Yet another busy afternoon; I mixed up some perlite/refractory and started building out a furnace for aluminum casting. Things are going pretty well so far. The 4:1 perlite to refractory mix seems to work OK, although I am sticking closer to 3:1 right now. My refractory cement already has some aggregate in it, so it’s a bit intolerant of the big chunks of perlite. I wish I could add some soap to the mix to make the perlite wet out better.
I also picked up a propane adaptor for a barbecue which just happens to match the size of a cheapass propane torch. This means I can use my cheap propane nozzle to heat the assembly. Turns out that there are standards for these kinds of things. Who knew!
Next up, drilling holes for handles in my cast iron skillet/crucible, then burnout for both the furnace and my 3d printed investment, then finally a test casting in Aluminum. Gonna be a busy week.