Doing some rust repairs on the beetle (rear guard mounting areas), & I want to know if I need to be quenching out my welds (MIG) with water as I go to control distortion. I used to do this back in the days when I only had OXY to work with.

I havent got good enough access to the back of the panel to allow me to get a dolly behind it to hammer on.

Any help appreciated.

Cheers
Brendan

Tack on tack is the best method. Using water will cause warping also. Just take it slow, and allow the metal to cool after half a dozen tacks or so, depending on the size of the area.

I use air to cool welds, as the water is too quick and hardens the weld too much. I metal finish most of my joins, so I use every advantage I can to make the job work.

Yep..blow with an air gun between welds..

Thanks gents, I think my problems were trying to get to much welded in one go & tacks too far apart. getting to much heat in. Will give the air a try.

Cheers
Brendan

Tack every cm, and then sand the tacks down to almost level with the surrounding panel.

Then do the welds 1 cm at a time with the air gun to cool. It takes about 20 seconds per cm, so you are looking at 3cm per minute.

I have done roof chops areas that have taken 6 hours just to weld the roof skin.

Thanks Pete, been tacking way too far apart. probably about 3cm. tried the air method the other day & definetely helped. I'm getting improvements as I go, so thanks to all. Will post up some pics of my progress shortly.

Cheers
Brendan