I was thinking about forming aluminum and prepping joints for welding and it occurred to me that depending on the alloy its really easy to bring aluminum into position with a hammer. I recently fit an aluminum skin of tread plate to a waterproofed plywood seat box in a boat by making a few strategic cuts and going to town on it with a 3 pound machinist's hammer. It actually looks good. Well it looks good at a distance if you squint. LOL.
I have some projects I'm considering making from aluminum, and I was thinking that a hammer might be just the ticket for bringing some long edges into position as I welded out the assemblies. I've got a couple pieces of stainless flat bar and stainless angle I can use for welding backers, but it occurred to me a plane old steel hammer might just undo some of the work I did to prep the work before welding with.
Now I don't think I have ever heard of this before, and I'm pretty sure I've never seen one, but I bet I could make a stainless hammer and leave it in my welding box just for aluminum work out of some 1.5 inch round bar I already have on hand.
I wasn't actually thinking specifically about welding when the thought came to me. I was thinking about all the great fiberglass handle hammers I have that have a failing rubber over molding on the handle. I'm working on a solution for that too.