Dome wall thickness question

[fxpose]

Hello,

I need to completely confine my oven, including vent and entry, within the 48" diameter corner hearth slab pictured below and would like to squeeze in as much floor space as I can.

So this is what I'm thinking:

I can build a 3" larger oven (35" vs 32") by using bricks cut down to 3" instead of the usual 4.5". I don't plan on using a soldier course.
I understand I will end up with less thermal mass but is this acceptable?

If this is all right should I keep the entire dome wall thickness uniform at 3" or can I use 4.5" bricks for the upper courses?

Or is this a bad idea and I should just stick to the 4.5" wall thickness and build a 32" oven?

Thanks!

EDIT: On second thought, using thicker courses on top of 3" lower courses may be a bad idea, structurally. I remember reading somewhere about the line of thrust.

[olddude]

Re: Dome wall thickness question

like this

also if you stand first corse on end you will get more usable area for bread and wood

just my thought's

[Les]

Re: Dome wall thickness question

I understand I will end up with less thermal mass but is this acceptable?

I see no reason why it won't work. The cast ovens are thinner than that and I believe David built his 2.5 inches thick. I personally would sacrifice the mass for the larger space.

Les...

[olddude]

Re: Dome wall thickness question

that pic sucked try this never mind lol

[Neil2]

Re: Dome wall thickness question

32 inch is a very usable oven size. If it was me, I would opt for the thicker 4 1/2 inch mass. This will make the oven a bit more versatile - like slow roasts 24 hours later with only the initial firing.

[RTflorida]

Re: Dome wall thickness question

I'm with Les on this one, go with the added space. My oven is 36" and is perfect for my family, but I really would not want anything smaller - just makes the cooking harder if you are trying 2+ pizzas or multiple pans when roasting.
Good insulation all around should allow roasting the next day without issue. Be sure to build an insulated door if you want that capability.

RT

[nissanneill]

Re: Dome wall thickness question

fxpose
I would be tempted to go 3" bricks for the first few courses and then increase this to the thicker to increase the thermal mas and 'usability' of the oven. Just make sure that the strength and integrity of the oven is not compromised in needing to apply buttressing to the thinner walls. I have a 40" Pompeii and would not go smaller. This is a little too small for the odd occassion.

Neill

[fxpose]

Re: Dome wall thickness question

Thank you all, for your replies! They all make good sense but I'm still torn which way to go.

I figured 3" was fine because most cast ovens I've seen all seemed to have thinner walls as Les mentioned.
I also decided I will use a soldier course, after all, to maximize floor space.

As far as the shallow entry goes, it will be rectangular with a flared side wall opening.

George

[dmun]

Re: Dome wall thickness question

I figured 3" was fine because most cast ovens I've seen all seemed to have thinner walls

They also have far fewer pieces to expand, contract, and crack. That said, I have a thin wall oven and I don't see any real advantage to it. If it's just the size of the dome, you can thin the dome walls where they intersect with the enclosure.

[fxpose]

Re: Dome wall thickness question

How about 3" thick walls, bottom to ceiling, and adding some layers of home brew mortar on the upper half of the dome to increase mass?

[olddude]

Re: Dome wall thickness question

your going thur the same thing i was only a few weeks back

what i found was this the larger the oven the less often they seem to use it

ie firing for just 2 pizza's

i was going to build a 48 oven but ended up with a 36

so as for therm mas depends on what your cooking seems that for pizza and
1 or 2 bread rotation 3" to 4.5" all good more insulation will be the most important thing. the thermal mas greater then 3" only comes into play once you remove the fire and slow cook bread and so forth at 3" that seems fine just how you hold that heat is very important.

another point made was if it takes 90 sec for a pizza how many can you cook at once with out burning them if your watching moving as they did at expo more room means nothing

and if you can bake 30 loafs of bread in one firing wouldn't they start to get old before you could eat them ?

so i tough wouldn't i like to use it more often
have it fire faster use less wood and just enjoy the cooking
i got a posting from a guy who has a 21 in oven and uses it all the time
so you will be fine just insulate the hell out of it

[fxpose]

Re: Dome wall thickness question

With 3" walls and enough room for 3" of blanket insulation and stucco I can lay out 35" of floor space. With stucco on the outside perimeter of the 48" circle I can do 36" of floor space.
Inner oven opening will be 18" wide.

[olddude]

Re: Dome wall thickness question

from what i've seen on this site and others make the oven smaller stay with the 3" of mas but you need more insulation

thermal mas is where the heat is stored for none fire cooking

so if your insulation is small you will lose heat fast
so even if you had 5" of mass wouldn't mean anything

question how will you be cooking for

[olddude]

Re: Dome wall thickness question

i keep trying to send you a readable cad drawing showing 2'8" in side
4 /2" wall 3" of insulation then you could stucco the out side


here is a pick of my first row on end get more room

[olddude]

Re: Dome wall thickness question

yes 3" is good my bad thought i saw 1"