Used 1 50# bag of refractory clay and 1 bag of 60 concrete blocks (1 each) 4. 5 48″ angle iron5. 4 48″ threaded rod 6. 4×4 durock 7. 4×4 IsoBoard (expensive! 12/sf) (at Machine Project we used 16 1' pavers as we built this on a solid metal tabletop) 8. × 24″ Clay flue liner. Tools that came in .