For those of you who rough turn and boil bowls to reduce cracking, what do you use as your heat source for large containers?

I have been using a propane burner and stand (from a turkey fryer) on top of which I place a large cast iron pot. I've looked at DIY rocket stove plans (for the intense heat, not because I need to be super efficient in my use of fuel wood), but haven't seen any that look like a good combination of easy-to-build, sized for a big boil, and no need to attend constantly to feed more wood.

Suggestions/plans welcome!
JN