Welding bike frames, how to get started?

mud2005

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Eugene, OR
Hello, I have been curious about welding bike frames and forks, but have never welded before. I am wondering what I need to get started? I see from ads bikes are tig welded, but thats about the limit of my knowledge. I used to be a glassblower so I have a torch, but I have a feeling nobody uses a torch anymore for welding. so I'm mostly wondering how much I will need to spend to get started and what I need to buy.
 
Welding machine (single phase for home use)
hood
means of getting argon bottles
gloves
jacket or at least denim shirt
tungsten electrodes
filler rods of various metals
electrical outlet installed at home that fits welder (240V USA)

For the welder, I suggest sticking with Miller or Lincoln machine (north of $2000 for tig) although some here have suggested that a cheaper model on ebay performed well enough ($600-$800). Here is a Miller on ebay that I cannot vouch for:
http://cgi.ebay.com/MILLER-DIVERSION-165-AC-DC-TIG-WELDER-COMPLETE-907005_W0QQitemZ390047995453QQcmdZViewItemQQptZBI_Welders?hash=item5ad0ac163d&_trksid=p3286.c0.m14&_trkparms=72%3A1205|66%3A2|65%3A12|39%3A1|240%3A1318|301%3A0|293%3A1|294%3A50

It seems to have some necessary accessories.

you also need some scrap metal for lots of practice!
 
Hi,

How about Carbon Fiber or Composite? It would be relatively easy to build battery storage into the frame.

http://www.sheldonbrown.com/rinard/carbon_fiber.htm
How I Made a Carbon Fiber Bike in My Garage
by Damon Rinar

http://www.sheldonbrown.com/rinard/howibuil.htm
How I Built a Composite Bike in my Garage
by Damon Rinar

http://blog.makezine.com/archive/2008/02/making_a_carbon_fiber_bik.html
Brano Meres created his own carbon fiber bike frame after being inspired by one made by Damon Rinard. He has some very interesting pictures of the whole process on his site. I particularly like the frame jig he created out of wood to hold the foam base material.

Everything began after I read the article "How I Made a Carbon Fiber Bike in My Garage" by Damon Rinard. Thanks to this excellent article, I decided to make a MTB frame, even though I've never dealt with carbon composites before (except carbon brakeboosters I made for my bike long ago). I always wanted to own this kind of frame.

md_bike1.jpg
 
Start with the book.http://www.timpaterek.com/
A good basic page about brazing a lugged frame.http://www.littlefishbicycles.com/frame/index.html

Most of my friends who've built frames used MIG welders. Welding under an inert gas shield makes clean up easier by reducing spatter.
You can get a 110V MIG set up that's adequate for bike tubing. They're around $500 plus the regulator, hose and gas bottle.
Cheaper ones are available but you want copper windings.
 
thanks for the excellent replies, so it looks like I am probably going to end up watching craigslist for a decent quality used tig welder for <$2000.
I can probably install a hood as the house I live has a chimney from a wood stove that is no longer used.

The idea of a carbon fiber frame is interesting, but I am a real fan of steel tubing. plus I may want to build a bmx frame first, and I have never seen a carbon bmx frame. Its probably to weak for bmx. I wonder if you can buy thicker carbon tubes? seems like if you could all the bmx racing bikes would already use them.

The Paterek book looks good, I'm getting a copy right now :mrgreen:
as far as mig welding, it's not the recommended weld for bikes from what I've read.
MIG doesn't work well on the relatively small diameter tubes that are found on bicycle frames. The puddle simply needs to move too fast for 99% of the welders out there to control as they keep their gun angle rotating around the tight radii. Another issue is that a MIG process typically has too high of a heat input for the thin wall tubes. As an example, a weld procedure here at work for MIG welding .050-.125" mild steel lists 80-120 amps and 15-19 volts. A general rule of thumb for TIG welding is 1 amp for each thousandths of material thickness.
 
