View Full Version : old insulating castable recipe

Ed Pennebaker
08-15-2012, 11:42 AM
I've seen/heard many times recipes for low temperature insulating castable (sometimes referred to as Block Mix or 1900 degree insulating castable). I remember this being made from vermiculite, ball clay, and portland cement or similar ingredients. Haven't been able to find a real recipe. Anyone use this anymore or remember basic proportions/ingredients?

Pete VanderLaan
08-15-2012, 12:09 PM
We used a bag of vermiculite, three big shovelfuls of ball clay and a big shovelful of cement. Mix it on sheet plastic on the floor. Add water to taste and pick up the corners of the plastic to toss it around to mix. Trowel it hard on the item you are putting it on. It was a nice thing.

Dave Bross
08-15-2012, 08:47 PM
bag = one of those big 4 cu. ft. bags?

Cecil McKenzie
08-15-2012, 10:35 PM
Here is a thread from a pottery board. You might find some ideas here.http://www.alloyavenue.com/vb/showthread.php?5-DIY-Refractory-Compositions/page13

Pete VanderLaan
08-16-2012, 04:18 AM
bag = one of those big 4 cu. ft. bags?

Mix a small amount at first and see if you like the mix. It can be adjusted wildly. The clay makes it trowel easily and the cement hardens it.