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View Full Version : MIG vs. TIG for auto restoration



CMcAllister
10-21-2008, 11:01 PM
Been sneaking around here for awhile, but now I would like some opinions. When repairing or replacing sheet metal panels like a floor or a quarter using a butt or a plug (spot) weld do you prefer to TIG or MIG? Do you get good results using a TIG to butt two panels together, using a silicon/bronze wire, without warping it up?

Supe
10-21-2008, 11:15 PM
You can do it with TIG if you have a lot of experience. For irregular gaps, very thin materials, tacks, etc, its hard to beat a MIG with an easy grind wire. For all practical reasons, I'd use MIG. The only time I've done TIG with sheet panels voluntarily was welding firewalls/floor panels when fabricating tube chassis for racecars, and that was because I wanted to use silicon bronze when welding to 4130 tubing.

hotrodder
10-23-2008, 10:01 AM
In the absence of a suitable spot welder then plug welding with MIG would be the best way to replicate spot welds. CuSi has it's uses, butt welding patch panels isn't one of them imo.

TIG and/or oxyfuel lets you minimise the amount of filler used and the joint can be panel beaten immediately to correct distortion. Distortion WILL occur when letting in patch panels, overlapping spot welds with MIG/using CuSi may result in a little less but the joint will need grinding down and there'll still be flaws to correct before prepping for paint. Taking all the work into account i get better results in slightly less time using TIG for the welding- hammer 'n dolly work being the key to good results. The area's that a MIG can save me time are ones that the rear of the panel cannot be reached- patching box sections for example

Didn't bother fully metal finishing this repair as the owner isn't doing a proper restoration and it's hidden under trim. Gives an idea of what's involved/the amount of distortion to expect when using TIG though... http://weldingweb.com/showthread.php?t=23036 (http://weldingweb.com/showthread.php?t=23036)

jamlit
10-23-2008, 06:52 PM
Ever watch Over-Haulin wit Chip Foose. They always use mig. I have been doing body panels for years and always used a mig.

rusty105
11-19-2008, 03:35 PM
Ever watch Over-Haulin wit Chip Foose. They always use mig. I have been doing body panels for years and always used a mig.



Oh I know this is a little old, BUT On "Muscle Cars" the fab guys use a lot of TIG. So I say to each his own. In some cases one is better, but I would guess most times one is just "different" then the other.

Rusty

lewray
11-19-2008, 04:56 PM
Use Mig