans) Newsgroups: rec.crafts.metalworking Subject: Re: MIG vs. brazing for bike frames Date: Wed, 06 Sep 95 20:20:36 CDT Organization: C.C.S.O. Lines: 33 Message-ID: <1741111E1B.EPLUS17@vmd.cso.uiuc.edu> References: <42kb9t@usenet.srv.cis.pitt.edu> <42l7a3$266@gap.cco.caltech.edu> NNTP-Posting-Host: vmd.cso.uiuc.edu In article <42l7a3$266@gap.cco.caltech.edu> shoppa@schedir.krl.caltech.edu (Tim Shoppa) writes: > >I would say brazing. MIG is useful to know, but not nearly as >forgiving for beginners as oxyacetylene brazing. I would venture >to say that brazing is almost foolproof (meaning even I could >do a decent job after just a few practice joints). > My sentiments exactly. I picked up brazing easily, and have used it extensively (including making a tandem bike frame and a "kiddie" crank adapter so that my daughter can ride on our triplet.) A few years ago, I got a welder and a TIG attchment; it cost about $600 total, works great on stainless tubing, but is only DC and thus won't do aluminum. The problem with TIG (or MIG, and ESPECIALLY stick) welding of thin material is how easily you can burn through it and leave a big gaping hole; brazing is done at a temperture below the melting point of the materials you are joining and thus you don't have the same problem. Also, if you want a really pretty joint, a brass fillet--in my experience--is smoother than anything I've seen with welding (and if its not perfect, brass files/sands very nicely. >I've even seen >some Oxyacetylene sets that allow you to use little "midget" cylinders >that are refillable; for work like you'll be doing such a setup >would be ideal. > I've done all my brazing with a 20 year old Sears Oxy/Mapp gas setup; the Oxy bottle is refillable, and the Mapp cylinders are disposable. A bicycle frame takes less than one of each. Article 17053 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!uunet!in1.uu.net!newstf01.news.aol.com!newsbf02.news.aol.com!not-for-mail From: ernieleim@aol.com (ErnieLeim) Newsgroups: rec.crafts.metalworking Subject: Re: MIG vs. brazing for bike frames Date: 6 Sep 1995 22:18:03 -0400 Organization: America Online, Inc. (1-800-827-6364) Lines: 31 Sender: root@newsbf02.news.aol.com Message-ID: <42lkor@newsbf02.news.aol.com> References: <42kb9t@usenet.srv.cis.pitt.edu> Reply-To: ernieleim@aol.com (ErnieLeim) NNTP-Posting-Host: newsbf02.mail.aol.com Brazing, Mig, or tig, for bike frames ? I own all three of the options you list ( yes stick is out of the question). Oxy-acet. is the best low-cost option. I would be leery of trying to use a baby mig to weld bike tubes since it is very easy to over heat the weld and burn through on such thin materiel. Tig is an option if you have about $1500 to spend on a Miller Econotig. They are great machines for small projects such as bike frames. I've had mine for a year and a half and wouldn't give it up for anything( well maybe a Cybertig) . Over all I feel you should either get to know someone who can let you play with the equipment before you buy it , or best of all enroll in welding classes at your local community college. Taking actual classes can also give you a much better idea of how welding works, which type of welding to use when , and what is good equipment. Good luck on your bike frames. @---------------------------------------------------------@ Ernie Leimkuhler Stagesmith Productions Custom Metal Fabrication * ABANA SCA AWS USITT IATSE local 15, 488 * Renton, WA *"For this was a time when men were REAL men, women were REAL women and small furry creatures from alpha centauri were REAL small furry creatures from alpha centauri." --- Douglas Adams * @---------------------------------------------------------@ Article 17078 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!dsinc!spool.mu.edu!howland.reston.ans.net!tank.news.pipex.net!pipex!in2.uu.net!nwlink.com!port3 From: hr@nwlink.com (Rich S) Newsgroups: rec.crafts.metalworking Subject: Re: MIG vs. brazing for bike frames Date: 7 Sep 1995 17:46:36 GMT Organization: Northwest Link Lines: 11 Message-ID: <42nb5t@alaska.nwlink.com> References: <42kb9t@usenet.srv.cis.pitt.edu> <42l1mj@usenet.srv.cis.pitt.edu> NNTP-Posting-Host: port3.annex.nwlink.com X-Newsreader: News Xpress Version 1.0 Beta #3 You could take the ultra-cheap TIG route (like I did). If you have or can get a arc welding set that is DC capable you can add a TIG torch, tungsten electrodes, regulators and usundrie for around $250 extra. It dosen't have a high frequency unit so you can't weld aluminum and striking an arc is a pain--you have to use a carbon or copper plate to avoid contaminating the electrode. The HPBook Welder's Handbook by Richard Finch and Tom Monroe is pretty informative and discribes the above mentioned setup. Sincerly; Rich S Article 17053 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!uunet!in1.uu.net!newstf01.news.aol.com!newsbf02.news.aol.com!not-for-mail From: ernieleim@aol.com (ErnieLeim) Newsgroups: rec.crafts.metalworking Subject: Re: MIG vs. brazing for bike frames Date: 6 Sep 1995 22:18:03 -0400 Organization: America Online, Inc. (1-800-827-6364) Lines: 31 Sender: root@newsbf02.news.aol.com Message-ID: <42lkor@newsbf02.news.aol.com> References: <42kb9t@usenet.srv.cis.pitt.edu> Reply-To: ernieleim@aol.com (ErnieLeim) NNTP-Posting-Host: newsbf02.mail.aol.com Brazing, Mig, or tig, for bike frames ? I own all three of the options you list ( yes stick is out of the question). Oxy-acet. is the best low-cost option. I would be leery of trying to use a baby mig to weld bike tubes since it is very easy to over heat the weld and burn through on such thin materiel. Tig is an option if you have about $1500 to spend on a Miller Econotig. They are great machines for small projects such as bike frames. I've had mine for a year and a half and wouldn't give it up for anything( well maybe a Cybertig) . Over all I feel you should either get to know someone who can let you play with the equipment before you buy it , or best of all enroll in welding classes at your local community college. Taking actual classes can also give you a much better idea of how welding works, which type of welding to use when , and what is good equipment. Good luck on your bike frames. @---------------------------------------------------------@ Ernie Leimkuhler Stagesmith Productions Custom Metal Fabrication * ABANA SCA AWS USITT IATSE local 15, 488 * Renton, WA *"For this was a time when men were REAL men, women were REAL women and small furry creatures from alpha centauri were REAL small furry creatures from alpha centauri." --- Douglas Adams * @---------------------------------------------------------@ Article 17097 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!uunet!in1.uu.net!spool.mu.edu!howland.reston.ans.net!newsjunkie.ans.net!newstf01.news.aol.com!newsbf02.news.aol.com!not-for-mail From: glbwelding@aol.com (GLBWELDING) Newsgroups: rec.crafts.metalworking Subject: Re: MIG vs. brazing for bike frames Date: 7 Sep 1995 22:41:47 -0400 Organization: America Online, Inc. (1-800-827-6364) Lines: 4 Sender: root@newsbf02.news.aol.com Message-ID: <42oahb$450@newsbf02.news.aol.com> References: <42krre@neon.house.gov> Reply-To: glbwelding@aol.com (GLBWELDING) NNTP-Posting-Host: newsbf02.mail.aol.com My company deals in oxyacetylene welding equipment and deals with primarily people welding 4130 thin wall tubing call at 1-800-258-0126 for more info on this subject. Article 17091 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!uunet!in1.uu.net!spool.mu.edu!howland.reston.ans.net!nntp.crl.com!crl13.crl.com!not-for-mail From: kimberln@crl.com (J. Kimberlin) Newsgroups: rec.crafts.metalworking Subject: Re: MIG vs. brazing for bike frames Date: 7 Sep 1995 16:39:37 -0700 Organization: CRL Dialup Internet Access (415) 705-6060 [Login: guest] Lines: 29 Message-ID: <42nvrp@crl13.crl.com> References: <42kb9t@usenet.srv.cis.pitt.edu> <42l7a3$266@gap.cco.caltech.edu> <42n3n2@usenet.srv.cis.pitt.edu> NNTP-Posting-Host: crl13.crl.com In article <42n3n2@usenet.srv.cis.pitt.edu>, James W Gourgoutis wrote: > >Someone mentioned that you can get a brazing-torch set-up consisting of >JUST an acetylene tank, without an oxygen tank. This is attractive due >to the lower cost, etc. What are the relative merits/problems with each >(OA vs. just A)? You have a lot of advice and all good. Just to throw additional fodder in on the subject of heat and brazing, I have used ordinary house gas (methane) with air as preheat, ordinary house gas plus oxygen, propane with compressed air, and propane with oxygen. Generally, I like propane oxygen for a brazing flame with a propane-air burner heater for soaking heat. This is for brazing not silver soldering, just to get the terminology straight. Ordinary house gas and air is hot enough for general glass blowing (pyrex). Quartz takes a little more heat and we use oxygen and house gas for that. My personal prejudice says stay away from acetylene as it is costly and makes soot. The soot hangs in the cobwebs I never clean away in the shop and this eventually gets into my hair, etc. The idea really is to obtain the amount of heat you need to do the job, consistant with cost, time, and capability. JerryK Article 17083 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!uunet!in1.uu.net!news.compuserve.com!news.production.compuserve.com!news From: Dirc Evans <100666.1106@CompuServe.COM> Newsgroups: rec.crafts.metalworking Subject: Re: MIG vs. brazing for bike frames Date: 7 Sep 1995 19:28:09 GMT Organization: Metal Workx Lines: 25 Message-ID: <42nh49$1@mhafm.production.compuserve.com> References: <42l7a3$266@gap.cco.caltech.edu> The case for different methods of repair/ building bike frames is very much dependent on the frame material. Briefly, the superlight steel frames are made from precise heat treated alloys. Welding has to unwanted effects: It adds extra weight with filler but the main reason is that welding takes the alloy beyond a certain temperature at which the alloy loses its strength and becomes extremely brittle. Other frame materials, such as Titanium and aluminium can be successfully TIG welded, but often require special heat treatments. There is however a recent development in a tubing that does not need the treatment. As for bonding and fibre matrix materials, adhesives are very specialised. That just leaves the High Tensile Steel tubing on common or garden bikes. You might as well MIG this stuff. To be honest, there is a hell of a lot to know about frame building and repair and I would hate to see anyone lose a load of money through lack of knowledge. Good luck! Article 17144 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!godot.cc.duq.edu!news.duke.edu!agate!newsxfer.itd.umich.edu!newsfeed.internetmci.com!howland.reston.ans.net!news.sprintlink.net!ratty.wolfe.net!josh From: josh@Wolfe.NET (Joshua_Putnam) Newsgroups: rec.crafts.metalworking Subject: Re: MIG vs. brazing for bike frames Date: 9 Sep 1995 20:54:47 GMT Organization: Wolfe Internet Access, L.L.C. Lines: 43 Message-ID: <42suuo@news1.wolfe.net> References: <42nh49$1@mhafm.production.compuserve.com> <1995Sep8.222936.4295@lmpsbbs.comm.mot.com> Reply-To: Josh@WolfeNET.com NNTP-Posting-Host: gonzo.wolfe.net In <1995Sep8.222936.4295@lmpsbbs.comm.mot.com> markl@ssd.comm.mot.com (Mark Lakomski) writes: >Brazing IMO will not work. The only brazing I've ever seen on a bicycle is on >a lugged frame where the lugging provides most of the strength. I would imagine >making lugs would be too complex of an operation for what you propose. Brazing >properly ( so as to obtain the advertised tensile rating of the material ) is >not as easy as you might think, especially on thin tubing. A brazed tubing butt >joint probably won't even support your own weight. You may be able to buy a set >of lugs for a frame at which point this might be a very attractive alternative. While lugs are the most common way of brazing a bike frame, they aren't required, and don't actually provide much of the strength of the joint. The main strength of the joint comes from properly mitering the intersecting tubes to get very close tolerances. Well-mitered joints will be close enough to allow silver brazing at full strength, but this takes a lot of work. Less expensive frames usually use brass brazing at looser tolerances. Lugless, fillet-brazed frames are lighter and nearly as strong as lugged frames, but much harder to build well both structurally and aesthetically. Structurally because the main function of lugs is to keep the tubes properly aligned while brazing, and aesthetically because it takes a lot of practice to make those beautifully smoothed fillets of brazing material around the joint without spattering excess material around. Still, if you want to spend the money you can buy a lugless brazed frame and not worry about premature failure because of the lack of lugs. A lot of old Schwinns were built this way and are still sound after many decades; current professional builders make lugless tandems and mountain bikes. You can even get custom-configured stems made of fillet brazed 4130 tubing, and it's hard to think of a joint on a bike that receives more stress than a stem quill. It's not unusual for most of the riders weight to land on one side of a handlebar giving 20cm of leverage against the stem, yet a simple mitered brazed joint is easily strong enough to handle it. (All this assumes competent brazing, of course.) -- Josh@WolfeNet.com is Joshua Putnam / P.O. Box 13220 / Burton, WA 98013 "My other bike is a car." Article 17053 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!uunet!in1.uu.net!newstf01.news.aol.com!newsbf02.news.aol.com!not-for-mail From: ernieleim@aol.com (ErnieLeim) Newsgroups: rec.crafts.metalworking Subject: Re: MIG vs. brazing for bike frames Date: 6 Sep 1995 22:18:03 -0400 Organization: America Online, Inc. (1-800-827-6364) Lines: 31 Sender: root@newsbf02.news.aol.com Message-ID: <42lkor@newsbf02.news.aol.com> References: <42kb9t@usenet.srv.cis.pitt.edu> Reply-To: ernieleim@aol.com (ErnieLeim) NNTP-Posting-Host: newsbf02.mail.aol.com Brazing, Mig, or tig, for bike frames ? I own all three of the options you list ( yes stick is out of the question). Oxy-acet. is the best low-cost option. I would be leery of trying to use a baby mig to weld bike tubes since it is very easy to over heat the weld and burn through on such thin materiel. Tig is an option if you have about $1500 to spend on a Miller Econotig. They are great machines for small projects such as bike frames. I've had mine for a year and a half and wouldn't give it up for anything( well maybe a Cybertig) . Over all I feel you should either get to know someone who can let you play with the equipment before you buy it , or best of all enroll in welding classes at your local community college. Taking actual classes can also give you a much better idea of how welding works, which type of welding to use when , and what is good equipment. Good luck on your bike frames. @---------------------------------------------------------@ Ernie Leimkuhler Stagesmith Productions Custom Metal Fabrication * ABANA SCA AWS USITT IATSE local 15, 488 * Renton, WA *"For this was a time when men were REAL men, women were REAL women and small furry creatures from alpha centauri were REAL small furry creatures from alpha