Firebrick

[polo1665]

Firebrick is extremely abrasive, would like to see this in action. Saw would be useless afterward unless this is some sort of brick I am not familiar with.

Soft firebrick is simply that, soft (porous). It can be cut with a wood saw, hacksaw, coping saw, even a thin file if you see fit. I have seen many ovens and preheats that utilize soft fire brick in their construction.
Hard firebrick is mainly utilized in hearth construction and has better wear characteristics than soft, but soft firebrick does have adequate insulating capabilities and would be perfectly acceptable for use in the walls of an oven, preheat, or fireplace.

K-23 Soft Insulating Fire Brick (IFB)

So yes, you must not be familiar with this type of brick

Mark

 

[RavensRoost]

I have found a place that will cast them, but pretty pricy at about $20 per brick including shipping. This is my Plan B, still looking for a low cost solution.

The bricks that are in there are "hard" and the broken ones are truly broken so patching with refractory cement is not going to be an option.

Looking online, when casting your own it looks like you have to fire them in a kiln for a couple of days, so that option is out.

I have also read online about cutting the soft-type firebricks with a carpenters saw, would not have guessed that.