80cm dome, air chamber space

[Lucag]

Hello everyone, is there enough space at the entrance for this 80cm dome ? It’s the yellow area. If not, I will have to make the dome smaller I am afraid.

[Lucag]

This is the link to the plans:
https://www.dropbox.com/s/dk4ss21f89..._7632.PNG?dl=0

[SableSprings]

Lucag, 40 cm is plenty wide for your oven entry (IMHO). You can easily work into the oven with a peel and can fit a sheet or roasting pan through the opening width (meat, chicken, Focaccia, etc...) The ideal inside dome height for your 24.6 cm entry height is 39 cm (giving you the gold standard ratio of 63%). You should have no problem creating a nice smoke chamber above your landing that feeds into a 15 cm (ID) chimney pipe. (It would be good to create a split oven side view as well through the CAD program...just to make sure everyone is able to get everything correctly "assumed" in the intended layout ). Looks really good at this point!

p.s. If you can create a 800x600 pixel/resolution size on your photos before uploading, they will be fairly small in file size (max upload size here is about 1.2 MB/picture) but plenty big for viewing full screen.

[Lucag]

Hello! Thank you for your reply.
i am not sure I understood you correctly.

24.6cm is not the height but the length of the yellow area.
the yellow area is width 40cm x lenght 24.6cm

The dome height is 40cm in the center so the door height will probably be 25cm (63% of 40)

Not sure about the yellow area height.

I suppose the yellow area height will be higher then the door but not sure how high I should attach a chimney pipe.

Another doubt is how to make the fue width larger than the entrance width like many suggest.

The dimension from this website are:
http://pinkbird.org/w/How_to_build_a_pizza_oven_flue

41cm vault height
46cm Flue width

But I don't know how to reflect these in my design.

The Flue width is my yellow area?
what is the vault height my entry door height?

Thanks for your help

[JRPizza]

Lucag, in your drawing, the bricks labeled as "A" would typically be the inner arch. They would be a little shorter at the bottom of the arch and get longer as the dome "pulls" back as it goes up due to curvature. See the first picture. The vent area, typically a forward and aft arch, sit in front of the inner arch on my oven. The aft arch actually sits partially over the inner arch as a way to get more room. You can even incorporate the inner arch into the vent eliminating the aft vent arch, but even that is going to take more room than what you are showing. You would still need room for an opening and the forward arch. Does this make sense?

[Lucag]

Thank you very much for this reply.
I now see why I will struggle with space

What do you think of this?

1) if I use only half brick at the bottom for the inner door arch (but it gets bigger when we go higher, to match the dome) , and I position in a way that it slightly come out from the main 40cm entrance (at the bottom)

2) This will give me space for one full brick in the fue (23cm), Do you think I can work with that or I need 1 brick and a half for sure?
My bricks are 23cm

Another compromise I could make:

- 7.5cm ceramic blanket instead of 10cm
- move the oven back and use a smaller internal diameter:
75cm instead of 80cm.... sigh

[SableSprings]

Sorry Lucag, I was thinking the yellow area on your drawing was the width and height of your proposed entry...instead of the width and depth that you intended. My mistake...I didn't mean to confuse you. As JRPizza noted, that 24.6 cm depth is going to be too small for a "normal" entry arch/chimney vault. David S, one of our casting experts has a very functional cast oven that is about 54-55 cm inside diameter. Going smaller is not going to stop you from being able to make great pizza. If you haven't already acquired your firebricks, with your space limitation, you might consider casting your oven. You still would use firebricks for the cooking floor, but your oven dome and smoke chamber/chimney base walls would only be 5-6 cm thick. Also consider that there are WFOs that do not use a chimney...they just have the front opening in the dome. Not ideal with a smoky fire, but it is an option and does work to cook pizzas.

I think you might want to take a look at these links. (There are many other great builds on the site, I just picked two links to threads of interest.) One has some good pictures of the traditional entry arches and chimney vault, while the other is a well documented cast oven (on its pages 5-6 are some pics of casting the front smoke chamber/chimney pipe attachment).

https://community.fornobravo.com/for...ing-refractory

https://community.fornobravo.com/for...sted-over-sand

Hope this helps a bit...

[SableSprings]

Lucag, I thought you might be interested in looking at the dimensional drawings for the Forno Bravo cast Giardino 70 oven and recommended stand. I've inserted a link to the pdf for it below. It is a smaller oven, about 70 cm diameter cooking floor, but is very capable and versatile. I also wanted to make sure you realize that a smaller, cast oven will take less wood to fire up for pizza...depending on where you live that alone can make a difference. Where are you located? It helps us to give you advice in your planning stages.

https://www.fornobravo.com/PDF/giard...ino70-dims.pdf

[JRPizza]

Lucag, you have options, and that is a good thing. In addition to a totally cast oven, you can consider just a cast vent, which several builders have done, or doing something similar to what I did where you build your rear/aft vent arch either partially (like I did) or totally over the top of your inner arch. Building it over the inner arch would result in a large reveal to place your door against, but would also let you make the smallest brick vent. They you would start your chimney at the front of the opening but build it back towards your oven to make a square opening (which is similar to what I did). An 80cm oven will not need that large of a vent - you just need to study some threads and figure out what you are going to do. I tried to take good pictures of my build so maybe looking at it will help you figure out which way you want to go. Also do a search for user "gastagg" and cast. He originally built a brick vent but it got ruined by the weather. He replaced it with a cast vent and I believe was very pleased with how it turned out.

[Lucag]

Thank you everyone for the precious comments! I will look into casting the air vent but before I would like to consider all the option I have with the bricks.

Please have a look at the attachment: I have reduced the diameter at 70cm...
Can you comment on position and size of the ARCS and the vent ?

Thank you again!

[UtahBeehiver]

If you are going to do what is called a tapered inner arch (recommended due to it is better and a smoother dome tie-in) if requires more than a 1/2 brick than you have shown. There are dozens of examples of tapered inner arches on the forum

[Lucag]

That’s unfortunate, beehiver
1.5 bricks is not enough because will it cause structural problem or because compromise the oven functionality?

What would be a good size for the opening in the fue area for a 70cm oven? Maybe if I find this out I can come up with a solution.

Do you have any suggestion to make a 70 to 80 cm brick dome work with my dimensions (137 round base). I will consider casting the smoke chamber / fue but I would like the oven to be in bricks

[Lucag]

Maybe I can plan the first external arc in a way that starts on top of the internal arc. This will give me the necessary space I suppose

[david s]

For my design I had a similar problem in requiring the flue gallery to be really shallow in order to make it as compact as possible and fit on a 910 x 910 mm footprint. I have achieved this by placing it on top of the oven mouth rather than in front of it. Also by designing a generous volume above the oven mouth so smoke is drawn more efficiently by its inverted funnel form to the flue pipe. This however requires compound curves which are easy to do with a casting, but extremely difficult with brick units. To explain what I mean, take a look at the photo of one of my ovens that I deconstructed.
https://community.fornobravo.com/for...422#post398422

[Lucag]

Thanks David, So far this seems to be my best option: I can cast the whole entrance and have the cimeney near the entrance.
i will go this way probably, BUT...

Before I completely discard the brick solution, I have one question that remains unanswered, maybe you can help. In an ideal word with infinite space available, with a 70cm internal dome, what would be the ideal dimension for the entrance width and length, and how big the hole that will connect to the chimney should be in width and length ?

I feel that if I have this dimensions I can sort out the problem. I am quite confident that I can create a solid tapered arc with 6cm x 11cm bricks, placed vertically and create a “hole” big enough to avoid the fire coming out from my entrance.