I guess the reason they use MIG is that it's cheaper and easier to learn. The results are acceptable for the frankenbikes they like to build.
Aussie Jester used MIG for his trike project but he was also using large diameter tubing with thicker walls IIRC.
You've already got a torch so you could learn fillet brazing if you want a lugless frame
 
You've already got a torch so you could learn fillet brazing if you want a lugless frame

very interesting, I hadn't heard of fillet brazing. It sounds great from the little bit I just read about it http://www.gtgtandems.com/tech/brazing.html
I am definitely going to research fillet brazing some more, thanks for the tip :D I would love to dig out my old torch and put it to use

edit: I just realized that's a teapot on your head in that pic, haha
 
+1 on the brazing. Lotta good bikes are brazed.

Brazing includes the facility of joining dissimilar metals and other ES members have indicated that brazing can be very strong.

I learned how to oxy-fuel weld last year. It takes practice and patience to do well. (I weld poorly, for that reason.) It is not as fast as electric welding... but the zen of it is enjoyable.

If you can solder, you can prolly braze without much trouble.
 
I'd recommend finding a local community college/trade tech welding class. make sure they know you want to learn MIG. I "think" TIG is often used for aluminum, and is good to have under your belt. (or is it "heli-arc"?)

You can learn brazing by just buying the equipment and playing with it, It will come in handy on occasion, because not everything needs to be welded.

The instructor will have leads on equipment for sale when a past student wants to upgrade to something bigger/better.

You can also make good money part-time making custom turbo headers. Some guys are buying early 90's Civichatchbacks cheap (lightweight) and dropping in a K24 minivan engine to cheaply get more cubic inches. Some buy parts to attacha a turbo, but it is a custom piece. Prices are high, and lead times are long. If you bought one (or whatever is in demand at the time you're ready) you will have plenty of cash business by being a week faster and $10 cheaper.

Recumbent bikes (for old guys like me with money and bad backs) are rediculously expensive. Thats an opportunity to copy an existing recumbent or cut an existing frame up (to get the BB, head-tube, etc) and bend/cut/weld a new frame.

I bought a $200 WalMart mountain bike that has a front disc brake, and I'm making it a recumbent like Justins "cross-Canada" bike. Also, look at the prices of the Stoke-Monkey/Extra-cycle.

I also like how adding a rear suspension arm and shock (from a thrift store 24" MTB?) to a hard-tail makes a "long bike" that has plenty of room for a non-hub drive unit (plus large fold-out cargo panniers). Aluminum walkers at thrift stores are a good source for cheap pre-bent aluminum tubing.

Hydraulic shops and muffler shops can occasionally bend tubing for you until you make your own. The dies can be made from fine-grain, knot-free hardwood.

To round-cut the ends of pipes for a joint, you can start out by just using an angle-grinder. Later, if you only use 2 or 3 diameters of pipe, you can buy a few milling bits and make up a custom pipe jig with a bench grinder motor, or something similar.

Fig-201-Milling-Cutter-with-Spiral-Teeth.jpg
 
I have a couple of MIG welders, I would not bother with TIG not unless I was doing something special. You can get a Miller MIG welder pretty cheaply, maybe a couple of hundred. I used them for years and they are very reliable. I use inner shield, which is a flux core wire. Going this route makes the welder smaller and nice and portable. Gas would be nice, but it's quite a bit more expensive and you have to refill the cylinder.

Also get a helmet that has the instant darkening lens, it's worth the extra money.

Deron.
 
the guy I used as a mentor when i started recomended I start with stick welding, then move on to MIG. Stick welding is harder, but the skills you learn doing it are needed in MIG, and faster to learn on Stick.

The idea is you learn to pull an arc and lap your weld on stick because you have to or it just doesn't work. once you get the habbit of doing it, and learn to weld anything to anything at any angle on stick welding, you have the skill sets and the good habbits to weld MIG. The thing with MIG is it's easy to do it wrong and not know.

He also recomended I master MIG before going on to TIG. I've never bothered. I can weld bailing wire together with mig, . I might have to grind my welds out more, but its all I need.

Autodark helmets are nice for some. I've never found one fast enough, and always end up seeing a flash spot after using one. My eyes may just be more sensitive to light, though. I stack a #11 and a #5 filter when I weld. thats plenty dark enough to stare at the sun.
 
