Fire clay Mortar Vs Refractor Mortar FB.... HeatStop... Earthcore

[fxpose]

Originally Posted by Scott Welker

I used regular mortar, right off the shelf, and mixed in 20% fireclay. It was easy to work with, dried very hard, and is holding up well. I've had several firings where the oven got much hotter than I like, over 1000F, and no flaking, cracks, or any issues whatsoever have arisen with the mortar.

Not as cheap as mix-your-own but not expensive either, extremely simple and easy to work with. It was the best choice for me.

Scott

I like this approach as I already have a couple of bags of type s mortar from another project I'm working on and I can pick up a 50lb bag of fireclay for $8.

Does it matter the type of sand that's used in the type s mortar mix?

Thanks...

[david s]

I've been told that silica sand is preferable because it has sharper edges and corners therfore providing more grip for the materials to bond against. The silica is not a problem (melting) at the low temps we fire at. Not sure about its thermal expansion characteristics.

[130mountainside]

Both local Masonry Supply places I bought Fire clay from suggested a mix ratio of 1:1:1 Fire clay: sand: portland cement. A post above stated that they had no problems with a similar ratio. I hope I do not have issues as well. Question: what if cracking is excessive- what is the course of action- repoint with heat stop?