Once it gets hot I drop the metal lid on top and seal it with Dirt. Works ok but definitely not ideal
Discussion
I haven’t built one yet, but I like the designs that use the wood gas as a fuel to produce the heat for the process. Usually it takes the form of a drum inside a drum, like a 30 gal inside of a 55 gal. You can start it with wood or any fuel really, once the wood in the 30 gal starts off gassing stand back and smile. 😁
Do you happen to have links to plans, I’ve got barrels.