What Concrete for a cast flue?

[fxpose]

I ordered mine, along with other related materials, from these guys. Shipping was free too.

Castable Refractory Cement - 25 lb.

[EricU]

Originally Posted by fxpose

I ordered mine, along with other related materials, from these guys. Shipping was free too.

Castable Refractory Cement - 25 lb.

Fxpose, thanks

Did you use the premixed style?
Is there an advantage/disadvantage to using either premixed or a dry mix?

[fxpose]

Originally Posted by EricU

Did you use the premixed style?
Is there an advantage/disadvantage to using either premixed or a dry mix?

I used the dry mix where you add water. That 25 lb pail comes in dry powder form. You just add water.

[EricU]

OK, since actually obtaining refractory cement is harder and more expensive (very), I have been thinking of two other ways to do my chimney liner;

1. Cut firebricks in half the long way and just build up my own while I am doing the exterior decorative chimney and fill the void with the pearlite concrete mix.
   
2. Use fire brick to make my transition then do the exterior decorative chimney, then use a sonotube liner or some kind of interior form and fill the void with the pearlite concrete mix

Any thoughts?

[david s]

Perlite cement mix against the hot side is not very strong or refractory solution 1would be better IMO.

[fxpose]

Originally Posted by EricU

Use fire brick to make my transition then do the exterior decorative chimney, then use a sonotube liner or some kind of interior form and fill the void with the pearlite concrete mix

Instead of using a sonotube how about using a single-walled stove pipe as interior form? I did that. I formed perlcrete around single-walled stove pipes from the vent up.

[david s]

George, that would be the simplest solution, but I think Eric wants a variation in diameter and has some bends to cope with.

[EricU]

Originally Posted by fxpose

Instead of using a sonotube how about using a single-walled stove pipe as interior form?...

I was wondering if it would be OK to do that. Just pour around it and leave it in.

Can I use the cheap snap together stove pipe stuff - 6" diameter?

Any suggestions on where to get it?

Eric.