I've about decided to build my latest furnace out of stacked fire brick held by an angle iron construction. I am building a Reil type Mongo burner and have plenty of propane. This will be almost exclusively intended for bronze work. My question is whether anyone has experience with coating the brickwork with ITC-100 for better heat reflection. I was also going to surround the brick with kaowool for added insulation then lock it all in with sheet metal cladding. I've worked a lot with 2600 insulboard and it heats quickly but has very little thermal mass.