Hello, I am almost done making a round mini forge out of fire bricks and satanite. The bricks are 2.5 inches thick and I have about 1/4'' of satanite lining it. But satanite does not give much structure, it is not like mortar. Could I use regular cement on the exterior of the bricks just to hold it together or will the heat travel that far and crack the cement or mortar. Thanks