I got kind of excited about that add on stoker. What kind of problems would that design have burning soft coal? That kind of device would work for me because it could be installed in the rear of my boiler and it pushes ash forward. My fire box is like 45" deep so I could retain grates in the front half for wood and hand firing and it would still dump ash into my ash tray. Converting my boiler to a true underfed looks like would create ash removal problems in the back. Berlin: what kind of design were you thinking of with fire brick and an auger for a poor mans stoker?