39 inch Corner Build

[danhem]

My rope was fairly flexible/compressible as I stuffed it in conformed to the gap. So my round rope became elliptical to fill the gap. I would think 3/8" or maybe 1/2" would be fine. I think my gap was about 1/2" and I used 3/4" or 1" braided rope. 61A Ceramic Rope 8.25.12.JPG

Reading here that quite a lot of the better builds have used a heat break of some kind. It hadn’t crossed my mind to use one but the more reading I do on the vent and outer arch I do the more I see the heat break as being a best practice.

knowing that supplies of such material is limited here in Thailand, I wonder what kind of material can be used for the heat break. Could I use some of the left over ceramic fiber board for this? And I’m guessing that the heat break is positioned in between the inner dome and vent tunnel as displayed in your picture?

[JRPizza]

Yes the heat break is between the dome structure (arch part) and the rear vent arch. I went with L shaped bricks for the rear vent arch so that they had a gap between the vertical face of the dome arch and the top surfaces of those same bricks. If you go to post #143 you can see a picture someone posted and I copied the design. With my heat break I was just trying to decouple my vent from the dome in terms of thermal conductivity. I was not trying to use the gasket to insulate the dome from the vent, only to prevent hot gasses from trying to exit via the gap instead of going up the chimney. Putting the gasket on top of the inner arch (along the horizontal surface) seemed like it would prevent the gasket or pieces of it from falling down onto my landing and getting in my food. I added the high temperature caulk just to make a final seal along the joint. I believe I have read suggestions that with a similar design you could apply some insulating concrete along where I put my caulk and achieve at least as good of isolation that I did, and even if it cracks it won't be falling into your food.

[mdbronco]

Old thread JR but if you get this, any chance on sharing some of your CAD files for the 39" corner? This looks bang-on what I'm trying to do...

[JRPizza]

Sure thing mdbronco , file attached below. Had to zip it as the forum software does not recognize the cad files. Have you used Freecad before? It is what I use and what the format the files are saved in. Let me know and I might be able to export in another format (maybe). Also let me know if you have any questions after you open and check it out.

[mdbronco]

Thanks so much JR!!

[Shaners15]

I've been working on my oven for a little while and have been debating starting a build thread, as I probably won't have much to add in terms of artistry or inventiveness over the excellent work already posted on this forum. That said, I thought I would share what I have done and hopefully continue to get support from the great folks that have been helping me so far and others that might chime in. I have used CAD for my initial layouts that some may find interesting.
I'll start with some pictures to show progress to date. First picture is the patio where the oven will be located. My Wife and I stained it ourselves and were pretty happy with the way it came out. Note we had supports sunk in the concrete for the uprights needed for the shelter we wanted to build. We weren't totally sure how big a structure we wanted or how the oven might look so I made a layout using Freecad.

Hey JR! Its me again, do you have any plans in a concise manner? Like Simple to understand the dimensions? I am not too good with this CAD stuff, I tried, but out of my reach Sorry to keep bothering you friend

[JRPizza]

Not per se. If you decide to build a 39" you should be able to mine most dimensions from this thread or the one linked below. Anything else you need let me know and I can probably pull them from my models

https://community.fornobravo.com/forum/pizza-oven-design-and-installation/getting-started/355718-hearth-size

[Shaners15]

Not per se. If you decide to build a 39" you should be able to mine most dimensions from this thread or the one linked below. Anything else you need let me know and I can probably pull them from my models


https://community.fornobravo.com/for...18-hearth-size

Jr, I want to build the 39" as we spoke about. You have convinced me its the perfect size. I have spent time on this thread and tried to draw it out, but it doesnt seem to add up. If you have some time to spare, can you put a concise dimensions of hearth, oven? I know I am asking for a lot but a concise picture plan will really help me visualize and replicate. If its too much work, please dont worry!

[gvegasg]

Great build JR. I have couple of questions when you have an opportunity.

1. What were the final dimensions of your hearth slab? Were they ~72 for outer and ~48 on inner parts?
2. How thick is the hearth slab, 5 inch?
3. Can you please confirm that there are no other support below the hearth slab except outer cinder blocks? If yes, have you seen any issues?. I would like to have to have access to the whole section at the bottom but seen number of corner builds having additional blocks under the slab.

[JRPizza]

In answer to your questions,
1. Yes, pretty much. Dimensions can be read from my post #3 of this thread in the first thumbnail pic. My back walls of my stand used 4 full length CMU's (cinder blocks) @~15 5/8 plus a half block @~7 5/8, where the short sides were 3 full CMU's long. See pic below
2. I was shooting for a 4" slab but just measured and I guess I hit about 3 7/8 of concrete sitting on 1/2" hardibacker.
3. No other support but the CMU's. I put a liberal grid of rebar tied into the rebar in the stand and made sure it was located in the center of the slab. It sure seems to support the weight of the oven (no cracking or sagging) and I am very glad I left the underside open as much as possible. Didn't really use the space much the first year or so as it gets wet there in the winter, but I made a raised platform using pallets and am surprised at how much wood I can pack under there. I hear folks say they wouldn't want to crawl under the hearth to fetch wood but other than bumping my head a few times and maybe fighting a few spiders I don't have a problem accessing the furthest reaches.

[david s]

You need some of these

https://www.westernlandscape.com.au/shop/grey-block-15739-45-degree-squint

[gvegasg]

JR, do you think 6” slab with 2-3” gravel would be good enough for the ground foundation?

[JRPizza]

That is out of my area of expertise, so I'm probably not the best one to answer. That said if your sub-soil is compacted and you use plenty of rebar in the slab you are probably good, at least until the big one hits.
Maybe one of the concrete guys on the forum will weigh in.

[NathanR]

JR, do you think 6” slab with 2-3” gravel would be good enough for the ground foundation?

Yes. Assuming you’re in LA, I would include rebar that will stick up into your base blocks.

[Buzzard Bluff]

Hi JR
Thanks for documenting your build so well. I will be borrowing heavily from your experience as I'm planning a 42" corner build. I plan on having a roof built over the oven that will be an uninsulated sort of portico with a low sloping metal roof. I'm curious how you flashed the chimney without creating a dam on the roof when it rains. Did I read correctly that you bought your chimney pipe and fittings from Menards?
Thanks again
Steve