centauri." --- Douglas Adams * @---------------------------------------------------------@ Article 17165 of rec.crafts.metalworking: Newsgroups: rec.crafts.metalworking Path: newsfeed.pitt.edu!godot.cc.duq.edu!news.duke.edu!zombie.ncsc.mil!simtel!news.kei.com!world!mv!chillon!neidorff From: neidorff@uicc.com (Bob Neidorff) Subject: Re: MIG vs. brazing for bike frames Message-ID: Sender: news@uicc.com (USENET News System) Nntp-Posting-Host: elbrus.uicc.com Organization: Unitrode Integrated Circuits Corp. X-Newsreader: TIN [version 1.2 PL2] References: <42kb9t@usenet.srv.cis.pitt.edu> Date: Mon, 11 Sep 1995 02:12:55 GMT Lines: 21 James W Gourgoutis (skoop+@pitt.edu) wrote: : Myself and 2 friends want to build/modify bicycle frames. I can't answer many questions for you, but I can give some advice. Get either or both of the following books: The Paterek Manual for Bicycle Framebuilders by Tim Paterek Published by Frame Builder' Guild, Rt. 2, Box 234, River Falls, WI 54022 Designing and Building Your Own Frameset An Illustrated Guide For Teh Amateur Bicycle Builder Richard P. Talbot, PE (C) 1984 ISBN 0-9602418-3-3 The Paterek book is looseleaf form, so not as easy to get, but, in my opinion, better. -- Bob Neidorff; Unitrode Corporation | Internet: neidorff@uicc.com 7 Continental Blvd. | Voice : (US) 603-429-8541 Merrimack, NH 03054-0399 USA | FAX : (US) 603-429-8564 Article 17127 of rec.crafts.metalworking: Newsgroups: rec.crafts.metalworking Path: newsfeed.pitt.edu!godot.cc.duq.edu!news.duke.edu!agate!howland.reston.ans.net!news.sprintlink.net!in1.uu.net!ftpbox!mothost!lmpsbbs!piscids!markl From: markl@ssd.comm.mot.com (Mark Lakomski) Subject: Re: MIG vs. brazing for bike frames Reply-To: markl@ssd.comm.mot.com Organization: Motorola LMPS Date: Fri, 8 Sep 1995 22:29:36 GMT Message-ID: <1995Sep8.222936.4295@lmpsbbs.comm.mot.com> References: <42nh49$1@mhafm.production.compuserve.com> Sender: news@lmpsbbs.comm.mot.com (LMPSBBS News Account) Nntp-Posting-Host: 145.1.157.24 Lines: 57 I don't consider myself an authority on the topic of welding, but I've done a little of each and am currently working on welding up an airframe of thinwall chrome-moly tubing simular to what you may be using. I am assuming you are using steel tubing (preferably something like 4130) otherwise TIG is about the only real practical solution. Brazing IMO will not work. The only brazing I've ever seen on a bicycle is on a lugged frame where the lugging provides most of the strength. I would imagine making lugs would be too complex of an operation for what you propose. Brazing properly ( so as to obtain the advertised tensile rating of the material ) is not as easy as you might think, especially on thin tubing. A brazed tubing butt joint probably won't even support your own weight. You may be able to buy a set of lugs for a frame at which point this might be a very attractive alternative. MIG seems too uncontrollable for this type of work. You'll wind up blowing holes through the tubes and wind up destroying a lot of stock. You might be able to get a frame done eventually, but it would take a lot of skill, practice and some luck. Stick arc on thin wall steel might be possible using tiny rods and reverse polarity but I imagine it would be more difficult then getting MIG to work. I wouldn't even attempt it. TIG might be the ideal solution, especially if you go back and heat up the frame to stress relieve the joints afterwards. The weld quality is excellent, the amount of skill required is more than MIG or Gas, the equipment and filler rod is considerably more expensive. The intense locatization of heat could have you blowing a lot of holes in the tubing that would be difficult to fix with TIG. For a big investment and a lot of practice you could produce some decent frames. Easiest to learn and probably the most flexible and forgiving welding system is still gas IMO. With a few hours of practice you could start putting together some acceptable joints. Forget the real cheap solid fuel and propane/oxygen bottle units. I've tried before and they don't put out enough heat for enough time to make a single joint properly and there is little to no flame control to prevent you from either carburizing or oxidizing the weld. Overall, if your using some decent gauge tubing MIG might be the cheapest/easiest to try, as long as you don't expect quality looking work. Best for the buck (pound/peso/lira/whatever...) would be gas. Then MIG if you ever expect to get anything that looks professional. Any of these will introduce distortion, which could make for a interesting frame. That's another reason why brazed lugged frames are so common. (One less problem to deal with). I recall being able to purchase frame lugs a few years back from a bike store. You might call around to some places that offer custom frames and inquire. Also you might want to fit up the frame and just take it to a welding shop. You may be suprised how many frames they can weld up for you for a lot less than it would cost you to buy some marginal welding equipment. If you do decide to weld yourself get some instruction. Self-taught welding is a real bad idea. You never know if you've got it right, and chance are you will never find out by trial and error. Good Luck, Mark Lakomski Hoffman Estates, IL My opinions, not Motorola's. Article 17875 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!dsinc!spool.mu.edu!howland.reston.ans.net!news-e1a.megaweb.com!newstf01.news.aol.com!newsbf02.news.aol.com!not-for-mail From: ernieleim@aol.com (ErnieLeim) Newsgroups: rec.crafts.metalworking Subject: Re: Mig Welders- Date: 1 Oct 1995 16:56:08 -0400 Organization: America Online, Inc. (1-800-827-6364) Lines: 56 Sender: root@newsbf02.news.aol.com Message-ID: <44mv98@newsbf02.news.aol.com> References: <44mgaj@newsbf02.news.aol.com> Reply-To: ernieleim@aol.com (ErnieLeim) NNTP-Posting-Host: newsbf02.mail.aol.com Little Mig welders ? It seems like I am saying the same thing about 12 times a year . Considering how many people have asked the same question about baby mig welders , I am surprised that there isn't more about them in the FAQ. One more time ...... The best of all the baby migs are the Lincoln SP-125, Miller 130, and Hobart Handler 120. All 3 are gas MIGs that can also run flux-core ( but why would you want to if you don't have to ?). I own a Handler 120 and have loved it for the last 3 years. I've welded Stainless, aluminum and steel with it without a hitch, although the aluminum capability of all the baby migs is pretty limited. For regular steel I use a 75 % argon / 25 % CO2 mix , but if I need to do a bunch of stainless I swap my 75/25 bottle in for a bottle of Helium-tri-mix. This gives hotter , cleaner welds on stainless and as long as you own your tank it doesn't cost much to swap out for a specific job and then swap back. Eventually I suppose I'll buy another tank, but for now it doesn't seem worth it. Flux-core is only recomended where a sheilding gas is likely to get blown away , such as in-the-field repairs . It is considerably nastier and means a lot of cleanup. BTW instead of buying 10 lb. ($50 - $60) spools of stainless, I buy the little 1.1 lb ($6 - $7 )spools made for spooler guns. This saves a bit of money for small jobs, but if you are doing a lot of stainless, it is cheaper per pound to buy the 10 lb spools. Remeber to match you filler metal on stainless, other wise you can get some funky welds. 308L SS filler wire is used for 304 SS. 316L SS filler wire is used for 316 SS. (The "L" stands for elevated temperature stable). The Hobart, Lincoln , and Miller machines all run close to $500 for a package . I would stay away from the cheesier brands on principle allthough some members of this newsgroup have bought them and been quite satisfied. The problem is that the low end compamies tend to have probems with waranty repairs and replacment parts. Where as the larger companies have certified repair stations all over the country. All these machines have similar max output amps and tend to max out on 1/4 inch plate steel. For thick sections just preheat to above 400 deg F. Good luck with your choice. @---------------------------------------------------------@ Ernie Leimkuhler Stagesmith Productions Custom Metal Fabrication * ABANA SCA AWS USITT IATSE local 15, 488 * Renton, WA *"For this was a time when men were REAL men, women were REAL women and small furry creatures from alpha centauri were REAL small furry creatures from alpha centauri." --- Douglas Adams * @---------------------------------------------------------@ Article 17888 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!dsinc!ub!news.kei.com!news.texas.net!news.sprintlink.net!in1.uu.net!DIALix!melbourne.DIALix.oz.au!not-for-mail From: binzel@melbourne.DIALix.oz.au (Martin Deeley) Newsgroups: rec.crafts.metalworking Subject: Welding homepages Date: 2 Oct 1995 17:05:13 +1000 Organization: DIALix Services, Melbourne, Australia. Lines: 3 Sender: binzel@melbourne.DIALix.oz.au Message-ID: <44o2v9$1@melbourne.DIALix.oz.au> NNTP-Posting-Host: binzel@melbourne.dialix.oz.au Check out http://www.binzel.com.au for good info on MIG TIG welding and Plasma cutting. Article 17984 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!gatech!howland.reston.ans.net!news.sprintlink.net!news.interserv.net!usenet From: MorseT@ncr.disa.mil (Tom Morse) Newsgroups: rec.crafts.metalworking Subject: More on MIG Welders Date: 4 Oct 1995 11:44:12 GMT Organization: InterServ News Service Lines: 12 Message-ID: <44ts2c$1vg@data.interserv.net> NNTP-Posting-Host: 164.117.177.101 X-Newsreader: AIR News 3.X (SPRY, Inc.) A couple of weeks ago I was talking to a welder-by-trade with Trane Air Conditioning in Tennessee. He said they recently tested and evaluated several 110 volt MIG welders for use in the shop and in the field. The result was that they felt the CENTURY 105/90 was the best all around unit and a good dollar value. He was so impressed that he bought one for himself (after more than ten years of not having a welder at home). The CENTURY 105/90 has 100% duty cycle on the 90 amp range and it comes with gas regulator. It also uses a standard Tweco torch and can purchased for less than $500 from several sources. Hope this helps, T.O. Morse MorseT@ncr.disa.mil Article 18031 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!uunet!in2.uu.net!news.net99.net!ratty.wolfe.net!josh From: josh@WOLFENET.COM (Joshua_Putnam) Newsgroups: rec.crafts.metalworking Subject: Re: MIG vs. brazing for bike frames Date: 5 Oct 1995 13:30:11 GMT Organization: Wolfe Internet Access, L.L.C. Lines: 36 Message-ID: <450ml3@ratty.wolfe.net> References: <44upqi$8ci@news1.svc> Reply-To: Josh@WolfeNET.com NNTP-Posting-Host: gonzo.wolfe.net In <44upqi$8ci@news1.svc> Mike Rehmus writes: >While designing a boiler, I had occasion to question the >strength of a silver-soldered joint. Looking at the >container of Silvaloy brand of silver-solder, I discovered >no statement about joint strength in the familiar 'psi' >rating we see on most welding supplies. Going on memory since I've misplaced the book, typical silver brazing alloys used on bicycle frames have strengths around 65-90 kpsi vs. around 50-70kpsi for brass. Part of this is because of the tighter tolerances of silver brazed joints -- silver flows into very tight joints better than brass does, and tighter tolerances make for stronger joints. Looking at the one spec sheet I do have handy, Harris Safety-Silv 1200 (BAg-7, 56% Ag 22% Cu 17% Zn 5% Sn) is rated at 66kpsi. It's an excellent one for bicycle construction because of its low liquidus, 1200F, and its high ductility and elongation, which help avoid cracking when joining thin tubes to stainless steel. By comparison, typical post-brazing Reynolds 531 steel has a yield stress of 80kpsi and a tensile strength of 90kpsi according to the manufacturer. This means that a silver brazed joint should be about as strong as the base material for this type of tubing. Again, this assumes good tolerances, which can't always be assumed with some hand-crafted bicycle frames. -- Josh@WolfeNet.com is Joshua Putnam / P.O. Box 13220 / Burton, WA 98013 "My other bike is a car." Article 74040 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!newsfeed.internetmci.com!uwm.edu!newsspool.doit.wisc.edu!news.doit.wisc.edu!news From: mgkepner@facstaff.wisc.edu (Melissa Kepner) Newsgroups: rec.bicycles.tech Subject: Re: Framebuilding with silver or brass? Date: Fri, 01 Mar 1996 19:52:15 GMT Organization: University of Wisconsin, System Administration Lines: 33 Message-ID: <4h7kjs@news.doit.wisc.edu> References: <4gcp8d@news.halcyon.com> NNTP-Posting-Host: f182-079.net.wisc.edu X-Newsreader: Forte Free Agent 1.0.82 ericch@halcyon.com (EricCh) wrote: >I'm curious about brazing for lugged steel frames. What is the >material of choice these days, brass or silver? I started out building with silver because it was "obvious" that there would be less heat damage with the lower temperature that the silver alloys flow at. Later, however, I was taught in the european tradition of brass brazing and learned how to do this with minimum oxidation. It may well be true that there is still greater damage to the tubing when raised to brass temps, but I feel that this method has been used successfully for decades, so it is really rather silly to worry about it. I am not a metalurgist, but I take much of what has been said about heat damage on this newsgroup with a grain of salt. I believe that the temperatures reached in brazing with either material are well above that necessary to completely anneal any steel. My experience is with 531 so I can't really comment on anything else. It remains true that a silver brazed frame is much easier to repair than one done in brass. Jim --------------------------------------------------------------------- Melissa Kepner Jim Adney mgkepner@facstaff.wisc.edu jradney@njackn.com Laura Kepner-Adney Madison, Wisconsin --------------------------------------------------------------------- Article 74446 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!newsfeed.internetmci.com!in1.uu.net!nwnews.wa.com!news.halcyon.com!usenet From: ericch@halcyon.com (EricCh) Newsgroups: rec.bicycles.tech Subject: Re: Framebuilding with silver or brass? Date: Wed, 06 Mar 1996 20:38:39 GMT Organization: Northwest Nexus Inc. Lines: 31 Message-ID: <4hkt4c@news.halcyon.com> References: <4gcp8d@news.halcyon.com> <4h7kjs@news.doit.wisc.edu> <4hkc26@usenet.srv.cis.pitt.edu> NNTP-Posting-Host: blv-pm0-ip1.halcyon.com X-Newsreader: Forte Free Agent 1.0.82 skoop+@pitt.edu (James W Gourgoutis) wrote: >The rod I ended up using for this joint was Bernz-o-matic NS-3 or >something like that. It's supposedly a Nickel-Silver alloy, and is flux >coated (blue in color). I got it mainly to practice with. It's >supposedly got a tensile strength of 80,000psi and the temp range is >1250-1750 F...which seems like the same neighborhood as most silver >filler is. (Most brass rod I've read about is up around ~1600 F or >higher.) On the back of the package, it even lists 'bicycle repair' as >a common application. I've discovered that flux-coated rod is kinda bad, >since you don't really have any control over where the flux runs, >therefore, you don't have as much control over where the filler metal