has anyone tried lining the burn chamber with a same mix as used in a cast riser? i am thinking of trying this, but always worth asking before reinventing the wheel. i can see one problem maybe the floor might break up if the mix is too fragile. i have the basic RHM set up outside as per the design in the book. will be getting the 6 inch tube for moulding the riser from next week. as the CSA will drop from 49 sq ins to 36 sq ins i thought reducing the CSA of the burn chamber with the mix from the riser might be a good idea. i do have some insulative kiln bricks i could cut down and fix in place with clay slip as an alternative, but thought i might try the clay/perlite first.
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