Depression Refractory Mix For The Backyard Foundry.
RecoverySoft / August 19, 2018

This old time foundry refractory mix for crucible or cupola furnaces was adopted by financially strapped foundry owners during the great depression, everyone suffered financial hardships during those days, so there was a lot of improvisation going on, now the backyard founder can save money making a home brew just like the old timers did. First off, you need to make up a mixture of grog, i.e. slag free old broken firebricks, break them up into 50%-pea size & 50 % Walnut size. Place the grog mix in a large bucket or drum, and fill the drum with water until the grog is well covered; leave to soak until there is no sign of air bubbles. Follow the next few steps carefully, as the amounts are made up by volume& not weight. Take “three volumes” of the now very wet 50/50-grog mix and add “two volumes” of good fire clay. (The measuring volumes can be made up of anything from a small tin to a large bucket, depending on the quantity you may need) Mix thoroughly and temper it like moulding sand with a water glass mix of 50% water glass & 50% water. Water glass is the old name…