Fireclay substitute

[azpizzanut]

Re: Fireclay substitute

Hello arosheger,

I don't know of a substitute for fire clay but there is a substitute for home made mortar. Check with a specialty insulation supplier for refractory mortar in bags. These are the guys that supply businesses with insulation products of all descriptions. I used Thermal Ceramics brand Smooth Set mortar. A 50lb bag might set you back $70. They may also stock bags of fire clay. You will need more than one bag for a 36" Pompeii unless you taper your bricks for a thin mortar joint. Most of the mortar gets used up from the huge joints on the outside of the oven. Another source for fire clay and refractory mortar would be one of the brick and masonry suppliers located in Bozeman.

BTW, Home Depot is loathe to special order a single bag or small amount of fire brick if it has to be shipped in. I've been through this on other items from HD. They would likely have to order a pallet of fire clay just to sell one bag. Shipping cost and shelf loss from torn bags make it unprofitable. The special order desk may be able to look up the nearest stocking HD.

Cheers,

[arosheger]

Re: Fireclay substitute

I finally found where to buy fireclay, but I will have to drive 2 hours away. Bottom line, there is no substitute for fireclay. Fireclay is as basic of a component as you can get.

[dmun]

Re: Fireclay substitute

The "traditional oven" link above states that any light colored clay is fire clay. I think this just isn't true. Half of Ontario is built with buff brick, I don't think anyone claims it's firebrick.

[Les]

Re: Fireclay substitute

Have you tried the places that do pottery in your area? A quick google showed a few. I was thinking of shipping it to you but the cost was $33.00 or $250+ for overnight.
You might be able to pull it out of the ground. Here is a dumbed down link about it.

Fire clay. Where to collect fireclay in nature and how. Buying fire clay.

Good luck.

[arosheger]

Re: Fireclay substitute

Does anybody have a recipe for making fireclay that can be used on a Pompeii Oven?

[arosheger]

Re: Fireclay substitute

So, I went to Home Depot, and they say that the Home Depot here in Montana does not carry fireclay and will not order it for me. I followed the link that Cheesesteak provided, and surely, as I entered my zip code, it responded by saying "[HC Muddox Mortar Clay is] Not available in your currently localized store".
I do want to mix my own mortar, that's why I am looking for fireclay. I will try to contact my local pottery suppliers and see what they have to say. But my original question is still, "What is a good substitute for fireclay?" in case I don't find it around here. Or are we all agreeing that it's either fireclay or nothing. My concern is not to be used for leveling anymore, but it is to create my own mortar.
Currently, I can only find wet, premixed fireplace mortar. Which the Pompeii Oven Instructions strongly suggest not to use.

PS Thank you all for your input, it's fun to read.

[Cheesesteak]

Re: Fireclay substitute

Upon further review . . . the HC Muddox "Mortar Clay" is, in fact, Fireclay.

See here: HC Muddox Mortar Clay

[Cheesesteak]

Re: Fireclay substitute

That bag says mortar clay NOT fireclay. In Australia bricklayers clay is wrongly labelled fireclay. it is not a refractory clay, but a product designed to make the mortar more "sticky". It still may be suitable buut is probably not a true fireclay, check with the manufacturer.

I hear you - here's HD's page - which calls it "Fireclay."

Home Depot Fireclay

and . . .

Here's Muddox's MSDS sheet for this "Mortar Clay." The MSDS indicates it goes by two different names (Lincoln Fireclay or Mortar Clay). This stuff is apparently made by Gladding McBean - which is just 45 minutes or so up the road from me. I pass their quarries all the time. Makes me think it's the same stuff that's all around me . . .

Muddox Fireclay MSDS Sheet

[dmun]

Re: Fireclay substitute

If your fireclay is just to mix with sand for your leveling medium, the cutting tray slurry will work fine. If you are going with the homebrew mortar, you're going to want fireclay. Your vendor saying they don't make it anymore is foolish. He just doesn't want to stock it (it's cheap). Try pottery suppliers.

[david s]

Re: Fireclay substitute

That bag says mortar clay NOT fireclay. In Australia bricklayers clay is wrongly labelled fireclay. it is not a refractory clay, but a product designed to make the mortar more "sticky". It still may be suitable buut is probably not a true fireclay, check with the manufacturer.

[Cheesesteak]

Re: Fireclay substitute

This, I believe, is the HC Muddox "fireclay" that HD carries:

[Les]

Re: Fireclay substitute

If you make your own mortar, the clay is required there as well. I just read on another thread where Home Depot carries fireclay. If your store doesn't carry it, maybe they can have it shipped there. And the people that tell you it isn't produced anymore are full of crap. There are bags and bags of it down the street from me.

[arosheger]

Re: Fireclay substitute

Thank you for your replies. As long as sand and brick dust are good enough to hold 1,000F (possible temp expected to be reached by a fire in a Pompeii Oven), I will use that idea. It's cheap and easy to implement.
This is the first time I am building an oven, am I going to encounter other places in the building project, where I will need to use fireclay such that the brick dust would not be enough? Reading through the plans, it does not look so. But for those who built their own oven, may have some insights of fireclay needs that the plans don't mention.

[david s]

Re: Fireclay substitute

I use fireclay as it that which is recommended, however at the relatively low temps we fire to I can't see why any powdered clay would not be suitable. If you have access to say powdered earthenware clay (ceramic/pottery suppliers) I'm sure it would suffice. Failing that you should be able to dig some clay from your own yard, usually below the topsoil layer, dry it, break it up and seive it. But that is a fair amount of processing which takes both time and effort.
Dave

[Les]

Re: Fireclay substitute

The fire clay under the floor is used to level it. You could probably get away with using sand. I would use the brick dust you are going to have from cutting the brick. Cut 50 of them in half and you will have more than enough to do the job (the 50 is a SWAG).