Air temp and butt welding panels?

[AMXguy]

I'm  butt welding in a couple lower patch panels and I've done it before with good results , but if you had a choice should you have a cold shop shop so the sheet metal is cold or would you be better off with warmer steel when it comes to warpage? maybe it doesn't matter if you do it right I'm not sure.

[elitecustombody]

I'd prefer cold shop,but it won't make much difference, I usually use air blower after each spot to keep metal from warping