Home Brew

[llamabucket]

Yes! It will be separated from the fire bricks and exposed to the elements. So with this traditional mortar recipe, the only difference is just not adding fire clay?

I'm reading it may not be workable and to add something to it?

If it is for another layer of brick to add to the thermal layer, by all means. However, If that layer of brick is separated from the thermal layer by insulation and is subject to the elements, you may want to go with a more traditional mortar. The old formula for Type N masonry cement is 1 part hydrated lime and 1 part portland cement. Add 1 part of that mix to 3 parts sand and you have Type-N mortar. That formula works very well .

[Gulf]

Not exactly.

Type-N masonry cement is 1 part portland and 1 part hydrated lime. Add 1 part of that mix (after mixing the two) to 3 parts sand and you have Type-N masonry cement. So, the formula from scratch for type-N mortar is 1/2 part portland, 1/2 part hydrated lime and 3 parts sand.

Home brew refractory mortar is 1 part portland, 1 part hydrated lime, 1 part fireclay, and 3 parts sand.

[llamabucket]

Not exactly.

Type-N masonry cement is 1 part portland and 1 part hydrated lime. Add 1 part of that mix (after mixing the two) to 3 parts sand and you have Type-N masonry cement. So, the formula from scratch for type-N mortar is 1/2 part portland, 1/2 part hydrated lime and 3 parts sand.

Home brew refractory mortar is 1 part portland, 1 part hydrated lime, 1 part fireclay, and 3 parts sand.

Fantastic thank you!!! Another way to say it would be 1:1:6 of portland:lime:sand, yes?

Also, does my fire mortar withstand the elements just like the regular Type-N masonry cement? As I'll have areas where both types of mortar will be exposed. I assume it will but just checking

[Gulf]

Another way to say it would be 1:1:6 of portland:lime:sand, yes?

That is correct for type-N mortar.

does my fire mortar withstand the elements just like the regular Type-N masonry cement?

I don't have enough years of first hand experience with hombrew to answer that for sure. There are a lot of builds on this site that has the entry brick and it's home brew exposed. I haven't heard of any problems with the mortar not holding up. It is just that the home brew recipe is designed primarily as a refractory mortar. But, unless your oven is under some type of cover, you may want to think about a clear masonry sealer or an additive. That advice goes for any mortar recipe that you use for the exterior.

[Islandguy]

I have built 3 ovens over 3 years using the Home brew recipe as a castable over a sand form with a wire form cage 4" thick. That first oven is trailer mounted and has spent most of its life outside year round in the pacific northwest. It cracked during curing before it was ever fired and still has the same cracks with very little change since it was made and has been towed a couple thousand miles. The Home Brew formula is incredibly tough remember final strength is only achieved after firing the oven the home brew is not just a cement or mortar it is a fired clay it does not achieve full strength until you cook it out fully.

the original oven even after being soaked in the rain for weeks just takes a extra hour or bit more to steam out and come to heat. My experience does not lead me to think sealing is required.

1-1-1-3 is a Solid Mix.