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

[fxpose]

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

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]

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

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]

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

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?