View Full Version : Managing heat warp while TIG welding 4130?

04-12-2006, 10:26 AM
Howdy All - I've just completed a TIG course at The Crucible in Oakland, awesome place, and now I've begun construction of a small chromoly frame (round tube) for my custom project. My first piece is a 1.5'x2.5' rectangle (roof), with 45-degree cut ends that line up pretty tight but I've got a couple 3/32" gaps to bridge. My welds look pretty enuf, but I'm getting more heat warping than I'd expected. Can anyone suggest a good method to minimize warping? I'm assuming clamping is bad cause it'll add more stress? Should I get back on the grinder till I have no gaps? How many times would you tack around a 1.5" tube? Thanks for your advice, I love this forum!


04-12-2006, 04:10 PM

I think your working on 1.5 X 2.5 tube. In my mind 3/32 gap is to much. First I would work on getting the best fit I could. It keeps the heat down. If I am welding a couple of peices together, Butt weld, and can then place them in my sturcture, I do clamp them down. I let them cool completely after welding, this does keep warpage down. I would do a lot of tacks. I like one about every inch. I try to look at the weld and connect my tacks in a way that will offset each other. IE, connect one on one side, then do a weld on the other side. Some times the is not possable, so I let it cool between welds.

Then again, sometimes all you can do is just beat it straight when your finished. I was welding up a motorcycle swing arm for a drag bike the other night. When it cooled it did not quite line up. So I ask the owner to step outside because I knew he did not want to see what I was going to do. I had to heat it up, put a couple of pipes in it and bend it back a bit.

Fit is everything when doing a butt weld. You can never have too many tacs.