Fuel tank fabrication issues

[MarkM]

Hi All!

After a long hiatus, I'm finally back!
I have a build log website started on EAA's website. I'll link to it here once I get it updated.

My top wings are finished and in the hangar, while my bottom wings and center section are in my workshop. With the bottom wings, I only have the wing walks and leading edge plywood to go. Not too many issues there, fortunately.

I'm also working on the center section. I decided to outsource the fuel tank to a professional, but even he is a bit stumped on the top skin. When trying to weld the .090 top skin to the rest of the tank, the welding distortion left the first effort looking like a large, very expensive metal potato chip.

I realize most people are going rogue when it comes to the tank, using rivets and pro-seal, or fiberglass, and just about anything other than the welding the tank per the Makelan plans. Most everyone who does have a stock to-the-plans tank were those fortunate enough to buy one from Makelan when Jeff was still in business. I know I'm grasping at straws here: have any of you here actually welded your tank per the plans? If not, does anyone have some insight as to just what secrets Jeff Shoemake had to get his tanks coming out so nicely? I've seen photos of the Makelan tanks, and it's clear to me that the weld bead does not penetrate completely through the skin.