Bending tube with a TIG torch

[jwmorris]

Tack the material to the bench, weld it and let it cool. Then cut the tacks and you are done.

 

[jwmorris]

FWIW, welding across the tube without structure, like the attachments that shielded arc posted, on the first page will cause more draw on the part than linear welding along the sides, not to mention makes for a weaker joint if flex is introduced.

It's a mistake a lot of welders make, a lot of times it pays more to know where NOT to weld than how to weld.

Box tubing is much more unforgiving than round in the given example.

 

[joshuabardwell]

This is what it's come to...

 

[Arc weld]

TIG might not be the best process for that judging by how much heat discoloration there is. TIG usually has nice neat small welds.

 

[joshuabardwell]

TIG might not be the best process for that judging by how much heat discoloration there is. TIG usually has nice neat small welds.

I'm just sitting here laughing to myself. It ain't the process, man, it's the weldor. I have a grand total of about three hours hood time behind a TIG torch. I have no idea what I'm doing, but boy am I having fun doing it!

:cool2::cool2::cool2:

Having just purchased a TIG machine, and also needing a cart for the gas cylinder, you don't seriously expect me to stick-weld the cart together while welding up coupons with the TIG torch, do you?

 

[joshuabardwell]

Amateur though I am, I do occasionally turn up a bead that I'm not totally ashamed to show my face around in public.



Do you think I'm putting too much heat into the metal?

 

[Shield Arc]

View attachment 321847

Do you think I'm putting too much heat into the metal?

It doesn't look like it to me. In my experience box tube is one of the most reactive to heat materials you can work with.

If you had an O&A torch you could have done this to bring the legs back plumb. The wedge on the left needs to be down at the base, your C-clamp was in the way to draw the heat zone in the proper place.

One time I got stuck building 199 of these Seattle Metro bus shelters! The legs had 1/16-inch tolerance for plumb. How do you think I kept that?

 

[CNC Dan]

This is what it's come to...

<img src="http://www.tractorbynet.com/forums/attachment.php?attachmentid=321846"/>

Don't feel too bad, I had to do the same thing. I was making a new bed for my pickup truck. I used 1.5" square tube. I had the frame done and everything was square and true. Now just skin it out with the sheet and it's perfect right? Warped the bajeezezes out of everything. Had to make some relief cuts to to get it back in shape.

 

[Arc weld]

Nothing wrong with your weld. Just TIG is a slower process so it puts more heat in.

 

[jwmorris]

Although TIG can be slower, something is most certainly wrong with your process for you to have warped the part as much as you did.

If your results were typical a TIG would be much less usefull.