I have been making a few new tank bucks for a potential new bike. Not sure what shape I am after, so I just started chiseling. I usually use cedar, because it carves well but isn't so soft i cant hammer on it. I am going to try a super thick aluminum this time - dead soft 3/16th. Yes you can form material that thick, as long as you don't need to shrink it. One of my 1/8th thick aluminum tanks made it all the way across the country on Charles "The Nomad"s race bike, including a crash, without leaking. I do like overkill though.