Weld Shrinkage

[Mike W]

You can find some info in textbooks. I have never had to be concerned very much with it except one time when I mig welded in a patch panel in a fairly flat auto body. When I has finished, the shrinkage made some waves in the surrounding metal.

Is there a general formula I can use to anticipate weld shrinkage. I'm mostly TIG welding mild steel and some Aluminum. I wondered if there are any charts or maybe a formula like a percentage of the material thickness that would give me a rough estimate. I'm not doing anything really fussy, but I just want to have a basic idea of what to expect.

Thanks,
Rich