flows. >My next attempt will include scraping the flux off of the rod and using a >seperate paste flux. Sounds like you're paying quite a bit for this rod. Don't scrape the flux off of it. Just go to a local welder and get some non-flux rod to play with. You can get brass for about $4/lb, or 15% silver for $15/lb. As for not having any control over where the flux runs, don't worry about it. The builder I worked with said "flux is your friend". Use the paste and smear it all over everything. It will help keep the metal from over heating. You control the flow of silver (or brass) with the heat of the torch. It will flow to the heat. I, too, read Talbot, and this contradicts what he says, but after trying it on a few frames, it works very well. The extra flux is easy to clean off with water and a wire brush. Article 73879 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!newsfeed.internetmci.com!news.msfc.nasa.gov!pendragon!tricia!news.atw.fullfeed.com!news.edsi.org!vulcan.edsi.org!not-for-mail From: jdt@vulcan.edsi.org Newsgroups: rec.bicycles.tech Subject: Re: Framebuilding with silver or brass? Date: Sat, 24 Feb 1996 03:25:00 GMT Organization: Enterprise Data Sytems Lines: 29 Distribution: world Message-ID: References: <4gcp8d@news.halcyon.com> Reply-To: jdt@edsi.org NNTP-Posting-Host: port1.edsi.org X-Newsreader: IBM NewsReader/2 v1.2.5 In <4gcp8d@news.halcyon.com>, ericch@halcyon.com (EricCh) writes: >I'm curious about brazing for lugged steel frames. What is the >material of choice these days, brass or silver? >I've checked with 2 local builders. One uses brass for everything. >The other uses brass only on the dropouts, but says he's switching to >brass everywhere due to failures in the silver brazed areas. >Talbot's book recommends brass for dropouts and silver everywhere >else. >Paterek's book says use silver everywhere. He says builders use brass >because silver is harder to use. >I'd like to hear from some frame builders. Is there a prefered >material, or is it more a matter of personal choice? Silver requires closer tolerances and better preparation (and the flux is much more irritating), but it requires less clean-up than brass and is generally easier to work with. It's a lot easier to replace tubes on a silver-brazed frame, also. I've built with both (even done all-silver Reynolds 753 frames). The biggest drawback of silver is the cost. Brass costs pennies per frame, but silver adds up fast, especially doing dropouts... -John (jdt@edsi.org) Article 73867 of rec.bicycles.tech: Path: newsfeed.pitt.edu!bb3.andrew.cmu.edu!nntp.sei.cmu.edu!news.psc.edu!scramble.lm.com!news.math.psu.edu!chi-news.cic.net!nntp.coast.net!news.kei.com!newsfeed.internetmci.com!in1.uu.net!news-relay.eworld.com!news-relay.eworld.com!not-for-mail From: philmix@eworld.com (PHILMIX) Newsgroups: rec.bicycles.tech Subject: Re: Framebuilding with silver or brass? Date: 28 Feb 1996 17:44:02 -0800 Organization: eWorld Lines: 12 Sender: root@news-relay.eworld.com Message-ID: <4h30d2@hp5.online.apple.com> References: <4gcp8d@news.halcyon.com> Reply-To: philmix@eworld.com (PHILMIX) NNTP-Posting-Host: hp5.online.apple.com Here's the deal. Silver uses less heat than brass. I don't find it harder to use than brass. Brass costs much less than silver. Silver is $10 to $12 an ounce. Brass runs about $7 a pound. The average frame used 2 to 2 1/2 oz. of brazing material. Silver cannot be used to fill voids or build up fillets. All in all silver is the preferred material HOWEVER Reynolds has a new tubing called 853 that must be brass brazed or TIG welded because it must be brought up to a certain temp. to gain its proper strength. Phil Brown Article 73134 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!newsfeed.internetmci.com!in2.uu.net!nwlink.com!tsunami.ixa.net!news.aa.net!ratty.wolfe.net!news1.wolfe.net!josh From: josh@WOLFENET.COM (Joshua_Putnam) Newsgroups: rec.bicycles.tech Subject: Re: Reynolds 531 durability Date: 20 Feb 1996 15:03:15 GMT Organization: Wolfe Internet Access, L.L.C. Lines: 40 Message-ID: <4gcnrj@news1.wolfe.net> References: <4e8brd@newsbf02.news.aol.com> <31238345.57A6@atmos.washington.edu> <4g0grq@hermes.acs.unt.edu> <4g6cg0@news1.wolfe.net> <639bMouKYgB@quijote.in-berlin.d e> Reply-To: Josh@WolfeNET.com NNTP-Posting-Host: gonzo.wolfenet.com In <639bMouKYgB@quijote.in-berlin.de> hajo@quijote.in-berlin.de (Hans-Joachim Zierke) writes: >Joshua_Putnam writes: >> In fact, 531 frames may well be more durable than Columbus >> frames when poorly built, simply because the Reynolds steel >> can stand overheating better than heat-treated Columbus >> can. 531 can be brass brazed at over 1900F without >> significant loss of strength, >Hmmh... this must be a wonder material. I guess it wasn't created by >engineers, but by salespeople. >> while Colombus says not to go >> over 1290F. >Sounds like honest info. It's not that Reynolds encourages going over normal brazing temperatures, but that 531 isn't a heat treated alloy, so you're not losing the added strength of heat treating. There definitely is a loss of strength from overheating, just not as large a loss as with heat-treated CrMo. For 531 tubes, Reynolds suggests a maximum liquidus of 1700F. For 753, they say not to go over 1290F, the same as for Columbus heat-treated steels. They're ven more conservative on the rear stays of 731, 653, and 708 tube sets, saying not to go over about 1200F. On the other hand, for their 525 CrMo tube set, they say temperatures of 2000F are acceptable. -- Josh@WolfeNet.com is Joshua Putnam / P.O. Box 13220 / Burton, WA 98013 "My other bike is a car." New & used bike parts for sale: finger Joshua_Putnam@WolfeNet.com for list. Article 53963 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!howland.reston.ans.net!swrinde!cs.utexas.edu!news.sprintlink.net!ratty.wolfe.net!josh From: josh@Wolfe.NET (Joshua_Putnam) Newsgroups: rec.bicycles.tech Subject: Re: Building your on bicycle frame Date: 11 Jul 1995 17:22:14 GMT Organization: Wolfe Internet Access, L.L.C. Lines: 45 Message-ID: <3tuc06@news1.wolfe.net> References: <3ts80a@fido.asd.sgi.com> NNTP-Posting-Host: gonzo.wolfe.net In <3ts80a@fido.asd.sgi.com> Richard Hedges writes: >I am interested in building my own bicycle frame. I would like >to build a road bicycle. >2. Are there any good reference materials? Richard Talbot's book _Designing and Building Your Own Frameset: An Illustrated Guide for the Amateur Bicycle Builder_, is an excellent introduction to building your own lugged road frame. Talbot himself was a novice when he began the project, and did all the work at home with home-made jigs and minimal equipment, so the book addresses many points that apply to the amateur but not to the professional frame builder who can afford, for example, a proper frame-tube mitering tool. Any good bike shop should be able to order you a copy of the book from United Bicycle Tool in Oregon, or you might find it at your local library. At a more advanced level, Tim Paterek's _The Paterek Manual_ goes into even more detail about design, materials, and equipment. It's also much more expensive. I'd suggest looking in your local library, or asking a local frame builder if you can read his copy. >3. Are there any classes, which, as a part of the class, you would > build your own frame? Ti Cycles in Seattle offers such a class -- there's an excellent writeup of it in the rec.bicycles.* archives (ftp address in the FAQ). >4. Where do you get tubing, lugs, dropouts, ...etc. ? Talbot's book lists several sources, some out-of-date, unfortunately. (When he wrote the book, Nashbar still sold frame tubing, brazing supplies, and Nervex lugs!) -- Josh@WOLFE.net is Joshua Putnam / P.O. Box 13220 / Burton, WA 98013 "My other bike is a car." Bike parts for sale: finger Joshua_Putnam@gonzo.wolfe.net for list. Article 54693 of rec.bicycles.tech: Path: newsfeed.pitt.edu!godot.cc.duq.edu!news.duke.edu!agate!howland.reston.ans.net!news.sprintlink.net!ratty.wolfe.net!josh From: josh@Wolfe.NET (Joshua_Putnam) Newsgroups: rec.bicycles.tech Subject: Re: Source of frame building materials Date: 19 Jul 1995 15:30:19 GMT Organization: Wolfe Internet Access, L.L.C. Lines: 32 Message-ID: <3uj8ec@news1.wolfe.net> References: <3uh9ld@fido.asd.sgi.com> <3uj8ba@news1.wolfe.net> NNTP-Posting-Host: gonzo.wolfe.net In <3uh9ld@fido.asd.sgi.com> Richard Hedges writes: >I am looking to build a road frame. >Can anyone point me to sources of frame tubing, lugs, dropouts, >and other miscellaneous parts? You can get almost everything you need from Henry James Bicycles, Inc. He's most famous for his beautiful and distinctive fork crowns and stainless steel dropouts, but his cast lugs are also top-quality and reasonably priced. The company also distributes nine different models of True Temper tubing, either in sets or by the piece. Also brazing rod, frame and fork jigs, and books: both the Paterek frame manual and Talbot's guide for amateur frame builders. If you just want to build one frame for yourself, I'd strongly recommend the Talbot book. Henry James Bicycles, Inc 704 Elvira Ave. Redondo Beach, CA 90277 310-540-1552 or fax 310-316-8202 Disclaimer: I have no relationship with Henry James Bicycles other than >really appreciating the quality and aesthetics of his >products. -- Josh@WOLFE.net is Joshua Putnam / P.O. Box 13220 / Burton, WA 98013 "My other bike is a car." Bike parts for sale: finger Joshua_Putnam@gonzo.wolfe.net for list. Article 54664 of rec.bicycles.tech: Path: newsfeed.pitt.edu!dsinc!ub!news.kei.com!newshost.marcam.com!usc!nic-nac.CSU.net!news.Cerritos.edu!vax.cerritos.edu!templ002 From: templ002@cerritos.edu (TEMPLETON ROBERT M) Newsgroups: rec.bicycles.tech Subject: Re: Source of frame building materials Date: 18 Jul 95 21:22:44 PST Organization: Cerritos College, Norwalk CA Lines: 27 Message-ID: <1995Jul18.212244.1@vax.cerritos.edu> References: <3uh9ld@fido.asd.sgi.com> NNTP-Posting-Host: white.cerritos.edu In article <3uh9ld@fido.asd.sgi.com>, Richard Hedges writes: > I am looking to build a road frame. > > Can anyone point me to sources of frame tubing, lugs, dropouts, > and other miscellaneous parts? > > > Thanks, > A few sources that im familiar with is: 1. Cyclo-Pedia Inc. PO Box 884 Adrian, MI 49221 2. The Dillsburg Aeroplane Works 114 Sawmill Rd. Dillsburg, PA 17019 3. Gaerlan, Inc. 838 Grant Ave., Suite 410 San Francisco, CA 94108 Some of them charge a very small fee for their catalogs. Like a dollar or two. Hope this helps. Robby Article 54693 of rec.bicycles.tech: Path: newsfeed.pitt.edu!godot.cc.duq.edu!news.duke.edu!agate!howland.reston.ans.net!news.sprintlink.net!ratty.wolfe.net!josh From: josh@Wolfe.NET (Joshua_Putnam) Newsgroups: rec.bicycles.tech Subject: Re: Source of frame building materials Date: 19 Jul 1995 15:30:19 GMT Organization: Wolfe Internet Access, L.L.C. Lines: 32 Message-ID: <3uj8ec@news1.wolfe.net> References: <3uh9ld@fido.asd.sgi.com> <3uj8ba@news1.wolfe.net> NNTP-Posting-Host: gonzo.wolfe.net In <3uh9ld@fido.asd.sgi.com> Richard Hedges writes: >I am looking to build a road frame. >Can anyone point me to sources of frame tubing, lugs, dropouts, >and other miscellaneous parts? You can get almost everything you need from Henry James Bicycles, Inc. He's most famous for his beautiful and distinctive fork crowns and stainless steel dropouts, but his cast lugs are also top-quality and reasonably priced. The company also distributes nine different models of True Temper tubing, either in sets or by the piece. Also brazing rod, frame and fork jigs, and books: both the Paterek frame manual and Talbot's guide for amateur frame builders. If you just want to build one frame for yourself, I'd strongly recommend the Talbot book. Henry James Bicycles, Inc 704 Elvira Ave. Redondo Beach, CA 90277 310-540-1552 or fax 310-316-8202 Disclaimer: I have no relationship with Henry James Bicycles other than >really appreciating the quality and aesthetics of his >products. -- Josh@WOLFE.net is Joshua Putnam / P.O. Box 13220 / Burton, WA 98013 "My other bike is a car." Bike parts for sale: finger Joshua_Putnam@gonzo.wolfe.net for list. Article 54664 of rec.bicycles.tech: Path: newsfeed.pitt.edu!dsinc!ub!news.kei.com!newshost.marcam.com!usc!nic-nac.CSU.net!news.Cerritos.edu!vax.cerritos.edu!templ002 From: templ002@cerritos.edu (TEMPLETON ROBERT M) Newsgroups: rec.bicycles.tech Subject: Re: Source of frame building materials Date: 18 Jul 95 21:22:44 PST Organization: Cerritos College, Norwalk CA Lines: 27 Message-ID: <1995Jul18.212244.1@vax.cerritos.edu> References: <3uh9ld@fido.asd.sgi.com> NNTP-Posting-Host: white.cerritos.edu In article <3uh9ld@fido.asd.sgi.com>, Richard Hedges writes: > I am looking to build a road frame. > > Can anyone point me to sources of frame tubing, lugs, dropouts, > and other miscellaneous parts? > > > Thanks, > A few sources that im familiar with is: 1. Cyclo-Pedia Inc. PO Box 884 Adrian, MI 49221 2. The Dillsburg Aeroplane Works 114 Sawmill Rd. Dillsburg, PA 17019 3. Gaerlan, Inc. 838 Grant Ave., Suite 410 San Francisco, CA 94108 Some of them charge a very small fee for their catalogs. Like a dollar or two. Hope this helps. Robby Article 57592 of rec.bicycles.tech: Path: newsfeed.pitt.edu!skoop From: skoop+@pitt.edu (James W Gourgoutis) Newsgroups: rec.bicycles.tech Subject: MIG vs. TIG--why??? Date: 22 Aug 1995 16:40:06 GMT Organization: University of Pittsburgh Lines: 22 Message-ID: <41d196@usenet.srv.cis.pitt.edu> NNTP-Posting-Host: unixs5.cis.pitt.edu I'm sure that this has been brought up before, but... *Why* is TIG welding preferred over MIG welding for bike frames'n'such? Myself and 2 friends are considering purchasing a small, portable MIG welder to get our feet wet (i.e. learn how to weld), and eventually to use on weekend bike projects, so I'm wondering...if you can't (or shouldn't) weld bikes with MIG, then I guess we shouldn't even bother. Is there even such a thing as a small, portable *TIG* welder? As alway, any advice is appreciated. Thanks, Jim . . . . James Gourgoutis [http://www.pitt.edu/~skoop] Graduate School of Mechanical Engineering ~~ ,o University of Pittsburgh / Pittsburgh, PA ~~ -\<, "Why am I so late? Couldn't decide which bike to ride!" ~~ ( )/( ) Article 57613 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!howland.reston.ans.net!nntp.crl.com!crl2.crl.com!not-for-mail From: lapdog@crl.com (Gary Helfrich) Newsgroups: rec.bicycles.tech Subject: Re: MIG vs. TIG--why??? Date: 22 Aug 1995 12:49:07 -0700 Organization: CRL Dialup Internet Access (415) 705-6060 [Login: guest] Lines: 32 Message-ID: <41dcbj@crl2.crl.com> References: <41d196@usenet.srv.cis.pitt.edu> NNTP-Posting-Host: crl2.crl.com X-Newsreader: TIN [version 1.2 PL2] James W Gourgoutis (skoop+@pitt.edu) wrote: : I'm sure that this has been brought up before, but... : *Why* is TIG welding preferred over MIG welding for bike frames'n'such? : Myself and 2 friends are considering purchasing a small, portable MIG : welder to get our feet wet (i.e. learn how to weld), and eventually to : use on weekend bike projects, so I'm wondering...if you can't (or : shouldn't) weld bikes with MIG, then I guess we shouldn't even bother. MIG welding is very difficult when sub 1mm material is involved as in bike building. There is MIG equipment that can weld material this thin, but you are