42” Pompeii in San Felipe, MX

[modified9v]

Thanks for the feedback Utah... my thought on the 1/3 vs 1/2 was the mortar joints being so close... they don’t line up but they are close. Is that OK??? I’m all about less work.

On the out-of-level slab, yes concrete and the Calsil will go on top. Curious, when you guy talk about fire clay, can that be substituted with the brick dust after it’s dried out?

Thanks, Mikie V.

[Karangi Dude]

Hi Mikie V.

The problem with laying the first course as a soldier course is the vertical joins of the second course will fall in several places on a joins of the soldier course to avoid this lay the first course as a stretcher (on their flats) by doing this you will be able to lay several courses before the odd join will start to line up with the joins below

Cheers Doug

[modified9v]

Thanks Doug... I originally wanted to lay that 1st course as a stretcher but when using 1/2 bricks the gap between the floor and that course is really big in spots. Maybe if I make each brick a wedge then the face would be small enough to reduce that gap where it wouldn’t be so large. I know we need some gap for expansion, but with the 1/2 brick we are talking about a small canyon of a gap. Thoughts?

[Karangi Dude]

Mikie V,

That gap will only get filled with ash and you won't know it is there once you start turning out some beautiful pizzas, there are plenty of ovens built this way, even a 1/4'' is not to big

Mikie, making sure that you don't have joins that line up from course to course is most important as this is where most ovens will crack keeping the joins staggered with as much overlap as possible

Cheers Doug

[modified9v]

Thanks again... would it be ok to take small wedge cuts off the sides to reduce mortar gap?

Mikie V.

[UtahBeehiver]

Good to see Doug chime in. For sematic purposes, I have attached a diagram of what brick orientations are (so we are all taking the same thing). So IMHO we are talking about using 1/2 headers instead of stretches, back to the original question, 1/2 soldiers have some advantages and disadvantages, pros, there is not a joint at the floor and dome for a peel to slide into, cons, due to the number of vertical joints, it will be harder to do stagger bond on the first course. Either case, you need to make sure the dome course also sits on the AiSi board and not the concrete hearth.As far as dome work, use the best faced bricks on the back half, making adjustments on the front half. Once the dome is done, only the back half is really visible. Mortar gap?? are you talking the backside? IMHO not worth the effort to reduce the back side gap (even though I did this with lots of time and effort) let mortar be you friend. Also, you should have about 1/6 to an 1/8" gap around the perimeter of the floor for expansion, no mortar, fills in with ash later anyway.

[modified9v]

Utah, I don’t see an attachment but I think I’m getting what you are saying. All brick will be on the FB board except the outer arch. In talking about the mortar gaps on the backside of the dome... well, attached is a pic for reference. I do see now that as the second course goes up it will kinda hide the big gaps under them on the first course.

Just seems like a lot of mortar to me. My thinking is that the mass of the brick holds heat better than a ton of mortar. Also, from my reading on various builds, the Portland is the weak link... just thinking that would be why the bricks would be better wedge cut, both top and bottom.

[UtahBeehiver]

Up to you, but mortar is just fine on the back side.The inherent nature of the Pompeii shape is self supporting for the most part. Mortar fills in the gaps. That said, home brew 3:1:1:1 (sand, lime, portland and fire clay) is cheap. It might be a different story if you are using an expensive commercial mortar such as Heatstop 50 (btw max. recommended joint size is 1/2" according to their literature, but I have seen a lot of builds going a lot wider). You are really after tight inside joints as pictured in you last post.

PS brick dust has been used in lieu of fire clay but you probably won't have enough just from you cuttings. Fire clay is available at any mason or brick supplier. HC Muddox is one brand prevalent in Calf.

[modified9v]

Right on... that is the way I will proceed. About that Homebrew... did a search but dagnabitt.. there is a ton of info. Can you tell me if it is a special kind of sand. I mean I live in the desert and could sift a dozen shovel fulls... unless of course it’s special sand.

[modified9v]

OK... so I figured out the sand... I’ll go buy some good stuff that works based on the thread on Homebrew.... Now, this has bothered me since before I started... how deep and how long is that first brick of the inner arch suppose to be? In the picture, the arch is not not nearly correct. The mock up of the dome to the left is correct as is the “fake” mocked up dome in front of the opening. Maybe I’m being too crazy about this... I just want to make sure that I have enough brick exposure from the inner arch to tie into the flue and outer arch... not sure this pic helps... I do know that it is driving me crazy... This is all for placement of the inner arch brick that will tie into the dome and not contact the floor... I’m dizzy.

[UtahBeehiver]

What type of inner arch are you doing? Highly recommended a tapered inner arch. There are dozens of examples on the forum and the IT is the key to getting everything right. It makes the dome to arch tie-in much easier. The longest brick on tapered inner arch is top dead center (TDC). A tapered inner arch is a difficult concept to understand so I attached a couple pics to help. The first is how the IT helps with dimensions and angle, it is on a partial arch but it works the same of a full arch (compliments of Mr. Chipster), second is how the bricks look . Not all the bricks are the same they change as they move left or right of TDC, so you cannot cut all at one or take a left side and place on the right side.

[modified9v]

Thank you Utah for the response. Sorry it took so long to respond. We just got back to San Felipe with the mortar supplies and I was able to pick up my FB board from my PO Box.

I love that first picture... not sure when I first saw it... I know it’s been posted many times and it really is helpful. My struggle is with the brick on the very bottom. I’m not sure how far it needs to stick out from the floor.... you know, where it will make up the reveal and the contact with the door. Maybe 2” inches? I’d like to to be out as far as possible but still come up with enough brick at TDC to complete the transition. My reasoning for this is to help make my heat break joint and subsequent flue work out seamlessly. (Man, I’m not sure I understand what I just wrote).

Today I hope to get the arch form built. Still undecided as to a full arch or partial. I better figure it out pretty quick. LOL

Again, thank you...
Mikie V.

[UtahBeehiver]

I am not sure what you are asking, maybe be a little sketch or something.

[modified9v]

Maybe this helps and maybe I’m over thinking it all. In the picture, the brick that has the two arrows on it... I’m trying to find the proper orientation of the brick that will be below it so there will be enough brick to cut as the dome goes higher. If the arch is moved out, away from the oven too far than the TDC brick, or arch keystone will come up short. Conversely, if the arch is moved in too far then there won’t be enough sticking out to make the heat break junction for the flue/outer arch assembly. Using the IT should I just set it up so I have just jusssssst enough brick on the keystone to be able to make the cuts for the taper?

Maybe I’m overthinking it, but it seems pretty important to nail that first brick.

Thanks, Mikie V.

[JRPizza]

Check out this post on my build. You can move the arch bricks in and out a few inches depending on how much you ultimately want to have exposed. I went for more of a maximum arch exposure so I would have plenty of arch to build my vent over and maximize my oven inside space. Best bet is to make a form for you arch, then use your IT to place the TDC brick forward (out of the oven) leaving enough to cut the curve for the ID. Move your form forward to the front of the brick you just located, then you can see how much brick you will have sticking out at the base using the IT to place a bottom brick. You can then do any fine adjustment you want.
https://community.fornobravo.com/for...319#post380319