2017- 36" pompeii oven construction in Sac California.

[jas0ny]

Here is what I got done so far. Hoping this is correct.

[Gulf]

Jas0ny,

I saw your pm late this evening, It looks like you got your answer on the open forum. It would be great if you posted pics of your steps toward completion of the oven.

A picture is worth a thousand words

. That way, we are all on the same page and may even see a consern that you are not questioning.

[jas0ny]

You are correct my dome is sitting on the ceramic fiber board

[JRPizza]

Jas0ny, to reiterate what David said, your dome bricks are not actually touching the hearth are they? They need to be insulated like the floor bricks are.

[jas0ny]

Ok and the second course of the dome bricks all sides should be mortared corrrect?

[david s]

No, unless yo're worried about their perfect level. Any floor brick replacement required (unlikely if you use firebricks) is likely to be in the centre, but removal of a floor brick with the dome mortared on top of it would be nigh on impossible. Since you are building your dome around the floorbricks the dome bricks shouldn't even be touching the floor. You should make sure though, that the dome bricks are sitting on insulation.

[jas0ny]

Good read thanks for the link. Ok since I am building around my cooking floor I'll put cardboard for expansion gap. Now do I need to mortar my dome brick to the floor?

[JRPizza]

No, you don't want to mortar your floor bricks, either between or underneath. If you build your dome on top of your floor you can put down a layer of news paper to keep the bricks from sticking (that is what I did after reading it on the forum). If you are building around your floor you should use cardboard or similar to maintain an expansion gap and keep mortar etc. from falling down into the gap during the build. I didn't taper my bricks (inside to outside) but did cut bevels so that I had very little mortar exposed to the fire, and then packed the gaps on the outside full. You can taper the bricks so that you have very little mortar inside to out, but it is way more work that bevel only. Lots of discussion on this in various threads. If you have not read the attached link you might want to go through it before you get much farther. Lots of builders saying what they would do differently if they were starting over. At least one says they would not have gone for such a tight fit on the bricks and just done the inner face bevel.

[jas0ny]

Today I'm am about to start the dome. When mortaring I do not mortar any cooking floor bricks correct?
Another question, am I mortaring all sides of the brick on the dome. There should be a small gap between bricks or the goal is too taper/bevel the bricks to have a tight fitting and to use less mortar?

[Gulf]

I know the pompeii plans mention to save the shavings when cutting the brick, would I use that material to mix in with the fireclay mortar? or just use it alone by itself?

Very fine screened firebrick dust from a wet saw can be used as a substitute for fireclay in home brew if fireclay can not be sourced. The coarser screened can be used to replace some of the fireclay in hombrew to guard against shrinkage in extra wide joints. The even larger cuttings can be added to the home brew for cladding to the exterior of the dome for more thermal mass. Since you have fireclay use it, or at least some in every batch as it will react better with the hydrated lime in the homebrew mortar.

What is the difference between the fireclay bag I have to the refractory mortar I have to use to paste the bricks on the dome?

I did a quick look at the thread and did not see what "refractory mortar" you have? Fireclay is not a refractory mortar until it is mixed with hydrated lime, sand and portland cement.

[jas0ny]

I know the pompeii plans mention to save the shavings when cutting the brick, would I use that material to mix in with the fireclay mortar? or just use it alone by itself? What is the difference between the fireclay bag I have to the refractory mortar I have to use to paste the bricks on the dome?

[jas0ny]

Got the FB board cut up.

[JRPizza]

Jas0ny, I would have answered sooner, but I didn't totally understand your question. I also wanted to keep my landing a brick and a half deep, and learned from the forum (thanks to Gulf and others) to move the chimney back over the top of the inner vent arch. Some build right on top of the inner arch, others (like what I copied) build an inner vent arch with a heat break and then build back over that arch. I'm posting one of my cad drawings that shows what I did. I had roughly a 7 inch opening in my vent arch, then opened it up mostly to the rear to give me an 8" depth. You can see it is very similar to what DavidS is showing above but done with bricks. Let us know if this helps.

[david s]

Here you go, like I said it's easier to cast it because you can make it thinner and do compound curves easily, but if in brick, something like this will work well.

[jas0ny]

heres another picture of what im taking about, I just need to know where the opening is going to be on my arch,