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Problem with tig welding stainless steel tubing

Posted: Wed Oct 18, 2017 2:26 pm
by oki270
Hello all,

newbie here so please be gentle :). I'm trying to make a balcony fence out of stainless steel 304 tubes (diameter 4 cm - 1.5", 1/16 wall ticknes / no backpurge / using 308 filler / around 45 Amps). The problem I have are angle joints (90 degrees) - as expected. Even though I don't overheat the tubes (at least I think so - no black areas) I still am unable to keep 90 degree angle whichever welding sequence I use. Keep in mind that I'm able to weld 1/4 of a tube in one shot. Please help how to get at least semi-decent angle after welding.

Edit; forgot to add - I always get an angle smaller than 90 degrees / I always make 4 tacks on all "4 sides"

Re: Problem with tig welding stainless steel tubing

Posted: Wed Oct 18, 2017 2:39 pm
by Oscar
It could be you're just simply not using an adequate welding sequence. If you elaborate on which ones you *have* used, then I'm sure soneone will be able to point out important considerations.

Re: Problem with tig welding stainless steel tubing

Posted: Wed Oct 18, 2017 2:58 pm
by Farmwelding
https://www.youtube.com/watch?v=chUOzYmxOH4

Jody starts on the outside edge and welds that. Maybe the video will help a little.

Re: Problem with tig welding stainless steel tubing

Posted: Wed Oct 18, 2017 3:15 pm
by oki270
Oscar wrote:It could be you're just simply not using an adequate welding sequence. If you elaborate on which ones you *have* used, then I'm sure soneone will be able to point out important considerations.
Last one I tried - 4 tacks - 90 degrees apart. After tacking still 90 degrees as required. After outside 180 degrees I still have 90 degrees between pipes. Then when I do inside 180 degrees, I pipe gets pulled inward so inside corner gets to cca 80 degrees :(. Any ideas?

I watched Jody's video on stainless square tubing and I do get pretty good corner on it but round one appears a bit more difficult and still cannot get it right :?

Re: Problem with tig welding stainless steel tubing

Posted: Wed Oct 18, 2017 3:25 pm
by 5th Street Fab
One cheat you can do is cut them slightly less of an angle so after welding it pulls itself to 90

When I use to do pie cuts we had them all laser cut I would sand the outside edge a little more then the inside when I was removing the dross.

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Re: Problem with tig welding stainless steel tubing

Posted: Thu Oct 19, 2017 12:00 pm
by dgapilot
Try welding 90 degrees, not 180. Let it cool between welds. Use some scrap to come up with the sequence with the least distortion, then adjust your fit up so when it shrinks, it stabilizes at 90 degrees


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Re: Problem with tig welding stainless steel tubing

Posted: Thu Oct 19, 2017 3:28 pm
by Farmwelding