looking at over $10K for the equipment and it is not very portable. Even if you spent the money, you would find the equipment impossible to manipulate through all the joints in the bike. There are multi-process machines made by Powcon, and Miller. These machines will allow you to run either MIG or TIG, and are around $4500. I have the Miller machine (XMT-300) and am very happy with it. The nice thing is that you can weld frames in TIG mode, and then MIG weld 25mm aluminum plate for a fixture with the same machine. : Is there even such a thing as a small, portable *TIG* welder? There are several machines made. At United Bike Institute we use Miller Maxstar 152's. They are very reliable, and seem to work better than some of Millers big machines (like the Syncowave) for welding thin tubing. Miller also makes a machine called the EconoTig which I would avoid like the plague. It seem like a great deal, but it has almost no low range control. Does a great job blowing holes in tubes, though. Gary Helfrich Arctos Machine Article 16373 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!gatech!news.sprintlink.net!newsfeed.internetmci.com!server2.ols.net!usenet From: mike@ols.net (Mike Rembisz) Newsgroups: rec.crafts.metalworking Subject: Speaking of MIG Welders Date: Sun, 20 Aug 1995 03:09:13 GMT Organization: Online South Incorporated Lines: 24 Message-ID: <4168pq@server2.ols.net> NNTP-Posting-Host: 205.139.152.128 X-Newsreader: Forte Free Agent 1.0.82 A couple of weeks ago I requested info on Mig welders as they pertain to welding auto bodies and I received a number of responses both pro and con regarding low amperage welders. Well I bought one, a Century 90 amp MIG welder and I said I would keep you informed of my findings. Well here goes... I welded in a floor pan in my '67 fastback! It took me all day to do the job, a lot of time was needed to cut out the old one and prepare the surface for the new one but the welding went ok. The 90 amp welder has more than enough power to weld body metal; in fact , if you don't watch what you're doing it's easy to burn a hole in the metal on setting 2. As far as the low duty cycle, I discovered that the Miller, Lincoln, Century, Hobart all have low duty cycles; about 15-20% at their highest power. But sheet metal is done on 1/4 or 1/2 power! and at least in my case did not weld for more that 30 seconds at a time and then I stopped and checked my work ( usually crooked). If any of you have been wanting to be weekend welders, go for it! My welder cost $299 at Sam's Club and then I spent $100 for a 40 cubic foot tank (the book says only a 20 cu. ft tank will fit but don't believe it. The cost is only $20 more and you get twice the shielding gas, enough for about 2.5 hours and believe me that's a lot of welding!!!) The welder works fine, now I just have to learn to weld a straight line!!! Mike Article 57925 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!howland.reston.ans.net!swrinde!tank.news.pipex.net!pipex!news.sprintlink.net!nntp.earthlink.net!usenet From: Walter Gomes Newsgroups: rec.bicycles.tech Subject: RE: MIG vs. TIG-why??? Date: 26 Aug 1995 04:52:51 GMT Organization: very little Lines: 39 Message-ID: <41m9b3@mars.earthlink.net> NNTP-Posting-Host: wgomes.earthlink.net Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Transfer-Encoding: 7bit X-Mailer: Mozilla 1.2b2 (Windows; I; 16bit) To: skoop+@pitt.edu skoop+@pitt.edu (James W Gourgoutis) wrote: >I'm sure that this has been brought up before, but... > >*Why* is TIG welding preferred over MIG welding for bike frames'n'such? Hey Jim, The basic difference in tig vs. mig is control. With tig you get much better heat control, and a much finer bead than wire-feed (mig). Very good weldors (few and far between) can weld a joint so fine that its almost indestinguishable [without grinding](BTW a weldor is one who welds, not the machine). Using a tig torch is much akin to using a oxy/acetylene torch in that you control the heat (by varying the freq. with the foot pedal or thumb wheel) and control the amount of rod you add to the weld puddle. With a good tig machine its said you can (I can't) weld a razor blade to a boat anchor. The idea being to make a very hot spot over a very small area and control it. Tig is also the best way to weld aluminum and stainless steel (no, not to each other) On the other hand, mig has the current (heat) and wire speed (rate of rod added to the puddle) set at the machine. Again, a good weldor can use this effectively, but us mortals can make use of the better control to create a better weld. Mig is useful in coarse and/or production work (it's much faster than tig) If I were you (which I'm not) I'd try to score a ac/dc tig machine (or a ac/dc welder and an outboard high freq. aircooled torch). Don't get me wrong, Mig welders work well, and are probably easier for a beginner to use. But for a fine welding (eg. bicycle frames, etc.) a good tig has it beat hands down. You might check rec.crafts.metalworking seems I saw a post on how to build a tig using an automobile alternator (?) Hope this helps! Walter Article 57964 of rec.bicycles.tech: Path: newsfeed.pitt.edu!godot.cc.duq.edu!news.duke.edu!agate!howland.reston.ans.net!nntp.crl.com!crl12.crl.com!not-for-mail From: lapdog@crl.com (Gary Helfrich) Newsgroups: rec.bicycles.tech Subject: Re: MIG vs. TIG-why??? Date: 26 Aug 1995 20:37:49 -0700 Organization: CRL Dialup Internet Access (415) 705-6060 [Login: guest] Lines: 25 Message-ID: <41opad$8o8@crl12.crl.com> References: <41m9bi@mars.earthlink.net> NNTP-Posting-Host: crl12.crl.com X-Newsreader: TIN [version 1.2 PL2] Walter Gomes (wgomes@earthlink.net) wrote: : skoop+@pitt.edu (James W Gourgoutis) wrote: : >I'm sure that this has been brought up before, but... : > : >*Why* is TIG welding preferred over MIG welding for bike frames'n'such? : Hey Jim, : The basic difference in tig vs. mig is control. With tig you get much : better heat control, and a much finer bead than wire-feed (mig). : Very good weldors (few and far between) can weld a joint so fine that : its almost indestinguishable [without grinding](BTW a weldor is one who : welds, not the machine). It is true that the skill of the operator will make up for many shortcomings in the equipment. I doubt that any weldor (is that like a Realtor?) can weld .5 mm steel with a mig setup in the confined spaces that exist in a bike frame. Even if they can, the beads will lood like something that came out of Huffy on a bad day. Stick with tig for welding bike frames. Gary Helfrich Arctos Machine Article 16462 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!gatech!howland.reston.ans.net!ix.netcom.com!netnews From: jhre@ix.netcom.com (Jim Harvey) Newsgroups: rec.crafts.metalworking Subject: Re: Gas weld auto tube frame ? Date: Tue, 22 Aug 1995 16:56:10 GMT Organization: Harvey Racing Engines Lines: 36 Message-ID: <41co1r@ixnews3.ix.netcom.com> References: <41aj0h@news1.svc> Reply-To: jhre@ix.netcom.com NNTP-Posting-Host: ix-li1-30.ix.netcom.com X-Newsreader: Forte Agent .99.82 Mike Rehmus wrote: >The answer is always yes, if you know what you are doing which, in this case, >means lots of practice and maybe a class or two. It is so easy to make a >good-looking but crappy, dangerous weld where, in a critial area, the weld >will fail under load. Not so bad if you are building fences. Potentially >a disaster if you are wheeling a 3/4 ton set of wheels down the road and >a weld breaks. I could'nt agree with Mike more. I will go one step further and say FORGET about gas welding your frame. If you want to get that involved in making a street rod, buy a MIG welder. The amount of time that you will have to invest in learning how to make a safe weld with a mig is far less that that of a gas torch. Use only Mild Steel for the frame. If you go Chrome Moly you have to weld it with TIG (many will argue with me on this but they are wrong - All Sanctioning bodies REQUIRE that Chrome moly frames/roll bars be TIG welded. There is a reason for that (The average guy does not have a TIG welder, so a professional weldor is called) And as Mike said, not to be taken as a flame, but if you even had to ask this question, you are not ready to undertake this project. I would suggest that you bone up on the subject and realize the enormous amount of work that goes into a project like this. Not saying that it can't be done, just that a lot more education is required. Jim Harvey Article 16686 of rec.crafts.metalworking: Newsgroups: rec.crafts.metalworking Path: newsfeed.pitt.edu!dsinc!spool.mu.edu!bloom-beacon.mit.edu!news.kei.com!simtel!harbinger.cc.monash.edu.au!news.cs.su.oz.au!metro!news.ci.com.au!wabbit.cc.uow.edu.au!news.nsw.CSIRO.AU!its.csiro.au!peter From: peter@prospect.anprod.csiro.au (Peter Wiley) Subject: Re: Gas weld auto tube frame ? Message-ID: Sender: news@its.csiro.au (News Manager) Nntp-Posting-Host: alpha.prospect.anprod.csiro.au Organization: CSIRO Division of Animal Production, Prospect NSW References: <41aj0h@news1.svc> <41co1r@ixnews3.ix.netcom.com> Date: Mon, 28 Aug 1995 00:34:19 GMT Lines: 20 In article <41co1r@ixnews3.ix.netcom.com> jhre@ix.netcom.com writes: >If you want to get that involved in making a street rod, buy a MIG >welder. The amount of time that you will have to invest in learning >how to make a safe weld with a mig is far less that that of a gas >torch. As a person who has trade quals in most of the welding disciplines, I'd agree MIG is easier than gas. However, it's even easier to do a crappy but good-looking MIG weld where you don't get sufficient penetration of the parent material. When I did my courses some years ago, MIG wasn't rated as suitable for pressure vessel work, just for this reason. We used stick, gas and TIG for pressure vessel certification. Took me 2 years, 2 nights/week to learn to weld to pressure standards, in all positions, using the 4 common methods (sub arc too). Not something you want to rush into if a weld failure is going to risk someone's life or health. Peter Wiley Article 16663 of rec.crafts.metalworking: Path: newsfeed.pitt.edu!godot.cc.duq.edu!news.duke.edu!agate!howland.reston.ans.net!news.sprintlink.net!in1.uu.net!news.compuserve.com!news.production.compuserve.com!news From: Brent Vinson <73762.1017@CompuServe.COM> Newsgroups: rec.crafts.metalworking Subject: Re: Gas weld auto tube frame ? Date: 27 Aug 1995 03:26:42 GMT Organization: CompuServe, Inc. (1-800-689-0736) Lines: 14 Message-ID: <41ooli$5v1$1@mhade.production.compuserve.com> References: Simon, Use a MIG to weld your tube frame. Faster and less heat stress on the metal. We do this for a living. Write if you have any specific questions about auto fabrication. Good luck! Brent -- Brent Vinson Article 50274 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!howland.reston.ans.net!ix.netcom.com!netnews From: yankypom@ix.netcom.com (Gregory Towers) Newsgroups: rec.bicycles.tech,rec.crafts.metalworking Subject: help wanted re TIG welding bike frames. Date: 27 May 1995 08:10:03 GMT Organization: Netcom Lines: 15 Distribution: world Message-ID: <3q6mor@ixnews4.ix.netcom.com> NNTP-Posting-Host: ix-sf5-17.ix.netcom.com Xref: newsfeed.pitt.edu rec.bicycles.tech:50274 rec.crafts.metalworking:13053 I have been practicing TIG welding thin wall tubing in anticipation of making a bicycle but I am finding it hard to get a pretty bead. Also I am wondering if melt through is acceptable. I know that the head tube and seat tube are reamed before the painting operation so is it OK if there is some melt through in these places? If I weld slow and cold then the HAZ is wide and the bead kind of ugly and "cold" looking. If I weld hot and fast and hold a slightly longer arc length then things look better but I get some melt through. Which is preferred? Should I use copper back up bars in the head tube and seat tube? The tubing is CrMo (4130) and wall thickness is around .032 for the thinner tubes, my machine is set at around 65 amps. Any hints and tips would be greatly appreciated. Thanks, Greg (yankypom@ix.netcom.com) Article 50283 of rec.bicycles.tech: Path: newsfeed.pitt.edu!gatech!howland.reston.ans.net!nntp.crl.com!crl4.crl.com!not-for-mail From: lapdog@crl.com (Gary Helfrich) Newsgroups: rec.bicycles.tech,rec.crafts.metalworking Subject: Re: help wanted re TIG welding bike frames. Followup-To: rec.bicycles.tech,rec.crafts.metalworking Date: 27 May 1995 08:54:27 -0700 Organization: CRL Dialup Internet Access (415) 705-6060 [Login: guest] Lines: 36 Distribution: world Message-ID: <3q7hvj@crl4.crl.com> References: <3q6mor@ixnews4.ix.netcom.com> NNTP-Posting-Host: crl4.crl.com X-Newsreader: TIN [version 1.2 PL2] Xref: newsfeed.pitt.edu rec.bicycles.tech:50283 rec.crafts.metalworking:13059 Gregory Towers (yankypom@ix.netcom.com) wrote: : I have been practicing TIG welding thin wall tubing in anticipation : of making a bicycle but I am finding it hard to get a pretty bead. : Also I am wondering if melt through is acceptable. I know that the : head tube and seat tube are reamed before the painting operation so is : it OK if there is some melt through in these places? : If I weld slow and cold then the HAZ is wide and the bead kind of : ugly and "cold" looking. : If I weld hot and fast and hold a slightly longer arc length then : things look better but I get some melt through. Melt through will kill you frame finishing tools. Try to avoid it. With a 1/16 2% tungsten (the most common for framebuilding) you should keep a 1 mm arc length at all times. Holding a constant arc length is one of most difficult skills for a beginner to master. Remember that the energy in the arc goes UP as you pull away, so pulling back is a bad habit. Use the foot pedal for your heat control. : Which is preferred? Should I use copper back up bars in the : head tube and seat tube? : The tubing is CrMo (4130) and wall thickness is around .032 for the : thinner tubes, my machine is set at around 65 amps. The way to control your HAZ is to move quickly. For .8mm tubing I use 95 amps (on a Maxstar 151) and a 1 mm wire. If you can afford one, a pulser will help you travel even faster and still control your penetration. An experienced welder can do high quality work without using backup bars. They are kinda like training wheels...someday you're going to have to take them off. If you are really rolling in the dough, you might want to try an inverter type power source. These machines will respond to your foot control far quicker than conventional machines, and they are very energy efficient. Gary Helfrich Arctos Machine From rhorvat@tbd161.tbd.ford.com Fri Jul 14 09:20:38 EDT 1995 Article: 54263 of rec.bicycles.tech Path: newsfeed.pitt.edu!gatech!newsxfer.itd.umich.edu!jobone!fiesta.srl.ford.com!news.tbd.ford.com!tbd161.tbd.ford.com!rhorvat From: Robert Horvatich Newsgroups: rec.bicycles.tech Subject: Re: I wanna learn how to weld...need advice Date: Thu, 13 Jul 1995 16:03:50 -0400 Organization: Ford Motor Co. -- Standard disclaimers apply. Lines: 44 Message-ID: References: <3u3o6u@usenet.srv.cis.pitt.edu> NNTP-Posting-Host: tbd161.tbd.ford.com Mime-Version: 1.0 Content-Type: TEXT/PLAIN; charset=US-ASCII In-Reply-To: <3u3o6u@usenet.srv.cis.pitt.edu> On 13 Jul 1995, James W Gourgoutis wrote: > Folks: > > In the continuing series of my rants on getting a job in the bike