Hi,
spinningmagnets said:
Recumbent bikes (for old guys like me with money and bad backs) are ridiculously expensive. Thats an opportunity to copy an existing recumbent or cut an existing frame up (to get the BB, head-tube, etc) and bend/cut/weld a new frame.

I bought a $200 WalMart mountain bike that has a front disc brake, and I'm making it a recumbent like Justins "cross-Canada" bike. Also, look at the prices of the Stoke-Monkey/Extra-cycle.
Quite a few plans for DIY Recumbents and trikes here:
http://www.atomiczombie.com/

spinningmagnets said:
I also like how adding a rear suspension arm and shock (from a thrift store 24" MTB?) to a hard-tail makes a "long bike" that has plenty of room for a non-hub drive unit (plus large fold-out cargo panniers). Aluminum walkers at thrift stores are a good source for cheap pre-bent aluminum tubing.
Any examples or links?
 
Thanks for the atomiczombie link, Mitch. Here's the long-tail bike thread, they dont have to be ugly or goofy, its basically just taking 2 or 3 trash bikes and making something new:

viewtopic.php?f=1&t=9673&start=15

I don't like this particular frame, but this will give you the idea.

file.php


I took a basic stick-welding class many years ago and about a year ago I bought a good welder at a yard sale. I'm by no means an expert, but its fun and handy. I cant imagine not having one now. This thread has interested me in getting the equipment for brazing, that would be very handy too.
 
This thread is a nice coincidence - I just started modifying a frame today.

bikeandgas127s.jpg

I really don't understand why everyone is so keen on MIG. If you have to have an arc, TIG is so much better. TIG always used to be very expensive and I don't know how good the affordable systems are nowadays. But I like gas. And with gas you can also braze and silver solder.

Nick
 
Here's a thread about cheaply using Propane and Oxygen in a MAPP-gas torch to braze your own bike rames (Oxy-Acetylene torches have a different air/fuel mix, and acetylene is hotter than propane, but MUCH more expensive).

Anyone with brazing experience have any advice for "braze-newbies"?

http://www.bentrideronline.com/messageb ... php?t=8595
 
spinningmagnets said:
Here's a thread about cheaply using Propane and Oxygen in a MAPP-gas torch to braze your own fbike rames . . .
Anyone with brazing experience have any advice for "braze-newbies"?. .
Only that it would not be wise to eff around with jury rigged oxygen bottles.

The earliest home brew brazing set-up I saw was a compressor and motor from a commercial fridge and a propane bottle from the BBQ grill.

Or skip the compressor and torch altogether and learn to hearth braze right on the BBQ grill. (Not so good for lugless construction.)
 
I have been told by experienced fabricators that it is safe to use Propane/OXY in a MAPP/OXY gas torch. MAPP gas is mostly propane, with a few trace additives to make it burn hotter, so it cuts metal faster (I've been told).

I agree safety is important, and we should research any advice before doing anything with flammable/explosive gas (research anything I said, I admitted I havent done this yet)

I was told that using propane/oxy in an oxy/acetylene torch will work (much cheaper), but the air-fuel mix holes are the wrong size, and carbon monoxide may be produced, so don't use Propane/oxy in an oxy/acetylene torch.

Propane/oxy is safe in a MAPP/oxy torch (I've been told), just not as hot as acetylene/oxy. Hotter than the propane/ambient-air torch used for a plumbers copper pipe brazing. Take a metals joinery course, and verify everything with an experienced instuctor.
 
I was told that using propane/oxy in an oxy/acetylene torch will work (much cheaper), but the air-fuel mix holes are the wrong size, and carbon monoxide may be produced, so don't use Propane/oxy in an oxy/acetylene torch.

I was a glassblower many years back, and common practice was to buy a welding torch and replace the acetylene gas hose with one the can handle the propane. something to do with the propane degrading the hoses designed for acetylene. I used propane/oxygen in my torch for years, and it worked great.
but that was for glassblowing, maybe its not so good for brazing. I don't know what the effect of CO is when brazing.
I will probably rent an acetylene tank soon and try some brazing, it sounds like a lot of fun. Maybe my glassblowing skills will come in handy when brazing :|
 
Experience working with an open flame will be a benefit; moreso since you are familiar with oxygen blending. MAPP or acetylene-air may be hot enough for brazing bike frames, but OA is fast easy & cheap (big hammers have their benefits).

