K Fac-19

[carrieanddan]

Re: K Fac-19

I have decided to go with the K Fac-19. As a bonus it is cheap! less than vermiculite and concrete, and a lot less work.

When I went to the warehouse to look at things I found that they have mortar for firebrick, he apparently was a little confused as to what I was looking for.
I am still a little leery of getting my mortar from them, I don't know if it is a problem to have a mortar that is rated to 3000 degrees.... They build industrial ovens etc... I am worried that a 3000 degree mortar would have the same problems that a Heavy duty (high heat) firebrick would cause (not holding heat, but reflecting it all back making the oven too hot). Any thoughts?

[dmun]

Re: K Fac-19

I used two and a half inches of mineral wool board, insblock19, from Harbison Walker. I bought it from an ebay source, HW wanted almost as much as super-isol for the stuff. 19, btw, stands for 1900 degrees F., so it's not for as high temperatures as the stuff you found, but the outside of a wood fired oven is not likely to get much more than 1000. Insblock19 worked fine. Even a big long fire only warms the bottom of the support slab.

Super-isol is calcium-silicate or cal-sil. It's superior stuff, no question, but it may be a bit of overkill if you are not building a kiln or foundry furnace.

I'd be interested to know if a castable refractory would work as a firebrick mortar. Perhaps you can get a small bag from the vendor and do a test, before you commit. Heat stop is easy to mix and use, and that's a plus.

[carrieanddan]

Has anyone looked into this as a hearth insulation?
It is a mineral wool insulation block. I found this data sheet
http://www.dispro.com/upload/D1178.pdf
The rep at the local refractory supply mentioned it as a possible alternative to ceramic fiber board (which is what I am assuming SuperIsol is, I am having a bit of a tough time finding specs on it.)

For refractory cement he recommended Sparcast 30L, its a 3,000?F conventional castable that comes in 50# bags. It seems like overkill, but it is much cheeper than HeatStop from the fireplace supplier.

I am learning way more than I thought I needed to know about refractory products.

Thanks all for your input.

DAN