industry, > I have a question: > > To further boost my chances in getting a job in this field, I'm thinking > about learning how to weld during the coming winter. I'm currently > gathering information from my local community college on course > availability, costs, etc. A course is a good place to start. Lincoln Electric puts out a very good hand book on all sorts of welding techniques. This should help familiarize you with the process as well as provide technical support for filler alloys and shielding gas mixtures. Most of my knowledge of welding techniques have come from technicians, books, as well as practice. With the proper setup and some practice, you should be able to perform acceptable work. > Does this sound like a good idea? My rationale is that if I ever get to > a point in my life where I have the opportunity to build my own frame(s), > I want to learn how to weld. I also think that it would go well with my > ME degree. Yes, it will go good with your ME degree. I would have to wonder just a bit that if the bike industry is so strong right now and you are having such a hard time finding a job, how secure is that industry. > *IF* this sounds like a good plan, is there any area of welding > technology I should concentrate on? The course description guide from my > local community college describes a variety of classes, and I'm a bit > lost on which one(s) to take. TIG welding should be the primary focus of your studies. There are a lot of variations to this process that can be more technique than science. Rob email: |"You can't take life too seriously, rhorvat@tbd161.tbd.ford.com | you don't get out alive." Bugs Bunny From mkrieg@well.com Fri Jul 14 09:21:23 EDT 1995 Article: 54237 of rec.bicycles.tech Path: newsfeed.pitt.edu!uunet!in1.uu.net!news1.digital.com!nntp-hub2.barrnet.net!nntp-ucb.barrnet.net!well!usenet From: mkrieg@well.com (Michael Krieg) Newsgroups: rec.bicycles.tech Subject: Re: I wanna learn how to weld...need advice Date: Fri, 14 Jul 1995 00:42:07 GMT Organization: The Whole Earth 'Lectronic Link, Sausalito, CA Lines: 18 Message-ID: <3u4e3k@nkosi.well.com> References: <3u3o6u@usenet.srv.cis.pitt.edu> NNTP-Posting-Host: cust16.max5.san-francisco.ca.ms.uu.net X-Newsreader: Forte Free Agent v0.71 skoop+@pitt.edu (James W Gourgoutis) wrote: >To further boost my chances in getting a job in this field, I'm thinking >about learning how to weld during the coming winter. I'm currently >gathering information from my local community college on course >availability, costs, etc. >Does this sound like a good idea? My rationale is that if I ever get to >a point in my life where I have the opportunity to build my own frame(s), >I want to learn how to weld. I took a couple of welding courses at a community college a few years ago, just for the heck of it. It was lots of fun, and I actually got pretty good, but I sure wouldn't trust my life to my own welds. From mbushore@icaen.uiowa.edu Fri Jul 14 10:06:02 EDT 1995 Article: 54262 of rec.bicycles.tech Path: newsfeed.pitt.edu!gatech!swrinde!cs.utexas.edu!math.ohio-state.edu!hobbes.physics.uiowa.edu!news.uiowa.edu!news1.icaen!icaen.uiowa.edu!mbushore From: mbushore@icaen.uiowa.edu Newsgroups: rec.bicycles.tech Subject: Re: I wanna learn how to weld...need advice Date: 14 Jul 1995 04:16:16 GMT Organization: is for the weak of mind and faint of heart Lines: 109 Sender: mbushore@icaen.uiowa.edu (dammit) Distribution: usa Message-ID: <3u4r2g@server05.icaen.uiowa.edu> References: <3u3o6u@usenet.srv.cis.pitt.edu> NNTP-Posting-Host: l-ecn014.icaen.uiowa.edu Keywords: watch the puddle closely and keep moving In article <3u3o6u@usenet.srv.cis.pitt.edu>, skoop+@pitt.edu (James W Gourgoutis) writes: |> Folks: |> |> In the continuing series of my rants on getting a job in the bike industry, |> I have a question: |> |> To further boost my chances in getting a job in this field, I'm thinking |> about learning how to weld during the coming winter. I'm currently |> gathering information from my local community college on course |> availability, costs, etc. |> |> Does this sound like a good idea? My rationale is that if I ever get to |> a point in my life where I have the opportunity to build my own frame(s), |> I want to learn how to weld. I also think that it would go well with my |> ME degree. Learning to weld is good from a practical standpoint. Knowing firsthand the limitations of any process can help out when you are in the design process. You will avoid desiging joints that are impossible/difficult to miter, jig up, and/or weld. Half of welding is in welding; half is in setup and fixturing. The last two-thirds is battling eye-strain and fatigue. Some other things to think about, which are,of course, common sense. 1) Lives will be dependant on your welding. This is sort of a heavy thought at times (at least it was for me, but later drowned out by heavy doses of the Beastie Boys and Dr. Pepper). This basically meant I practiced my ass off and was really anal about things until I knew I knew what I was doing. Death is one of the few things I get anal about..... 2) Someone out there already knows how to weld better than you ever will, but perhaps doesn't know jack about being an engineer. Its the "Jack of all trades, master of none" thing going on. I personally love to weld, but I know my limitations and where my skills are best used. (I personally excell at sleeping and bullshitting people, YMMV) Learn to weld to enhance your life and your understanding of the welding process, etc, but be somewhat realistic in your goals until you are at least able to feed yourself three times a week. If you want to get good enough to build frames, then by all means commit to it and go for it, but I honestly feel it will be rare that you will be in the situation where you will be both a welder and an engineer. Its simply too easy to hire good welders. Case(s) in point -> Does Joe Murray build all of the new Voodoos? Does Joe B. build all of the Breezers? Does K. B. build all of the Bontragers? |> *IF* this sounds like a good plan, is there any area of welding |> technology I should concentrate on? The course description guide from my |> local community college describes a variety of classes, and I'm a bit |> lost on which one(s) to take. Which ones are offered? The current trend is towards TIG(GTAW) I think. TIG welding steel is pretty easy to pick up on, and is far more forgiving than welding AL or Ti. Not that steel can't be complicated, but I think its much easier. You might also want to know how to braze for doing such things as braze ons, dropouts, etc. Once you get your two hands talking to each other, TIG welding and brazing use many of the same motions. Don't waste your time with learing to stick weld(SAW), or wire weld(MIG/GMAW) unless you feel some burning desire, or are preparing for a stint working on a farm or an auto repair shop. |> Unfortunately, there is NO way I can learn how to weld at the University |> of Pittsburgh...it's simply not offered. I find out 7 years too late that I |> went to the wrong school! Community colleges and tech colleges are excellent for filling in the practical gaps left by the four(or 7 as the case may be;) ) year schools. Extra- and Co-curricular(sp) activities such as the SAE design contests are a groovy way to pick these skills up with only an investment in time. I personally would be wary of any of my profs here using power tools. I don't think that I am going to run out and trade in my M.E. wannadegree for a full time welding job, though. The last time I welded anything (a stainless steel femur implant for torsional testing, for these keeping track of the score at home) for money, I got $6.00. Oddly enough, its the same I get to sweep the floors in the shop,too. ( I _can_ TIG weld holding the torch with my right foot- not a skill in high demand, but surely one I could charge dearly for...) |> Thanks for any and all advice! |> |> Regards, |> |> Jim While you are at, consider learning about how to work with other machine tools. The vetical mill and lathe come to mind. A little experience with these machines goes a long way. If you can talk intelligently with the machinist working on your latest project, you will avoid becoming the subject of breaktime tales. If you get good, you can even forgo the machinist completely (if you have time). Regards, Mattttt From skoop+@pitt.edu Fri Jul 14 10:06:07 EDT 1995 Article: 54279 of rec.bicycles.tech Path: newsfeed.pitt.edu!skoop From: skoop+@pitt.edu (James W Gourgoutis) Newsgroups: rec.bicycles.tech Subject: Re: I wanna learn how to weld...need advice Date: 14 Jul 1995 14:05:48 GMT Organization: University of Pittsburgh Lines: 164 Sender: skoop+@pitt.edu Distribution: usa Message-ID: <3u5tjs@usenet.srv.cis.pitt.edu> References: <3u3o6u@usenet.srv.cis.pitt.edu> <3u4r2g@server05.icaen.uiowa.edu> NNTP-Posting-Host: unixs5.cis.pitt.edu Keywords: watch the puddle closely and keep moving In article <3u4r2g@server05.icaen.uiowa.edu>, wrote: > >Learning to weld is good from a practical standpoint. >Knowing firsthand the limitations of any process can help out when >you are in the design process. You will avoid desiging joints that >are impossible/difficult to miter, jig up, and/or weld. Right. That's part of the reason I want to do this. >Some other things to think about, which are,of course, common sense. > > I personally love to weld, but I know my limitations and where my skills > are best used. (I personally excell at sleeping and bullshitting people, YMMV) > Learn to weld to enhance your life and your understanding of the welding > process, etc, but be somewhat realistic in your goals until you are at > least able to feed yourself three times a week. > > If you want to get good enough to build frames, then by all means commit > to it and go for it, but I honestly feel it will be rare that you will be > in the situation where you will be both a welder and an engineer. > Its simply too easy to hire good welders. Of course. My aspirations are more to go work for somebody else, rather than becoming my own frame builder. Ideally, I want to get a job doing *something* of a technical nature in a mid-sized bike manufacturing company. (I'm not super-picky, in case you didn't notice. :) ) I realize that it takes many, many years of practice and experience to get to the point where I could actually be *hired* as a professional welder (i.e. I know that one of KB's guys used to work in the aircraft industry). I just want to be good enough to be able to hack my own ideas together. (ala Chunk 666 if you know what that means). I've been conversing with a few other engineering students/etc. from this newsgroup, and many of them have already designed and built components and bike frames. Additionally, I've always been the "hands-on" type, and I'm NOT getting ANY hands-on experience doing anything in grad school. This is another reason for my wanting to learn to weld. >Case(s) in point -> Does Joe Murray build all of the new Voodoos? > Does Joe B. build all of the Breezers? > Does K. B. build all of the Bontragers? True. But, at least, KB started out as a custom frame builder. All by himself. And look where it's gotten him. :) (not to say that the others didn't, I just don't know as much about them.) >|> *IF* this sounds like a good plan, is there any area of welding >|> technology I should concentrate on? The course description guide from my >|> local community college describes a variety of classes, and I'm a bit >|> lost on which one(s) to take. > >Which ones are offered? The current trend is towards TIG(GTAW) I think. > >TIG welding steel is pretty easy to pick up on, and is far more forgiving >than welding AL or Ti. Not that steel can't be complicated, but I think >its much easier. You might also want to know how to braze for doing >such things as braze ons, dropouts, etc. Once you get your two hands talking >to each other, TIG welding and brazing use many of the same motions. > >Don't waste your time with learing to stick weld(SAW), or wire weld(MIG/GMAW) >unless you feel some burning desire, or are preparing for a stint working >on a farm or an auto repair shop. > Right...this is what I thought, too. But it seems that the curriculum at the community college starts you out learning stick welding and GMAW. You have to take 3 or 4 classes before you have the prerequisites to take TIG. I guess there's really no way around that, though. Quoting from the course description guide: WLD101 Welding Fundamentals (3 credits/2 lecture & 2 lab hours) A course on theory and safety procedures. Students develop competency in the following shielded metal-arc welding procedures: stringer beads, butt welds, and T-joints in the flat and horizontal positions. Students become familiar with oxy-fuel flame cutting equipment and its application. WLD102 Advanced Welding (3 credits/2 lecture & 2 lab hours) Prerequisite: WLD101 A course on out-of-position shielded metal-arc welding with emphasis on proper heats, electrode selections, and AC/DC currents. Welding positions include horizontal, vertical, and overhead. WLD201 Preparation for Weld Certification (3 credits/2 lecture & 2 lab hours) Prerequisite: WLD 102 An advanced course in shielded metal-arc welding procedures to prepare for industrial certification. This includes weding single vee groove weld-butt joints with backing strips in the flat, horizontal, vertical and overhead positions following the AWS and ASME code specifications. and finally, the first TIG class: WLD202 MIG and TIG processes (3 credits/2 lecture & 2 lab hours) Prerequisite: WLD201 A course on the theory and application of gas metal-arc welding (GMAW), flux-cored are welding (FCAW), and gas tungsten arc welding (GTAW) processes. There's also other classes that doesn't seem to have any prerequisites: WLD103 Welding Safety and Applications (1 credit/1 class hour) This course is designed to give the student an overview of the oxy-fuel cutting, welding, braze welding, and the GMAW processes. Safety and theory will be explained, and hands-on welding techniques will be taught in the Welding Lab. WLD214 Welding Processes (3 credits/3 class hours) This course provides the student with a basic overview and understanding of welding processes. The course will cover procedures, principles, characteristics and equipmens associated with various welding processes. Students will become familiar with shielded metal arc, shielded arc, oxy-fuel, plasma arc, inspection, qualification, classification and safety. WLD221 Brazing and Welding (3 credits/2 lecture & 2 lab hours) A course for technical programs students. Covered are soldering and brazing of copper, steel, and aluminum tubing, cutting and welding of steel using oxyacetylene and electric are welding of plate and sheet metal. Which one(s) would you take? >Community colleges and tech colleges are excellent for filling in the >practical gaps left by the four(or 7 as the case may be;) ) year schools. >Extra- and Co-curricular(sp) activities such as the SAE design contests >are a groovy way to pick these skills up with only an investment in time. >I personally would be wary of any of my profs here using power tools. I was in SAE my freshman and sophomore years. No one really had the time to teach me anything. Only one guy (a senior) knew how to weld, and