So far all I've got is a disire to get into Blacksmithing, more towards knife making. I've done right much research and have and idea on how I want to build my forge. I was thinking about making my own firebricks. And building the form for them so they will interlock so I can dry fit them together so it's easier to replace the cracked ones. The firebrick recipe is 1 part by volume Perlite, 2 pt by vol Fireclay (refractory clay), 1 pt by vol Sand( Silica, pure as possible), 1 pt by vol Ash, 1 pt by vol Portland Cement.
I read that coal ash is the best type of ash to use to make firebricks. Has anyone tried to make their own bricks? Or does anyone have any suggestions? I appreciate any feedback.