Down at the "Regular Vise & Anvil" shop today, my original thought when fabbing these floor pan foot wells was that I would simply plug weld the stepped edge seen here. But things ain't all that exact and in order to have the wells appear even from beneath, as you can see, repositioning was needed on this one.
Start your clock, this is one hour in real time as of... now-
So I cut everything but the tacks there, ground those flush both sides, and ran the seam through the english wheel with an almost flat die to soften the bead rolled step and to even out the seam for welding. Next pic is after that and three passes of initial tacks with each pass between the last, using a Miller 212 MIG with .030 wire set on 5 heat and 45 wire speed. Gas gauge at 35 triggered. 18 gauge cold rolled mild steel here.
Its a floor, no planishing just stitching now. The nearby contours provide some resistance to radical warpage from heat. In between stitching passes, I began working one corner.
Any doubts about penetration? I do this a lot so I stay in practice but I'm not terribly ninja at welding so lets flip it-
That'll do, get out the rock-
That plus a surface conditioning disc gets me here. Ran out of time to 80 DA it then put a red scuff pad under the DA for a minute like I like to do. And which I did do inside the car. The 59 Catalina job car where I have been burning some serious calendar.