that was because he learned in high school. After he graduated and left, the group was hard-pressed to get any welding done. I think they ended up buying a $199 table-top MIG welder from Sears and ran it without the gas. Didn't make very pretty results. >While you are at, consider learning about how to work with other >machine tools. The vetical mill and lathe come to mind. A little >experience with these machines goes a long way. If you can talk >intelligently with the machinist working on your latest project, you >will avoid becoming the subject of breaktime tales. If you get good, >you can even forgo the machinist completely (if you have time). I can make crude things with a mill and lathe. I have some basic experience on these tools, as well as drill presses, grinders, cutoff & band saws, etc. I fabricated my engineering senior design project, which is how I got to use these machines. I wouldn't say that I'm any GOOD at using these, just that I can actually make stuff with them. But things like feed rates, cutter speeds, etc. are all a mystery to me. Thanks for the advice! Jim . . . . James Gourgoutis [http://www.pitt.edu/~skoop] Graduate School of Mechanical Engineering ~~ ,o University of Pittsburgh / Pittsburgh, PA ~~ -\<, "Why am I so late? Couldn't decide which bike to ride!" ~~ ( )/( ) From davsum@aol.com Fri Jul 14 14:03:33 EDT 1995 Article: 54292 of rec.bicycles.tech Path: newsfeed.pitt.edu!gatech!howland.reston.ans.net!news-e1a.megaweb.com!newstf01.news.aol.com!newsbf02.news.aol.com!not-for-mail From: davsum@aol.com (DavSum) Newsgroups: rec.bicycles.tech Subject: Re: I wanna learn how to weld...need advice Date: 14 Jul 1995 12:09:32 -0400 Organization: America Online, Inc. (1-800-827-6364) Lines: 22 Sender: root@newsbf02.news.aol.com Message-ID: <3u64rs@newsbf02.news.aol.com> References: <3u4e3k@nkosi.well.com> Reply-To: davsum@aol.com (DavSum) NNTP-Posting-Host: newsbf02.mail.aol.com skoop+@pitt.edu (James W Gourgoutis) wrote: >To further boost my chances in getting a job in this field, I'm thinking >about learning how to weld during the coming winter. I'm currently >gathering information from my local community college on course >availability, costs, etc. >Does this sound like a good idea? My rationale is that if I ever get to >a point in my life where I have the opportunity to build my own frame(s), >I want to learn how to weld. By the way the industry is going maybe it would be more benificial to learn how to work with carbon fiber or other composites. By the way my ME required learning to weld, cast machine, ect, but composites other than fiberglass were a new thing. Also try high school night classes for learning to weld. From my experience the give you more freedom to work on what you want. later, DDS From lapdog@crl.com Fri Mar 22 15:48:34 1996 Date: Tue, 22 Aug 1995 16:12:42 -0700 (PDT) From: Gary Helfrich To: jim gourgoutis Subject: Re: MIG vs. TIG--why??? On Tue, 22 Aug 1995, jim gourgoutis wrote: > Date: 22 Aug 1995 12:49:07 -0700, > you wrote: > > So it sounds to me like you're saying that our plans to get a cheap MIG > welder for bike hacking are in general not a good idea? Ack. My personal opinion is that cheap MIG welders are kinda useless for most anything. They do not have the power to weld heavy material, and they lack the control to do a good looking job on the thin stuff. The guns are so cheezy that you spend more time clearing jammed wire than you do welding. An interesting point of reference is that a commercial spool gun (just the gun, not the whole rig) is about $1200. If the cheap stuff worked, why buy the high end stuff. > Could you give me a ballpark figure on how much these things would cost? > I've heard over on rec.arts.metalworking that really cheap portable MIG > welders can be had for $300-400 new. Are portable TIG units in the same > price range? Small TIG machines like the Maxstar are about $2500. This is everything, torch, cables, pulse unit, gas bottle, etc. If your budget is $400., and you want to build bikes, get a professional oxyacetylene setup. Or another route is to get a used commercial TIG setup. You can get good equipment for about %500. if you shop carefuly. The old stuff is not very portable, and will require some rewiring of your shop. > Also, how difficult is it to learn? None of us have any prior welding > experience. We tried to take a class at the local community college, but > things fell through. So this was our next idea. How crazy is it? Its crazy if you are using crummy equipment. The catch-22 is that experienced welders can lay a bead with almost anything. Beginners need all the help they can get, and bad equipment may just make you throw up your hands in frustration. Shameless commercial plug warning!!! You could also take the UBI weekend welding seminar. It's only $300. and you get to use all the good stuff. If you can get ahold of some good equipment, its just like wanting to win the Grundig Cup. Lots of training will work wonders. Hope this helps Gary Helfrich From cmn1@can02.pge.com Fri Mar 22 15:48:50 1996 Date: Thu, 24 Aug 1995 08:13:39 UNDEFINED From: Chris Neary To: James W Gourgoutis Subject: Re: MIG vs. TIG--why??? In article <41d196@usenet.srv.cis.pitt.edu> skoop+@pitt.edu (James W Gourgoutis) writes: >From: skoop+@pitt.edu (James W Gourgoutis) >Subject: MIG vs. TIG--why??? >Date: 22 Aug 1995 16:40:06 GMT >I'm sure that this has been brought up before, but... >*Why* is TIG welding preferred over MIG welding for bike frames'n'such? >Myself and 2 friends are considering purchasing a small, portable MIG >welder to get our feet wet (i.e. learn how to weld), and eventually to >use on weekend bike projects, so I'm wondering...if you can't (or >shouldn't) weld bikes with MIG, then I guess we shouldn't even bother. >Is there even such a thing as a small, portable *TIG* welder? >As alway, any advice is appreciated. >Thanks, >Jim >. . . . >James Gourgoutis [http://www.pitt.edu/~skoop] >Graduate School of Mechanical Engineering ~~ ,o >University of Pittsburgh / Pittsburgh, PA ~~ -\<, > "Why am I so late? Couldn't decide which bike to ride!" ~~ ( )/( ) Assuming you're familiar with the mechanics of both processes, GTAW (TIG) is preferred since the amount of arc energy applied to the weld can be controlled independently from the amount of filler metal added, resulting in better control of weld penetration and puddle dimensions. There probably are bikes welded with GMAW (MIG), but they will be of lesser quality. Can you say Huffy? :-) Portable, inverter based GTAW machines are very common. We use Powcon brand machines, about 70 lbs and the size of a small suitcase. I don't know if anyone makes a light duty GTAW machine which compares to the small "suitcase" GMAW machines you find in auto body shops, though. If you want to pursue this, Lincoln, Miller, and Powcon would all be good venders to talk to. Cheers, Chris ======================================================================== Chris Neary Pacific Gas & Electric Company Welding & Inspection Services Group cmn1@pge.com "With reasonable men I will reason, with tyrants I will give no quarter" - Thomas Jefferson ========================================================================= From morgans@mindspring.com Fri Mar 22 15:49:30 1996 Date: Fri, 25 Aug 1995 22:38:36 -0400 From: Jim or Laura Behning To: James W Gourgoutis Subject: Re: MIG vs. TIG--why??? >Myself and 2 friends are considering purchasing a small, portable MIG >welder to get our feet wet (i.e. learn how to weld), and eventually to >use on weekend bike projects, so I'm wondering...if you can't (or >shouldn't) weld bikes with MIG, then I guess we shouldn't even bother. >Is there even such a thing as a small, portable *TIG* welder? I work at a science museum where a fellow is making a replica of the Wright Brothers first airplane. He chose 4130 chromoly tubing 1.5 x .035 inches. With a mig welder and .025 wire, I could run a bead 1/4 to 1/2 inch long before holes were blown in the tubing. Not ideal for a plane or a bike. I have a bike with 4130 tubing. I am am not sure of the wall thickness, but probably a similar thickness. I took a sample to a fellow to mig weld. In 2 minutes he did a beautiful weld that I would trust. This fellow makes sample defective welds for training purposes so he knows how to weld correctly. They use ultasound and x-ray for inspection. A cool process.The machine he used was a Miller that cost $5,000 used. An expensive machine just to play with. My suggestion is don't bother. My friend said the same thing to me. Tig seems to be suitable for thicker materials. From wgomes@earthlink.net Fri Mar 22 15:50:46 1996 Date: Fri, 25 Aug 95 16:29:44 -0700 From: Walter Gomes To: skoop+@pitt.edu Newsgroups: rec.bicycles.tech Subject: RE: MIG vs. TIG-why??? skoop+@pitt.edu (James W Gourgoutis) wrote: >I'm sure that this has been brought up before, but... > >*Why* is TIG welding preferred over MIG welding for bike frames'n'such? Hey Jim, The basic difference in tig vs. mig is control. With tig you get much better heat control, and a much finer bead than wire-feed (mig). Very good weldors (few and far between) can weld a joint so fine that its almost indestinguishable [without grinding](BTW a weldor is one who welds, not the machine). Using a tig torch is much akin to using a oxy/acetylene torch in that you control the heat (by varying the freq. with the foot pedal or thumb wheel) and control the amount of rod you add to the weld puddle. With a good tig machine its said you can (I can't) weld a razor blade to a boat anchor. The idea being to make a very hot spot over a very small area and control it. Tig is also the best way to weld aluminum and stainless steel (no, not to each other) On the other hand, mig has the current (heat) and wire speed (rate of rod added to the puddle) set at the machine. Again, a good weldor can use this effectively, but us mortals can make use of the better control to create a better weld. Mig is useful in coarse and/or production work (it's much faster than tig) If I were you (which I'm not) I'd try to score a ac/dc tig machine (or a ac/dc welder and an outboard high freq. aircooled torch). Don't get me wrong, Mig welders work well, and are probably easier for a beginner to use. But for a fine welding (eg. bicycle frames, etc.) a good tig has it beat hands down. You might check rec.crafts.metalworking seems I saw a post on how to build a tig using an automobile alternator (?) Hope this helps! Walter From josh@WOLFE.net Fri Mar 22 15:52:43 1996 Date: Wed, 6 Sep 1995 08:29:56 -0700 From: Joshua_Putnam To: skoop+@pitt.edu Newsgroups: rec.crafts.metalworking Subject: Re: MIG vs. brazing for bike frames In rec.crafts.metalworking you write: >We have only a small budget (~$500). Our initial plan was to purchase a >small portable 110V MIG welder (as has been discussed several times here), >but several people I have talked to via email (from other newsgroups) have >indicated that MIG welding will not work well on the thin wall chromoly and >mild steel tubes used in bike frames (0.9 mm, for >example). For this reason we have also begun considering getting an OA >brazing rig instead. I have also been given the impression that small, >portable TIG units are WAY out of our budget ($4500 ?) and are hard to >learn--is this true? I recently bought a new torch for brazing myself a new touring frame. After considerable discussion here and with experienced brazers, I decided I didn't need a full oxy-acetylene rig, but rather an air-acetylene torch using just a tank of acetylene and free air -- it looks a lot like a propane torch head, and costs half as much as oxyacetylene because there's one hose, one regulator, one tank, etc. Goss, Prestolite, and Harris were all recommended to me as good brands. >We don't really need/want something that will give us professional results. >We just want to be weekend bike hackers/framebuilders for fun and experience. Have you read Talbot's _Designing & Building Your Own Frameset_? It's an excellent book, and shows that you actually can braze a bicycle frame using nothing more than a MAPP-gas hand torch, under $45 at your local hardware store. I started doing frame brazing with one of these torches and it works quite well for smaller joints, but doesn't have quite enough heat to do large joints quickly. The fork on my current touring bike is one I built following Talbot's instructions and using just a hand torch. Talbot also has instructions for making one-off frame jigs from plywood, making fork jigs, hand-mitering tubing with files and sandpaper, etc. Definitely a hobbyist's guide, not a production frame builder's manual. I think this question is coming up often enough that I'm going to start compiling a FAQ contribution on it, including both book references (Talbot, Paterek, etc.) and sources for tubing, lugs, brazing materials suitable for frame work, etc. But first I have to finish my own frame, then write that project up and send it to Grant Petersen so he can decide if he wants it in the Riv Reader. My own frame is getting very near to being ready to braze: all the main tubes are mitered, the dropouts fit the chainstays, and the stays are cut to length. Now it's just the small stuff: getting the seatstays ready, mitering the brake and chainstay bridges, laying out the braze-ons (cable carriers & stops, bottle bosses, spare spoke carrier, Columbine quick-chainger, etc.), and clamping it all to the jig. With any luck I'll be brazing it by next week. -- Josh@WolfeNet.com is Joshua Putnam / P.O. Box 13220 / Burton, WA 98013 "My other bike is a car." From shampain@shampain.com Fri Mar 22 15:53:22 1996 Date: Wed, 6 Sep 1995 12:04:40 -0400 (EDT) From: Shon Shampain 301-949-0484 To: skoop+@pitt.edu Subject: framebuilding!!! [The following text is in the "ISO-8859-1" character set] [Your display is set for the "US-ASCII" character set] [Some characters may be displayed incorrectly] Jim: The difference in the methods with respect to bicycle frame building are the following: 1) MIG - no one uses MIG for a frame. I don't know all the reasons why, but when I researched it it was never really an option. 