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anyone out there ever TIG weld frames?(12 posts)

anyone out there ever TIG weld frames?Largo
Jan 10, 2002 7:48 PM
Trying to get some 1st hand info on welding up your own frame.
re: anyone out there ever TIG weld frames?Bender
Jan 10, 2002 8:45 PM
I have done a fair amount of welding including oxy-aceteline, stick arc, MIG, and TIG. Although I have never attempted to TIG weld a bike frame the keys to becoming proficient in any type of welding are material preperation and practice. Material preperation involves fitting the parts to be welded and also cleaning, deburring, etc. This can get tricky when you're trying to shape round surfaces at compound angles. Frame builders use some specific tools for these steps.

The TIG welding part (after the joints are well fitted) will reguire a lot of practice. You have to form a bead on a round surface at compound angles while maintaining a steady rate of travel and adding the appropriate amount of filler rod. This is not impossible but it does take a fair amount of time to train you body and mind to make good welds. I'd highly recommend taking a TIG welding class or spending a lot of time practicing on scrap tubes of similar size.

This is the place to learnBlair
Jan 10, 2002 10:52 PM
This email list has some of the best small builders. Start by reading and searching the archives.

Sheldon Brown had a good starting project of making a tandem. There's plenty of other good stuff.

A few points to start with:
you won't save money over a massed prodeced bike.
you will end up with something different.
I hope you want to start by tigging steel. Aluminum is trickier with thinner walls, and must be annealed after welding.

Good luck

Tell us about your project
Jan 11, 2002 7:28 AM
Not to bust your chops or anything but aluminum tubes have thicker walls than steel tubes (generally speaking) and some tubesets (such as Columbus Altec) do not require any heat treatment. For the most part though aluminum does require heat treatment, and as a general rule of thumb, as the tubes get thinner, the heat treatment process become more involved.

The framebuilders list is a great resource. Many well respected builders including Richard Sachs, Brian Baylis, and Don Ferris (Anvil) post there from time to time.

Good luck.
Some cost infoNessism
Jan 11, 2002 7:54 AM
Dedaccia Zero 8 piece tubeset - $95-$105
Dedaccia ZeroUno - $65
Dedaccia EM2 Aluminum tubeset - $200
Dedaccia SC61.10A - $160

Add approximately $30 for brazeons and dropouts.

Of course these prices do not include consumables such as welding rod and such. Also, some tools are necessary or you will have to pay a local shop to do the taping and facing for you. The biggest trick seems to be figuring out how to heat treat the frame if using one of these high end aluminum tubesets.

The bottom line is that it is not all the expensive to put together your own frame if you have the know how.
Don't forget the cost of the tools...ohio
Jan 11, 2002 10:07 AM
-Jig: anywhere from $30 (plywood) to $1500 (henry james)
Plus other necessary tools aside from welder:
- drill press or mill
- hole saws, taps, reams in appropriate sizes
- table-mount grinder and grinding/buffing wheel
- compressor and airbrush, paint, appropriate solvents, appropriate disposal methods (unless there's a nearby paint/powdercoat place)

It adds up unless you already own or have access to the above, or plan on building frames for all your family and friends.
How about amperages for different materials?Largo
Jan 11, 2002 3:04 PM
Thanks for the info.
I've done a lot of SMAW and MIG, but never TIG.
How about getting rid of the HAZ after welding?
Can you heat it with a torch and let it cool at room temp?
Jan 11, 2002 4:38 PM
The HAZ is of no consequence. The butts on the tubes can withstand the loss of strength. It is a good idea to purge the insides of the tubes with an inert gas of some type - usually argon- to prevent contamination of the weld from the inside. Also, their are some new alloys that are more resistant to TIG heat. Columbus Thermacrom and Reynolds 853 come to mind.
Jan 11, 2002 4:56 PM
But don't you need to get rid of the brittleness that results from the welding process?
How about amp levels for different tube wall thickness/materials?
Jan 11, 2002 7:18 PM
I have to confess here somewhat, much of what I have stated regarding TIG welding is book learned and learned by reading the framebuilders email forum. I have TIG welded before but I'm not accomplished enough to attempt thin wall bicycling specific tubing. I have built several lugged frames, but I've never TIG'ed one together.

That said, my understanding is that brittleness created by TIG welding is not really a concern. The heat affected zone creates an annealed state where the material is made soft due to microscopic grain growth. This annealed area is ductile and not generally vulernable to brittle fracture failure. Of course, all this assumes a properly performed weld. Not some ham fisted attempt.
Jan 12, 2002 10:05 AM
Hey, thanks for the info, its all usefull.
Just trying to narrow down the amp range for frame building so i don't get a bigger machine than i need.
Now my shop will have a SMAW machine, a MIG, and a TIG.
2 buddies and i are going in on a TIG machine so we can make our own frames.
We'll start on steel, and see how that goes.
Considering that the TIG machine will be ~1500, and tubesets are ~100, that makes it pretty cost effective, even allowing for screwups. We'll practice on 4130 CrMo tubes, which are cheaper than tubsets at ~$4 a ft.
Just enrolled in a TIG course, because from what i've heard, TIG is a lot more complicated than good ol' ARC or MIG.
I've taken alot of Metallurgy in my engineering program, and have some very good instructors in the Aeronautical engineering dept. at the school, so i can pick their brains.
1st project is a single speed MTB.
Should be fun.
Jan 12, 2002 12:31 PM
Why not ask the framebuilders list what type of machine to get? Their is lots of talk about pulse inducers, AC vs. DC current, ect. This talk is all Greek to me but it sounds important. Good luck and email me if you need help with any general type of framebuilding questions.