Finally getting ready to go forward with this project.
Plan is to cut up a 22l (5.8 ugl) metal pail and line with two 25mm layers of superwool 607 HT, rigidize this and cover with a couple of layers of clay and zirconia mix. Satanite seems to be popular but not that easy to source here.
A castable refracotory hot-face would have been my first choice, but a bit to costly right now.
I will be melting aluminium with propane for a start and probably not that often so I should get plenty of use out this first furnace, and I can always patch cracks as they develop. So time to quit planning to build a furnace and actually build it….