2) TIG - TIG is used extensively. The TIG unit I bought is a Lincoln Square Wave 255. To get this unit equipped and setup cost about $2,500 (US). I bought this unit when it was in beta test, so now they may cost more. The Miller Econo TIG is a less powerful and less versatile welder, but still costs about $1,500 (US). I believe that even buzz boxes can be set up for TIG relatively cheaply ($500 or so) but you would then lose such important flexibility as a footpedal or hi-freq starting. I use about 100 Amps on Aluminum tubing so steel would be a little less. This suggests you should verify the duty cycle so that you don't buy such an underpowered unit as to be sitting around all the time. For what you are trying to do, though, 3) brazing is the way to go. Under proper verbal instructions, a complete novice could probably braze up a bicycle on the first try. I would suggest that to do a commercial-level TIG job would need 10 years plus welding experience. Your mileage may vary. There is nothing particularly exotic about any bicycle tube joint, but when you consider the bottom bracket, which has 4 distinct joints very close together, things get dicey. The seat stays are a tight 45 degree joint that needs the tungsten pulled way out on the underside. A novice will not likely succeed in this operation. The range of hand motion that will produce an error in TIG might be on the order of 1/16'', but is virtually non-existant in brazing. Also, you didn't mention your metal cutting capabilities. TIG and the like work best when the gap between tubes are <= .030''. If you are planning to use hand files you had better set aside a lot of time. Lugs are nice because if you aren't going for perfection, you can just hack off the tube and stick it in the lug. Another nice point about brazing (alternately called silver soldering by some), is that you can probably get by with a MAPP/OXY setup that is commonly (and cheaply) available at Home Depot or the like. The advantages are that you can expand later, if you want to, but if you keep it occasional, the price is right. I would suggest you get the book called Designing and Building your own Frameset by Talbot. Many places carry it including Velo News Books (they have an 800 #). shon shampain shampain@shampain.com 301-949-0484 ------------------------------------------------------------------------ shampain engineering Custom 7005 Bicycle Frames (in the near future) [ 1 ] Prototype(s) on the road, and counting! (Gotta start somewhere) ------------------------------------------------------------------------ The correct answer is achieved only after all possible mistakes are made. From palama@barsotti.dm.unipi.it Fri Mar 22 15:53:46 1996 Date: Wed, 6 Sep 1995 18:48:58 +0200 From: Antonio Palama' To: James W Gourgoutis Newsgroups: rec.crafts.metalworking Subject: Re: MIG vs. brazing for bike frames In article <42kb9t@usenet.srv.cis.pitt.edu> you wrote: : Which should we choose: MIG or OA brazing (assuming that TIG is out of : our league)? I woud advice going for a brazing set, most of the minor add-ons of a bike frame are brazed so you are going to need a brazing set anyway. : Is fillet brazing easier to learn than MIG welding? Don't know, it is, in my opinion, more difficult than lug brazing. : Any other advice will be extremely appreciated! Don't forget that bike frame building is not just welding/brazing, tube cutting/mitring, lug adjusting to the frame angles, frame streightening, seat tube and head tube reaming, bottom braket reaming/tapping are the first items that come to my mind, are fairly difficult and/or require expensive gear; there are many more. Good luck Antonio. From josh@Happy-Man.com Fri Mar 22 15:54:48 1996 Date: Wed, 6 Sep 1995 09:54:11 -0700 (PDT) From: josh@Happy-Man.com To: jim gourgoutis Subject: Re: MIG vs. brazing for bike frames >HA! I *knew* it...SOMEONE from rec.bikes reads the metalworking group! >I figured as much. :) Several of us, I think. I've seen Eric House in r.c.m from time to time, and some of the metallurgically-educated bike people, too. >You brought up an interesting idea. I didn't know that you could braze >with just acetylene...though I suspected it, since I've seen people >braze/silver-solder pipes with just a hand torch (granted, slight >difference there). So, how much did your setup cost (if you don't mind >me asking)? Also, can you fillet braze with this (I'm really clueless here)? >The reason I aske is this: One of my friends wants to build a recumbent, >so he's not going to be able to use lugs since the angles are all different. >Also, I want to modify a rigid MTB frame into a full-suspension frame, so >*if* I braze this, I'll have to fillet-braze, too. I would assume fillet brazing would work with this torch, but I haven't done much fillet brazing. If you either want to spend $100+ or can find a copy to rent or borrow somewhere, look for Tim Paterek's 90-minute video covering the design & fillet-brazing of a chromoly mountain bike frame. It's available from United Bicycle Tool, the big bike tool wholesaler, so any bike shop should be able to order a copy. >> Have you read Talbot's _Designing & Building Your Own Frameset_? >> It's an excellent book, and shows that you actually can braze a >> bicycle frame using nothing more than a MAPP-gas hand torch, >> under $45 at your local hardware store. I started doing frame >No, I haven't yet read the book, but I think I'll plan on getting it. >I have heard of it before, actually. Thanks for the tip. Here's another tip: Talbot's book, Paterek's fillet brazing video, the Paterek frame building manual, silver and brass brazing rod, flux, lugs, bottom brackets, stainless dropouts, and fork crowns are all available from: Henry James Bicycles 704 Elvira Ave. Redondo Beach, CA 90277 310/540-1552 >I better get you your stems, huh? Sounds like your bike is progressing >nicely! :) It is, and it keeps looking better as I get more parts ready to go. -- Joshua_Putnam@happy-man.com Happy Man Corp. 206/463-9399 x102 4410 SW Pt. Robinson Rd., Vashon Island, WA 98070-7399 fax x108 From josh@Happy-Man.com Fri Mar 22 15:54:56 1996 Date: Wed, 6 Sep 1995 09:56:54 -0700 (PDT) From: josh@Happy-Man.com To: jim gourgoutis Subject: Re: MIG vs. brazing for bike frames Another good catalog: Cyclo-Pedia, Inc., P.O. Box 884, Adrian, MI 49221, has two catalogs that might be of interest, the Frame Building Catalog and the HPV Parts Catalog for recumbent stuff. Catalogs are $1 each. From sshampain@CDA.COM Fri Mar 22 15:56:53 1996 Date: Wed, 06 Sep 95 15:16:38 EST From: sshampain@CDA.COM To: skoop+@pitt.edu Subject: Re: framebuilding!!! (fwd) Thanks very much for the information. One question: If TIG requires gaps of around <= .030", what kind of gaps are best for fillet and/or lugged brazing? Jim: Let me dump off a bunch of information that may be useful in your decision. First let's define two types of gaps, a tube mitering gap is the amount of air between 2 tubes when they butt up against each other. A tube/lug gap is produced because a lug necessarily has to be larger than the tube (or it wouldn't fit!) - the amount that the lug is larger than the tube is the gap. Welding and fillet brazing are concerned only with tube mitering gaps, whereas brazing deals with both. The figure I mentioned of 030 comes from the Easton recommendations for welding up its 7005 Aluminum frams. You *could* fill a much larger gap, although the joint is weaker. The *best* situation is with virtually no gap. You might be able to get away with a larger gap with steel, and especially if you don't require a perfect joint. Fillet brazing, however, might be a different animal. You are not melting the two base tubes, so there is not as much 'play'. I would assume that you need to be very much closer, probably around 010. I will look this up for you tonight. Now, the tube mitering joint is less important in brazing lugs. This is because the strength of a lugged joint is via the connection between the tube and the lug via the silver (or whatever filler you use). When you buy a lug, it will probably be a bit tight, but via an abrasive close on the end of the tube, or the inside of the lug, you can get the 'proper' fit. Tighter is not necessarily better, each filler has a 'best' gap - this is because the filler is distributed by the flux via a capillary action that can only be optimally achieved with the correct gap. Again, I will look this gap up for you tonight as well. A custom framebuilder, even when using lugs, will probably miter the tubes exactly (probably < 030 tube mitering gap). You, however, probably don't have to. The tube inserts a number of inches into the lug. If you even (gasp) cut the tube off straight with a hacksaw and inserted it into the lug might be acceptable. I was even told that some Italian frame builders used this method when they were really busy - it was considered safe because the only way to find out was to hacksaw your bike - and who was going to do that? Brazing isn't used a whole lot in industry in general, but with one exception - plumbers! Copper plumbing pipe is commonly brazed, and in about 1/2 hour, watching a good plumber (or working with one) would probably be all you needed to know. The Talbot book is fairly good on this also. Good luck, shon shampain shampain@shampain.com (where's my .sig?) P.S. Ask any questions you have - when I was researching this stuff I found that info was hard to come by! Received: from cda1.cda.com by CDA.COM (SMTPLINK V2.10.04) ; Wed, 06 Sep 95 14:36:35 EST Return-Path: Received: from clark.net (shampain@clark.net [168.143.0.7]) by cda1.cda.com (8.6.9/8.6.9) with ESMTP id OAA20144 for ; Wed, 6 Sep 1995 14:45:06 -0400 Received: (shampain@localhost) by clark.net (8.6.12/8.6.5) id OAA02717 for sshampain@cda.com; Wed, 6 Sep 1995 14:36:28 -0400 From: Shon Shampain 301-949-0484 Message-Id: <199509061836.OAA02717@clark.net> Subject: Re: framebuilding!!! (fwd) To: sshampain@cda.com Date: Wed, 6 Sep 1995 14:36:26 -0400 (EDT) X-Mailer: ELM [version 2.4 PL24alpha3] MIME-Version: 1.0 Content-Type: text/plain; charset=ISO-8859-1 Content-Transfer-Encoding: 8bit Content-Length: 1359 From ope@u.washington.edu Fri Mar 22 15:58:02 1996 Date: Wed, 6 Sep 95 12:02:02 -0700 From: David Opincarne To: skoop+@pitt.edu Newsgroups: rec.crafts.metalworking Subject: Re: MIG vs. brazing for bike frames Hi Jim, I've never made any frames myself, but my brother and his freinds are/were hevily involved in manufacture and repair for awhile so I might be able to give you something to think about if nothing else. You didn't mention what kind of frames (road/off road) you were interested in. That will determine the kind of loads that will be placed on the bike. A weld is definatly going to stronger than a fillet braze, but for a road bike the dynamic loading isn't going to be as great so brazing would work. As I'm sure you're aware some very fine road bikes are made with fillet brazing. If your looking to make ATB frames then I think you need to look at either welding or lugged/brazed frames. I belive that lugs can be obtained through mail order. >From what I understand the real skill in fillet brazing is in grinding the tubes so they fit together properly. I belive this is usualy done with a camfer. On the whole though I (IMHO) belive brazing is easier to learn. If you think you might want to experiment with aluminum frames you'll need to consider welding. Custom frame manufactures are pretty common, so you might want to find one in your area and pick there brain. If someone at the local bike shop isn't repairing frames themselves then more than likley they can tell you who is. Good Luck -Dave From shampain@shampain_ppp.clark.net Fri Mar 22 15:58:31 1996 Date: Wed, 6 Sep 1995 17:03:21 -0400 (EDT) From: Shon Shampain To: jim gourgoutis Subject: Re: framebuilding!!! > Thanks very much for the information. One question: If TIG requires > gaps of around <= .030", what kind of gaps are best for fillet and/or > lugged brazing? Jim: For proper capillary action using a silver based rod (these are termed free-flowing, and melt at lower temps), you are looking for a gap of approximately .003-.005. Remember that although this is tight, using lugs, it is relatively easy to obtain. For a fillet, this might be tough. There is, however, a class of rod that have lower silver contents, or are brass based. These don't flow as freely, and have a higher melting temp. They will fill a larger gap. I'm not quite sure how much bigger, but I would assume .010 or .015 might be the max. This is probably the way to go for a fillet. BTW - a welding supply house might have the spec's on max fill. Good luck. shon shampain shampain@shampain.com 301-949-0484 ------------------------------------------------------------------------ shampain engineering Custom 7005 Bicycle Frames (in the near future) [ 1 ] Prototype(s) on the road, and counting! (Gotta start somewhere) ------------------------------------------------------------------------ The correct answer is achieved only after all possible mistakes are made. From ernieleim@aol.com Fri Mar 22 15:59:04 1996 Date: Wed, 6 Sep 1995 22:17:32 -0400 From: ernieleim@aol.com To: James W Gourgoutis Subject: Re: MIG vs. brazing for bike frames Brazing, Mig, or tig, for bike frames ? I own all three of the options you list ( yes stick is out of the question). Oxy-acet. is the best low-cost option. I would be leery of trying to use a baby mig to weld bike tubes since it is very easy to over heat the weld and burn through on such thin materiel. Tig is an option if you have about $1500 to spend on a Miller Econotig. They are great machines for small projects such as bike frames. I've had mine for a year and a half and wouldn't give it up for anything( well maybe a Cybertig) . Over all I feel you should either get to know someone who can let you play with the equipment before you buy it , or best of all enroll in welding classes at your local community college. Taking actual classes can also give you a much better idea of how welding works, which type of welding to use when , and what is good equipment. Good luck on your bike frames. @---------------------------------------------------------@ Ernie Leimkuhler Stagesmith Productions Custom Metal Fabrication * ABANA SCA AWS USITT IATSE local 15, 488 * Renton, WA *"For this was a time when men were REAL men, women were REAL women and small furry creatures from alpha centauri were REAL small furry creatures from alpha centauri." --- Douglas Adams * @---------------------------------------------------------@ From josh@WOLFENET.com Fri Mar 22 16:00:52 1996 Date: Mon, 23 Oct 1995 07:14:25 -0700 (PDT) From: Joshua_Putnam To: jim gourgoutis Subject: Re: Need help with torches. > Hello again. How's your frame coming? I'm emailing you because >I need some advice on purchasing a torch for bike brazing. A friend of >mine and I went out torch shopping over the weekend, and discovered that >there are 2 types of torches: those that have a "swirl" feature and >those that don't (pencil tip). The swirl feature supposedly causes the >torch flame to wrap around whatever pipe you are brazing, providing more >even heat. Do you have any advice on which type I should get for bike >brazing? Talbot's book says nothing about this...though it *looks* to me >(from the pictures) that the type of torch he's using is the simple >pencil type. I think Talbot's torch looks like a standard model. Goss, who made my torch, offer two types of tips, "feather flame" and "target." The "feather flame" is like a standard welding tip, just a long, tapered nozzle, while the "target" looks a lot like a propane torch, with a mixer in the end to make a more compact flame. I got the "target" because it looked like a more controllable flame, though the catalogs said either could braze light steel tubing. > My friend and I first went to a local welding supply store, and >they couldn't/didn't believe that we wanted to braze bike frames. They >insisted that the only way to make frames was TIG welding...and they >wanted to sell us a Miller Econotig (~$1500). I went out to the car and >got Talbot's book, and then they were like "oh, okay...but we wouldn't >recommend it". I don't know how much of it was what they actually >thought, or just an attempt to sell us on the Econotig. The first Lincoln supplier I called locally insisted that brazing anything with acetylene-air was simply impossible. I didn't bother trying to convince