newbie tig welding sheet steel

[lovelolamom]

Hi, I bought a 180 sd tig welder a couple of weeks ago and right now I'm trying to learn how to weld sheet metal patch panels for auto restoration. I'm trying to butt weld 18-20 ga. steel with a .5-1 mm gap. The problem I'm having is excessive heat (warpage) in the metal. The welder came with 3/32 tungsten so went down to 1/16 with .045 filler rod and that didn't help too much. Should I go smaller and work my way up? I can always go back to mig but I thought this would work better and give a cleaner appearance with less grinding. Am I wrong? I don't want to give up yet but I'm getting frustrated. Any suggestions, website help would be greatly appreciated. Thanks.

[Mike W]

Welcome, are you working on flat panels? Some hammer and dolly work may be needed if the weld is shrinking and making waves in the panel. I prefer tig over mig for bodywork. I just haven't had time to get back into it.

[burninbriar]

I'm new to tig also so take this with a grain of salt.
I would stay with the 1/16 tungsten and maybe sharpen the point a little more to give a narower bead.I have also been haveing good luck by keeping the gap to a minimum,none if possible on the real thin material.

[Sundown]

I would try about 20 amps, .040" electrode (Thoriarted or Lanthinated) with about a 20º taper and about .010-.015" flat on the end, .045" or 1/16" filler rod of ER70S-6, about 11-12 CFM, and no gap if I were going to tig it, of course I have a inverter so a transformer machine might be different. In reality I would use my HH140, .023 wire and mig it, esp. if I were going to grind it off anyway.

[lovelolamom]

It's extremely hard to make the patch panels perfect so as to butt them together and fuse without filler rod. I went down to the store today and bought .040 tungsten and .035 filler rod. Still not great results. It looks like I'm going to stay with mig welding. Tig welding seems to be good for welding tubing and thicker material for a nice appearance but it doesn't fit my needs in the auto body industry too well. To weld aluminum and stainless, couldn't I just add a spool gun to my millermatic 210 for the small amount of stainless and aluminum that I'll be doing? Which gasses are needed for aluminum and stainless? Thanks.

[Haystack]

Your setup will work fine. Tig is the way to go. In order to minimize warpage you have to introduce less heat. I use the same machine for patch panels. You need to tack, tack, tack. Put a tack in one corner, then move to the next corner and tack etc, etc. While the tacks are still warm you need to hammer and dolly them. You should tack until you only have about a quarter of an inch to fill in in between the tacks.

[fun4now]

the MM210 works great with the spool gun on aluminum, and SS will work fine without the spool gun :)

i would have to agree with Haystack on the TIG part.

bolth are verry doable some just prefer 1 over the other. myself i would rather be TIGing but only have MIG so it all gets MIG or O/A

you might try working a few patches on the work bench for a bit to get a good handle on it befor moving to the car.

[Paul Seaman]

lovelolamom:
Welcome:
I believe the trick is practice practice practice. Torch angle is paramount 75-90 degrees push the puddle and gas flow must be kept high enough to maintain coverage but not turbulance 20-25 cfh. Work small areas and jump around the work piece to avoid warpage, if necessary weld and stop for a while, you'll be better off than rushing.

Peace,