Battery Box Floor Replacement T-6C

[Mark Sabbann]

I have taken the first steps towards replacing the battery box floor in my red 'C' coupe, cleaning up the crud to see what condition the sheet metal is in. I found brazed-in sheet metal patches over both ends but solid original metal in the tow loop area. On the recommendation of Doug McDonnell, I will plan to replace the whole floor and hope to re-use the tow loop. I plan to do all the prep and fitting of the floor piece and hire my neighbor who is an excellent metal man and welder. He and his wife have done award-winning Beetle restorations like the brown '49.
After searching the forum on this subject, a few questions remain.

Once the original spot welds have been cut out and the new metal welded in but not spot-welded, are the outside bottom edges left as not welded and just primed and undercoated?
Or should those edges be continuously welded?

Regarding the tow loop, is it better to install it before or after the floor goes in?

What size of a spot weld cutter is best to use? Any other info I should know?

[Doug McDonnell]

Tom Perrazo's link should help you: viewtopic.php?f=4&t=20893&start=60 I don't have Ron Roland's book but he probably discusses this also.

[Mark Sabbann]

Thanks Doug, I read that thread but overlooked the photo showing 'spot' welds on the bottom, not a continuous weld.

[Martin Benade]

I used a regular drill bit, a little smaller than 1/4". I drilled through each weld either to plug weld from the top, or if the part I was saving was on the bottom I only went through the other layer and.separated the parts with a small sharp chisel. Then drilled the new part for plug welds. These cars had very many closely-spaced welds, far more than other cars new or old. I did not find a spot weld drill or cutter to be helpful..

[Mark Sabbann]

Thanks Martin, that's kind of how I imagined it being done before I learned about spot weld cutters. I can see the benefit of a cutter in possible speed of operation but at the same time it seems like it would take out more metal than necessary, especially with original spot welds that may be close together. I think it will take some trial and error plus I have to deal with a layer of brazed-in metal in some areas.