him otherwise since there were plenty more suppliers in the yellow pages. >Anyway, we >discovered that we could get an air/acetylene outfit from them for >approx. $200, while an oxy/acetylene would run around $325. We then went >to a Builder's Square, which had a cheap oxy/acet torch/regulator kit for >$187, along with the regular Benz-o-matic MAPP/propane & MAPP/oxy torch >kits, ranging from $30-$60. We've pretty much decided that we're going >to go the Benz-o-matic route. There was a nice MAPP/air kit with an >automatic piezo lighter for about $50 that was attractive. If we each >get one of these, then we'll be able to borrow each other's torch for the >big jobs requiring more heat (i.e., 2 torches, like you suggested). The piezo lighters are really handy -- that's what my MAPP torch uses, and it makes it much more convenient to save gas between joints since it's so quick to re-light. Have you looked at mail order? MSC Industrial Supply has a great catalog that includes a few pages of acetylene-air and MAPP-air equipment, and amazingly the 3000+ page catalog is free. (They might expect you to be a business, but they didn't ask me and I didn't tell them I was. They're at 1-800-645-7270 or http://www.industry.net/mrop/msc -- Josh@WolfeNet.com is Joshua Putnam / P.O. Box 13220 / Burton, WA 98013 "My other bike is a car." From buglbrnd@epix.net Fri Mar 22 16:02:53 1996 Date: Thu, 23 Nov 95 19:04:57 -0500 From: Buglehead To: skoop+@pitt.edu Subject: What filler rod to use for fillet brazing? "Low fuming bronze" is about the best for fillets. a good flux to use would be WELCO # 17 ( I have to check on the #, its been a while since I've bought it) I'll send you some if you want. -- Sincerely, David Luddy ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ AKA Buglehead buglbrnd@epix.net 717 265-2753 RFD #3 Box 102A "somewhere in the back Wyalusing, PA 18853 hills of Pennsylvania" From brace@loop.com Fri Mar 22 16:03:03 1996 Date: Sat, 25 Nov 1995 06:04:45 -0800 From: Chris Serrano , chris serrano Newsgroups: rec.bicycles.tech,rec.crafts.metalworking Subject: Re: What filler rod to use for fillet brazing? In article <48vifp$1eb@usenet.srv.cis.pitt.edu>, you wrote: >I want to do some fillet brazing on a bike frame in the near future. >What kind/type of filler rod should I use? If someone could give me % >composition of the components, that'd be great...or any other info. >I've spent the past month researching different types of silver wire, >only to find that I need to use brass wire for fillets. (I thought that I >just needed silver wire with a low silver content, but was recently told >that this is incorrect.) > According to my bike building book (and genereic sources) silver is stronger because it flows into fine joints better, but brass fills wide gaps. So the best work requires very fine fitting and silver. Brass is used on less well fitted parts to fill the gap. From wagamawe@ttown.apci.com Fri Mar 22 16:03:51 1996 Date: Thu, 7 Dec 1995 09:46:44 -0500 From: Bill Wagaman To: James W Gourgoutis Newsgroups: rec.bicycles.tech,rec.crafts.metalworking Subject: Re: What filler rod to use for fillet brazing? I would stay away from brass rod since it is a bear to work with. If you are building up a filet uses a brazing rod that is about 30% Ag, 32% Cu, and 32% Zn. If you are doing braze on work you want a higher Ag content rod, perhaps 50% or so. Use the same flux for both. Mr Bil In article <48vifp$1eb@usenet.srv.cis.pitt.edu> you wrote: : I want to do some fillet brazing on a bike frame in the near future. : What kind/type of filler rod should I use? If someone could give me % : composition of the components, that'd be great...or any other info. : I've spent the past month researching different types of silver wire, : only to find that I need to use brass wire for fillets. (I thought that I : just needed silver wire with a low silver content, but was recently told : that this is incorrect.) : Please respond via email. : Thanks! : -Jim : . . . . : James Gourgoutis [http://www.pitt.edu/~skoop](412.683.7654) From 102575.2433@compuserve.com Fri Mar 22 16:04:10 1996 Date: Thu, 08 Feb 1996 07:57:41 -0500 From: Richard Johnson <102575.2433@compuserve.com> To: James W Gourgoutis Subject: Re: Welding with propane? James W Gourgoutis wrote: > > In article <3110bd24.324080505@news.demon.co.uk>, > Andy Dingley wrote: > > >really oxidisng flame and so you're burning your way through the steel > > This is most likely a really basic question, but can somebody describe > the differences between an oxidizing, neutral, and reducing flame? I've > seen the terms alot recently, but haven't found any definitions. > > Thanks, > -Jim > . . . . > James Gourgoutis [http://www.pitt.edu/~skoop](412.683.7654) Oxidizing is when there is excess oxygen in the flame. On a hot piece of metal the oxygen combines with the metal and creates oxides on the suface (also known as scale). This is usually what you don't want. Neutral is when all the oxygen is being consumed in the flame. Theoretically you get no scale or anything but since you can never get an exactly neutral flame this is just an idea to shoot for. Reducing is when all the oxygen is being consumed plus the fire could use more. In this case oxides (scale) on the metal will actually go back to their component parts and you will reduce scale. This sounds good but in reality you often get other gases combining on you metal which are usually harmful to it. Usually people who cast and forge using any kind of flame will try for a just slightly reducing flame. This is especially true of forging where you get scale anytime you pull the metal out of the fire and subject it to air. Rick Rick From jdt@edsi.org Fri Mar 22 16:04:53 1996 Date: Wed, 06 Mar 96 22:34:58 cst From: John Thompson To: skoop+@PITT.EDU Subject: Re: Framebuilding with silver or brass? In <4hkc26@usenet.srv.cis.pitt.edu>, skoop+@pitt.edu (James W Gourgoutis) writes: >The rod I ended up using for this joint was Bernz-o-matic NS-3 or >something like that. It's supposedly a Nickel-Silver alloy, and is flux >coated (blue in color). The so-called "nickel-silver" alloys are much higher temperature than the silver you want for silver solder. "Nickel-silver" is great for filling large voids (like for dropouts), but it doesn't flow worth a darn. For frame joints you want something with a higher silver content (but no Cadmium) so it flows better. I use Harris Safety-Silv 1200 (56% silver content) with excellent results. It's expensive, but a well brazed joint will require *NO* clean-up beyond flux removal afterward. The blue flux you mention is generally indicative of a higher temperature rod. Silver fluxes are much more noxious than brass fluxes, too. >>It remains true that a silver brazed frame is much easier to repair >>than one done in brass. >Why? Is it due to the lower melting temps of silver, and/or its >increased 'runny-ness'? Exactly. The higher temperature and tenaciousness of brass braze makes it trickier to dis-assemble a brass brazed frame. If the frame has fancy cut-out lugs and such you can almost kiss it goodbye if it's been brass brazed. -John (jdt@edsi.org) From craig@hpcvusk.cv.hp.com Fri Mar 22 16:05:51 1996 Date: Wed, 6 Mar 96 13:13:08 -0800 From: Craig Durland To: skoop+@pitt.edu To: skoop+@pitt.edu (James W Gourgoutis) Subject: Re: Framebuilding with silver or brass? Newsgroups: rec.bicycles.tech Reply-To: craig@cv.hp.com X-Newsreader: TIN [version 1.2 PL2] In article <4hkc26@usenet.srv.cis.pitt.edu> you wrote: > The rod I ended up using for this joint was Bernz-o-matic NS-3 or > something like that. It's supposedly a Nickel-Silver alloy, and is > flux coated (blue in color). > Anyway, has anybody used this rod (or similar) before? Comments? It > was about $5-6 for a 3-rod pack. I built one frame with Nickel-Silver (5+ with brass) and found that Nickel-Silver is harder to form a fillet with than brass. Brass is easier to reflow to shape the fillet. I think Nickel-Silver is stronger than brass but it wasn't worth the extra effort. I also found that I had to use more heat than brass when trying to get a nice fillet. Also, more flux is better - it protects the steel when it is hot. I use Welco #17 paste and smear it just about everything that will get hot. Use the torch to move the filler around. Craig Durland craig@cv.hp.com From josh@WOLFENET.com Fri Mar 22 16:06:35 1996 Date: Fri, 15 Mar 1996 07:32:46 -0800 (PST) From: Joshua_Putnam To: jim gourgoutis Subject: Re: Framebuilding with silver or brass? I wrote: >Your questions about the nickel-silver rod got me thinking, so I >looked up brazing alloys in the on-line Thomas Register and found >lots of listings, so after work I'll be faxing off lots of >requests for product literature -- Bernzomatic, Englehard, Handy >& Harmon, All State, etc. I'll let you know if I get any really >good info on the nickel-silver, or if I see anything else really >interesting for bike work. Got a Harris Welco "Alloy Products Technical Guide" in last night's mail, and it actually has three nickel-silver alloys that have strengths 80ksi+. Welco 14 bare and 14FC are intended for poor-fit, high-strength joints, and are designed to allow rapid build-up of filler for replacement of broken gear teeth, worn keyways, etc. Tensile strength up to 85,000 psi, work hardens to 200 Brinell, excellent machining and frictional resistance. The problem for bikes? Solidus 1690F, liquidus 1715F. That's a little high even for 531, which has a top temperature recommendation of 950C, but if you use non-heat-treated CrMo like Reynolds 525, they say you can go as high as 1100C, so this would be a perfect rod for loose-fitting parts like dropouts, or perhaps for fillet brazing? Welco 17 bare and 17FC are thin-flowing nickel silver alloys used for smaller deposits with higher strengths, up to 95,000 psi. Suggested uses include drill bits, tubular steel, furniture, milling cutters, etc. Solidus 1690F, liquidus 1715F. Harris Welco 170 bare and 170FC are also stronger, up to 95,000 psi tensile strength, and are thin-flowing alloys used for butt-joints. They specifically recommend it for sweated joints on bicycle frames, but they must be thinking production frames, not high-quality, since the brazing temperature range is 1720-1800F. For this one they give AWS standards: AWS A5.8 and A5.27. -- Josh@WolfeNet.com is Joshua Putnam / P.O. Box 13220 / Burton, WA 98013 "My other bike is a car." From josh@WOLFENET.com Fri Mar 22 16:06:44 1996 Date: Fri, 15 Mar 1996 08:12:19 -0800 (PST) From: Joshua_Putnam To: jim gourgoutis Subject: More Harris-Welco info I can't remember if you were the one posting about fillet brazing with silver a month or two ago, wondering what alloys were used for low temperature fillet brazing. In any case, the Harris-Welco manual addresses this, too: they say Safety-Silv 38T (AWS BAg34) is a "low temperature, free-flowing alloy with exceptional fillet-forming quality." Solidus 1220F, liquidus 1325F. They also make Dynafast brazing pastes, powdered silver alloys pre-mixed in flux pastes. One in particular looks interesting to me, Dynafast N040, a paste that appears to be BAg4 suitable for joining stainless and carbon steels. It looks like all the common bicycle silver alloys are available in pastes, which come in one ounce syringes or larger jars. I may have to get some of this and try it out! -- Josh@WolfeNet.com is Joshua Putnam / P.O. Box 13220 / Burton, WA 98013 "My other bike is a car." From josh@WOLFENET.com Fri Mar 22 16:07:07 1996 Date: Fri, 15 Mar 1996 08:39:28 -0800 (PST) From: Joshua_Putnam To: jim gourgoutis Subject: Re: Framebuilding with silver or brass? >Um, the first few NS (or rather, NAg) filler rods you talk about above >sound similar to what I got from Bernzomatic...BUT, according to the >package, these rods have a range of something like 1200-1600 F (I really >don't remember right now), and a strength of 80kpsi. It seems that the >low temp range doesn't correspond with the strength. ALSO, from my color >observations, this stuff doesn't start to melt/flow until the steel is >almost orange...which according to Talbot, is up around 1600-1800 F (from >memory). Maybe I should take the package info with a grain of salt? >ALSO, it seems (and someone else mentioned) that this stuff doesn't allow >you to build up a fillet very well via multiple passes. I would definitely take the package with a grain of salt. The nickel silver I bought here from True Value definitely melts at a higher temperature than my plain low-fuming brass rod. I'm not sure it's as high as the Harris stuff, but it's also not as strong. >Did you see my recent post on rec.bikes.tech re: goggles? What do you >wear/use whilst brazing? I was (for fun) trying to melt a lugged joint >(top tube-seat tube) on my old practice frame, and ended up ripping the >top tube. I had previously removed the downtube, and I was applying >gentle torque to the top tube at the head tube end, in the hopes that as >the brass melted, the top tube would begin to rotate in the seat tube lug. >As I heated, I felt movement, but then noticed a big tear in the top tube >right at the lug. That's when I realized that I had heated the lug & tubing >up to a bright orange, rather than a bright red (as viewed thru my >goggles)...so now I'm worried that all my practice brazes have been at >temps that overheated the steel. Argh. I use dark brazing goggles, too, and they definitely do make it hard to judge the color of the metal. I occasionally pull them down to look directly at the metal to see its real color, but mostly I rely on the appearance of the flux and the filler. With silver it's easy, since the flux turns clear at 1100F and the filler melts just above that. With brass I look at the filler already in the joint -- if you look closely you can see when it goes from solid to liquid even if it doesn't move. If you want to be scientific about it, you can get temperature crayons that melt at specific temperatures -- draw on a part of the metal you don't need the brass to coat, and the crayon will tell you if you're exceeding the target temperature. >Last night, I made my first attempt at silver brazing, using 56% silver >filler. I brazed together 5 chrome chain sideplates, and then bent them >into a ring...so now I can say that I also make bike-related jewelry! :-) >It was hard to do, since the narrow section of each side plate heated up >first, before the 'holes', which is where I was trying to flow the filler. >I probably cold-soldered all the joints, but what the heck, it looks >cool! That's the one sort of joint where I use my hideously expensive oxy-MAPP torch -- the tiny flame is much more controllable for heating just where you want to heat. Many jewelers use a Smith torch that uses compressed air instead of oxygen. I haven't seen one in person but I'd be very interested to see what the largest brazing tip for them is -- if it's big enough to do a bottom bracket or crown, I may decide to dump my existing brazing torch. -- Josh@WolfeNet.com is Joshua Putnam / P.O. Box 13220 / Burton, WA 98013 "My other bike is a car." ++++++++++++++ FWIW, the measurement from the axle center to the center of the brake boss center is as follows: 26" wheels (MTB): 253.5+-1mm 700c wheels: 283.0 +-1mm 27" wheels: 286.0 +-1mm ++++++++++++++