on mine my uncle just used 2 hammers like they do when forming metal on cars, place a sledge hammer on the inside of the drum at the lip and hit the outside of the lip up and in towards the sledge with the other hammer. That way you dont have to worry about sharp edges or uneven cutting. I will post pics on Friday when I get mine here.
Stoked UDS 2.0 and OTS
*Formerly known as Smokin Newbie*