As mentioned in Casting the Base, I added in the Inswool blanket around the refractory shell. At the very bottom, there’s not enough room for the full 1″ wrap, just .5″. Then 1″, then 2″ at the top. My last-minute decision to widen the crucible chamber for big pours has reduced total insulation value. Still, there’s a lot of insulating refractory even with NO extra inswool in the bottom couple of inches (about 1.5″ of highly insulated refractory + 1″ of inswool for the outer liner), so I’m ok, I’m sure.
After that, I added a refractory “cap” to stabilize everything and give a surface for the lid to sit on and provide a surface to seal against if I discover that I need to add a wool gasket to keep the flames from coming out the sides at the junction.
I needed a bit more work on the hinge mechanism to get it to hold the lid straight and allow the lid to fully descend. The angled reinforcing bar does wonders for rigidity. Here’s the end product (prior to painting the base.)
Here’s a picture of the lid moved to the side as if I were going in to retrieve the crucible. The top is large enough that the base can still support the lid while the hole is fully open, relieving me of hoping that the arm doesn’t deform over time, or generating a “stand” to hold the lid when it’s moved off to the side.
I’ve painted the base, and will be doing a firing tomorrow night to bake the paint and to drive out the water and solidify the refractory.
Then… well, inserting the burner, hooking it up to the propane tank and doing its virgin melt.