Welding requires more care in the mixture, since the gas alters the steel at those temps... brazing is much lower temperature and metals stay fairly unchanged.

Here's a link I just found: http://www.phred.org/~josh/build/build.html
 
I just talked to the welder at work, he occasionally brazes something, he likes using Oxy-Acetylene because its so much hotter that the brazing goes faster, and the piece doesnt get as hot. He says MAPP is hotter than propane, but...the cooler the flame, the longer it takes to heat up the piece, and the whole part may expand and warp out of alignment by the time you braze with propane.

He said cheap propane good for copper plumbing pipe. I noticed Home Depot carries a small MAPP/air torch to make copper pipe brazing faster than just propane/air. he said parts must be a tight fit, clean, sanded rough, and fluxed. He also said to heat the big side of the joint, and the silver-solder will "wick" towards the heat. He said he has brazed in a pinch with thin brass rod and thick copper wire (using O/A).

I have no personal experience with this yet...
 
I don't use propane for sweating copper, precisely for the reasons you state: low heat causes more of the piece to heat up and it makes crappy joints. Hit joints fast & hot with MAPP and you can join copper like a pro. (MAPP is dang hot, so if you're accustomed to propane it's easy to overheat the joint and fry the flux)

Bigger O/A tanks bring the cost of gas down significantly. For acetylene, I'd get nothing smaller then a 'B' tank (40cuft?). I find old b-tanks at fleas and sales for a couple of bucks... the gas shop will usually swap them for new tanks plus the cost of the fill.

I eventually got some huge commercial tanks on CL for about $300 (friggin heavy tho). The savings in the gas covers the cost of the tanks.
 
You can weld steel fine with an oxy-acetylene setup. Its slow so the heat effected zone is huge, but that might not matter depending on what you want to do. Brazing works good too with a gas setup.

Drunkskunk said:
I stack a #11 and a #5 filter when I weld.
I use a #14 to TIG and I thought that was extreme! I use a plain ole manual helmet also. If you're taking the time to build up something for yourself.. TIG or brazing is the way to go. Turns out purtyer. Production line stuff.. MIG is better of course.
 
I wish I would have learned how to weld in high school. I didn't learn anything in high school.
 
Interesting thread.. some good info, and some.. well.. not so good.

I've about 40 years with O/A (oxy-acetylene) before switching over to O/P (oxy/propane) about 7 years ago. I carry certs in TIG, MIG, stick and O/A, but prefer gas - especially for thin wall tubing.

TIG (or correctly called GTAW) is much like O/A only you use an electric arc and an inert shielding gas instead of a flame. A wonderful tool which welds or brazes a broad range of metals. It's slower and a bit more difficult to master than MIG or STICK because it requires good hand/eye coordination and a steady hand. A complete TIG setup is usually more expensive and the 'better' machines often requiring 240v.

MIG (or technically called GMAW) was originally developed for production work. It's the fastest of the group and usually easier to learn. But, it's somewhat limited and takes practice to weld thin stock, especially tubing. If your donor frame is, for example, .035" wall 4130 chromoly, then MIG won't be the torchman's first choice - TIG or gas rules here. On mild steel stock thicker than .045" it's handy and quick. It's also the cat's meow for one-handed tacking during builds.

GAS is the poor man's TIG and my hands-down favorite. If your plan is only one or two builds or an occasional repair, then spring for a budget MAPP torch. If your plans include multiple builds and you like to tinker and do a variety of other projects and repairs requiring a torch, then go with O/A or O/P setup. With the rising cost of bottle leases and refills, not mention the hastles of storage and tranporting, I now use a 20 pound BBQ bottle (propane) and an DevilBiss 505DS oxygen concentrator. My torch is a Victor J-28 w/alt fuel tips. I do both lug and fillet brazing using both LFB (Low Fuming Bronze) and silver. Here's one of my builds:

http://www.endless-sphere.com/forums/viewtopic.php?f=12&t=4532
 
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