Kerr 666 Part 2: Refractory Brick Repair with Satanite

The door is looking good.















I made a replacement brick with a plaster of paris and silica flour ratio of 1:1 with 3:1 water sodium silicate ratio.   The now expected clumping, curdling, showed up.   I worked through that and added perlite in some unknown quantity.  By then I had lost control and just wanted to finish it.    The brick looked good the next morning but a day later it had self destructed.  This block was only exposed to ambient temperatures.

This is exactly as I found it.   Obviously there has been some expansion and it needs to be avoided.  I am mixing up very small test batches to determine what the problem is or the boundary line is terms of ratios.

EDIT:  it may also be a case of either the silica flour or the perlite sucking water away from the plaster causing it to not set or fail after setting.

I took one of the broken bricks from the side of the oven and encased it in satanite.  The form is covered with packing tape.

To be continued...