Fireclay + Spec Mix OK for Homebrew or NOT

[Dino_Pizza]

I am lucky enough to get to help my cousin build his 40 Pompeii and he's copying my build very close but got the following advice from 2 brickyards for making high heat mortar:

They said to just mix 1 part Fireclay with 2 parts "Spec Mix".

I'm trying to get get my cousin to make the real Home brew:
3 parts #60 silica sand
1 part Lime
1 part Portland
1 part Fireclay

But because 2 brick places told him the same thing, he feels that's the way to go. I'm wondering what the outcome might be using 1/3 fire clay in a bag of Spec Mix.

Any input is appreciated.

[Lburou]

Re: Fireclay + Spec Mix OK for Homebrew or NOT

So, Dino, what is in the 'Spec Mix?"

[Dino_Pizza]

Re: Fireclay + Spec Mix OK for Homebrew or NOT

Spec Mix a name brand that's popular on the West Coast. It has a reputation for being a "higher end, consistent blend" of ordinary concrete mix. It's spec sheet says "Portland Cement, hydrated Lime, dried masonry sand". That's it. I don't know what proportions but it's suppose to be ordinary cement, just a bit more consistent than slightly cheaper cement.

I don't work with cement much (to be avoided second only to plumbing ) and can't recall too much the difference in my "homebrew" mix on the dome and my cement mix for the base and blocks, but it seems to me, that ordinary cement might have some larger grains of sand in it. But then again, I've read on FB where others used 'play-sand' in the homebrew which is not as "fine" as optimal but still works.

I bet the proportions of ordinary cements 3 ingredients are not equal which whats normally called for in homebrew.

Any thoughts would be greatly appreciated. (PS: my cousin bought all his insulation board and blanket from FB and was about to buy their mortar but is going this rout instead. Oh well, I tried)

[Tscarborough]

Re: Fireclay + Spec Mix OK for Homebrew or NOT

There are many types of Spec-Mix, that is a brand name like Quickcrete. If you can find a "PCL Type N mortar" Spec-Mix, you are in the ball park to mix with fire clay for homebrew.

edit-The correct amount of fireclay would be approiximatly 16#s for an 80# bag of PCL Type N mortar.

[sseverance]

Re: Fireclay + Spec Mix OK for Homebrew or NOT

I know this is an old post, how did the Spec Mix mixed with fire clay work out? Has is held up over time? I'm on the West Coast and I was told by 2 different suppliers mix 3:1 and also 6:1 (Spec mix : fire clay). I'm thinking about going 3:1. I called Spec Mix directly but they wouldn't recommend anything for obvious reasons.

Thanks,

Steve