I've got some practice under my belt and am feeling confident, and am having fun with aluminum. So it's time to start a FUN project.

I want to build a little Moon fuel tank out of aluminum. If it were steel, I'd know what to do. I HAVE NO IDEA WHAT TO GET IN ALUMINUM....

Little tank, say 8" in diameter, and 12-16" long or so.

What thickness of aluminum? What alloy?

I don't have anywhere locally to pick this material up, so I need to find it at eBay or say somebody like onlinemetals.com

Thanks for your help.
-Bob