Cutting Fire Bricks

[kriso]

Has anyone ever cut a 230mm fire brick into 4 leaving 50mm, or should they be cut into 3 max (75mm). This is to cut costs down as the best I can get a single brick for is $6.50 thus if cut into 3 it is $2.16 each or if 4 $1.65 each.
Any suggestions on this
Cheers
Kriso
I can get clay pavers for $1.95 each but they are only 50mm high not 75mm

[mklingles]

You may need a sketch of the cuts your thinking of to get a good answer.

My thought is that the dome and floor require a certain mass of fire brick. Cutting them into smaller pieces doesn't seem like it would reduce the total number of bricks required. Maybe I'm miss-understanding your question.

[david s]

You could go for the cheaper pacers and back it up with a bit more cladding on the outside to get the thermal mass. That's what I'd do.
Dave

[kriso]

I was thinking of that dave and just add a little extra to the vermiculite layer. I may have some old second hand fire bricks on the way but they are pretty old, do you know what type of life span a fire brick has and if they will deteriorate when cut.
Cheers
Kriso

[david s]

Old second hand fire bricks should be quite ok, if they are really high duty bricks they may be harder to cut.

[GianniFocaccia]

Kriso,

Even if they are old, I think your used firebricks will be fine. If you want to add thermal mass, you can add a couple inches of refractory mortar to the outside of your dome. Adding thickness of vermiculite is adding insulation.