How to bend sheet steel into a large cylinder

[mag1]

Got a question, How do you roll/bend a sheet of 16-20 gauge steel into a cylinder? I'm thinking about insulating a cylinder firebox, and wondering if this would be somewhat easy to do at home. What would be the best gauge to use for the outer skin also? .06" thick? or thicker?

thanks

[Gizmo]

I've used 20 ga. for outer skin a couple times and it works fine. Rolling a sheet around another cylinder tank of similar diameter is the only thing I can think of to do that job except to have a local shop run it through their roller. Keep in mind you will need about a foot of "flash" on both ends to give you something to grab it with so your finished piece will be curved to the very edge.