I want to build a furnace to cast Inconel, which melts at ~ 1350 C.
I'm planning on using 1450 C as a target kiln maximum temperature, and 1550 C rated castable insulating refractory. Is this sensible?
I also need to be able to evacuate the furnace to a fairly high vacuum. I'm looking for a cylinder with a full-diameter removable, sealable lid, between8 1/2 and 14 inches in diameter, and 11 and 16 inches high, which will take a vacuum at perhaps 100 C - the insulation is on the inside, it doesn't get very hot. Any suggestions? Something cheap.
I thought of using a small milk churn, but they are aluminium and not entirely cylindrical, and the lid is smaller than the body.
A gas bottle could be used, but it would need a lot of work to make a removable, resealable lid (and I'm a bit unhappy about cutting one open anyway).
Any other suggestions? I have this image in my head of a (stainless?) steel container of about the right size, with a lid that clips on, a small drum perhaps, but I can't identify it.