Lime for home made ref mortar

[carrieanddan]

I am looking to make my own Refractory mortar using the FB recipe (1,3,1,1).
I was assuming that the lime would be a powder, like portland cement, but all I can find is pellets? Is that what I am supposed to use?
I had a pail of Heat Stop, which was nice to work with but a bit pricey considering how dang much of it I will be using.

Alternatively my local refractory dealer (industrial firebrick) sells a refactory cement called Sparcast 30L which is a 3,000°f conventional castable cement. Seems like overkill to me for a pizza oven...


Thanks!
DAN

[gjbingham]

Lime comes in 80ish LB bags, and is indeed a powder. A bag-and-a-half should do the whole project. Check with your local masonry supply dealer, or check to see if there's a Mutual Materials close by. (mutualmaterials.com)

[Dutchoven]

It will most likely be referred to as "hydrated lime" and you will most likely only find it at a masonry dealer as some masons might have to mix a specialty mortar mix. I personally have never seen it at a home center.
Good luck!
Dutch

[Xabia Jim]

There are some other masonry places in town....Beldon Brick? comes to mind (just west of town on Leonard??) You could call around.

I bought lime once for agricultural purposes (keep the moss down) but don't remember where?? I wonder if that was the same stuff as your pellets???

I'd be curious what the differential in cost is to you between the home made mixture and the FB mix?

Jim

[carrieanddan]

I got my firebrick from Beldon, I will double check with them, but I do not remember them having lime... seems like it was on my list when I went there.

As far as cost, the RefMix from the FB store is $35 for 22 lbs (not bad) plus shipping $29.55 (oh my!) for a grand total of $2.93 / lb.

I can buy premixed 15 lb pals of HeatStop from Beldon Brick, if my memory serves me they were $20 so $3 /lb.

The 1,3,1,1 mix (without lime, because I have yet to find it) works out to $0.60 / lb. So unless lime is crazy expensive it should come in under $1 /lb.

[Dutchoven]

The lime should be between $8 and $12...I would guess...that is what it is around here...about 80 pounds I think...although it might be measured by the cubic foot....it is quite light stuff!
Dutch

[gjbingham]

XJim,
I'm thinking I spent about $50 to mix up all the mortar I needed for the oven. 2 bags of lime, two bags of fireclay, 3 bags of sand, 3 bags of portland cement. (The hospital visit after lifting all that was thousands though)

[Xabia Jim]

George, I didn't realize you'd gone with the homemade mortar mix. (that must have been when I was AWOL)

Anyway, how did that mix go? any regrets?

[carrieanddan]

Found it! Beldon did not have it, they sent me to a farm/feed store (after telling me that I didn't need lime and could just mix fireclay and portland cement... hmmm... don't think I will try.
In any case, I found powdered lime at the farm supply store it was $2.50 for a 50 lb bag, so that brings my grand total for the homemade mortar mix to a whopping $0.65 / lb.

I am still young(ish) and I have good insurance, not to mention all the friends who said they want to help... so hopefully there will be no hospital bills.

Thanks everyone for your input.

I keep meaning to get some photos of my oven up here, but have yet to spend the time figuring out how to do it.
If you are interested you can see some photos (although you will have to put up with other rantings and photos of things you don't care about) you can go to my website the dan & carrie show

DAN

[gjbingham]

Dan,
Glad we could help.

XJ - no regrets at all, but I've got a couple of decent cracks on the inside of the oven that I'm tempted to get in and fill with Refmix. I'm really indecisive on fixing cracks. In my mind, I envision them just busting open somewhere else after I closed their expansion joint.