Welding/cutting sequence?

[Mike65 476]

I am getting close to the point of welding on the quarter skins on my 69 Coupe & had a question on which I should do first. I fitted the quarter skins to get the body lines to match the doors & the tail light extensions & temp screwd the replacement skin to what remains of the old quarter panel (see attached pic) & in the door opening at the "B" pillar & at the back by the tail light panel. Then I will cut through the new quarter skin & the old panel so I can but weld them together. Now should I cut it now before welding or weld it at the "B" pillar, the rocker panel & back at the tail light panel & then cut where I will be butt welding to the old quarter panel? Any suggestions or ideas?.

TIA, Mike.

[dzahm 10]

I would use screws for alignment, and then cut (assuming you are 100% sure its correct), remove screws, old qtr, replace new qtr, and begin the tacking process. I would not weld it prior to cutting. (your old qtr is probably keeping the new one 1/8 in out so minor adj maybe needed before final weld- not enough that you can't cut, but you just may need to tweak it very slightly prior to final welding)

[Midlife 814]

I've found that trying to cut two overlapping pieces of metal with a thin blade just doesn't work well, due to the width of the cut (kerf). The thinnest blade around is for the dremel, and even that can be too wide to be able to butt weld correctly.

 

I've found the best way is to cut the original metal first, then start cutting the new metal, leaving a good 1/8 to 1/4" extra. Then take a grinding wheel and grind down the extra metal until you get a good fit. Unfortunately, you have to work this several times, working on about 1/2-1" sections. Eventually, you will get a perfect fit. Then use welding magnets or clamps to keep everything aligned and start tack welding.

[BuckeyeDemon 211]

i think a small body saw blade is the perfect gap between sheet metal when butt welding.