This is a formula for making excellent refractory material to use to line the walls of a melting furnace. I am routinely melting aluminum and brass and I have been looking for a formula that is strong and lasts a long time. All of the formulas that I have seen that use Portland cement need replacing pretty often because Portland does not hold up under heat. Anyhow, I have finally found a formula that works pretty well. It's hard as rock and has good insulating qualities. You can make bricks or whole furnace linings with it. And.... You do not have to worry about a steam explosion if you don't cure it correctly. I have made shapes from this material and fired them while wet with no problems. If that were not enough: It's cheap! I am very excited about this and I want to share it.



Get it done:

This formula makes about 5 gallons of refractory. If you need more or less, just keep the proportions the same. It seems like the proportions do not need to be exact. Just get it close and you should be OK. If you experiment with it, I would be very interested in hearing about your results. That's the fun part AFAICT.

You need the following:

How to do it:

Other observations:

Where to get this stuff: