posted 9 years ago
One method that works well is to use traditional wood stove door replacement "fiberglass rope" gasket, held in place with several layers of high temperature aluminum duct tape, and the band clamp over that. I found the fiberglass rope gasket at the local hardware store, but anyplace (home improvement centers) that sells wood stoves, fireplace inserts, and etc. should have it.
For the barrel and a half manifold system, and it depends on the barrels of course, but the ones I used joined together with a better fit by connecting the "lid flange" end of one barrel to the bottom rim end on the other barrel. And as it turned out, modification of the band-clamp was not required.