81 Inch First Build (and first post)

[windage]

Re: 81 Inch First Build (and first post)

Yep, 6 feet 9 inches. I going for a low oven and fast bake times for pizza by combining the best of the pompei with the barrel, I just hope my dome support is stong enough to hold the low roof....lower being harder to hold up. I will rely on the "belt" around the oven to help, ala the Peter Moore Campanola oven build.

I appreciate the observations and feedbacks, I really do. I am not experienced at this, but have a butt-load of confidence...which makes me forge ahead into unknown areas with a 80% success rate, but the 20% failures are real "crash and burn" ugly! haha

[kebwi]

Re: 81 Inch First Build (and first post)

By diameter 6-9" do you mean 6'-9", as in six feet nine inches?

Okay, so 14" is reasonably close to 63% of 24" (a shave on the low side although I have no idea how sensitive these figures are). I guess you're just building a very low, flat oven relative to its diameter, good for pizza I suppose. I just would have expected such an enormous oven to have a fairly large entry way, but if it has a low dome, it should have a correspondingly low entry arch.

No, I'm not suggesting you did anything wrong. I am steadfast in my insistence that I have no authority on FB. I'm way too much of a novice to be telling other people what to do. I just thought it looked kinda low. Maybe it's fine for your design.

Thanks on the congrats. I'm so glad I got this far. It ain't done yet, but it was a huge milestone.

[windage]

Re: 81 Inch First Build (and first post)

The arch is 14" and the dome is 24" the dia 6-9", congrats on your first pizzas, btw. I was originally in the dark about the proper ratio of 63%, until one of my MIT friends, Thomas Massie, stopped by as I had the frames mocked up at 36". After a quick review of his Scott and Winger book, I lowered it to 24" dome height. Do you think this too low? Now is the time to change anything if I need to...going out tonight to start cutting the soldier course which will have the skew cut on the upper end.
Roger

[kebwi]

Re: 81 Inch First Build (and first post)

If I may ask, how tall is your entry arch going to be relative to your dome. It's looks kinda low considering the size of your oven.

[eprante]

Re: 81 Inch First Build (and first post)

That is a lot of thermal mass to heat up you have there. Once you get it up to temp, it is likely to stay there for a while. Very interesting build, massive scale compared to anything most of us are doing. I am glad you have a plentiful cheap source of firewood( you may have to resort to coal).
Eric

[windage]

Re: 81 Inch First Build (and first post)

installed all 11 pcs of soapstone tonight with a helper, (they are 130 lbs each !) I know I am going to catch all kinds of flack for my ash door, ...thermal loss, lack of incoming air control...etc, etc... but there it is, anyway. I will fill in the spaces with FB.

The soapstone cut easily and you can work it with hand tools, I used a block plane, chisel and knife !

Roger

[ThisOldGarageNJ]

Re: 81 Inch First Build (and first post)

Hey Roger,,
Great oven, very Impressive... Good Luck to you when you open


Cheers
Mark

[windage]

Re: 81 Inch First Build (and first post)

Soapstone has great properties as the hearth covering floor for a pizza oven, also seen in these videos; the first is Campanola in ILL by Peter Moore,

YouTube - Building of a wood-burning pizza oven.

This one is Keste Pizza, NYC;

YouTube - Keste Pizza, NYC; Burrata, Cherry Tomatoes, and basil in the woodfired oven

From the website of the place I got my Brazilian Soapstone;

Soapstone Firebrick Fireplace Firebox :: M Teixeira Soapstone

"A Soapstone firebrick's special mineral properties make it ideal for lining fireplaces. Soapstone can withstand great changes in temperature without cracking. A Soapstone firebrick is so dense that it absorbs heat and then radiates slowly for hours, improving your fireplace's efficiency."

I haven't used my oven's floor yet, but it feels smooth and should be easy to work on.

Roger

[trockyh]

Re: 81 Inch First Build (and first post)

Hey Roger, very interesting build, looking forward to your progress. I was thinking of using soap stone for my counters, love the stuff. Didn't know it could be used inside the oven.

Cheers,
Tom

[windage]

Re: 81 Inch First Build (and first post)

Got alittle more done last night, brick on hearth and a few pcs of the soapstone...60mm x 300mm x 1000mm from;
M. Teixeira Soapstone
85 Myer Street
Hackensack, NJ 07601
Ph: 201-525-0024 x 102

[windage]

Re: 81 Inch First Build (and first post)

Yeah, I was wondering which way the heat would go, from dome to flue or the other way around....
The swirling concept might be accomplished by angling the incoming air slightly so that is favors the right side wall, the fire side. The roof bricks just above the arch would have a path formed from the top of the arch towards the left and the flue would lean upward, towards the right...so...the air would form a slow rotation counter clockwise inside the oven. Works on engine intake manifolds...after all, every bit of hot air expelled from the chimney top is sucked into the front of the oven, right? Might as well get every bit of efficiency out of it.

I have thought about wrapping a few turns of 3/4 inch copper tubing around the outside of the dome, under the perlite and hooking it up to my hydronic floor heat system...pump, valves, resevoir, load....sounds simple. One could also use it to take down the oven temp if needed too.

Great discussions.
Roger

[shuboyje]

Re: 81 Inch First Build (and first post)

Roger,

I've thought about similar vent designs, almost creating a secondary heat exchanger like a 90+% furnace. I do have some feedback on it though. In naples they built the ovens with a vent going back over the oven to the middle then up. On another forum a member with insight and knowledge of these ovens claims it does little if anything to heat the dome, and that in fact the goal is to transfer heat the other way, from the dome into the flue to improve draw. The next concern is if it does work. The heat exchange would have to be balanced so you are not cooling the flue gases to a point that they are cooler then the dome and start stealing heat on the way up the stack. Finally when cooling gases you have to think about condensate. It shouldn't be an issue due to the temperatures involved but as you cool air you lessen it's ability to hold water.

Now what would be cool is to use the heat in the flue gases for heat or to assist a hot water heater. A section of single wall metal stack with fins on it and a fan blowing over it could produce a nice amount of heat IMHO...I've thought about trying that on my oven.

[windage]

Re: 81 Inch First Build (and first post)

Wiley,

I agree with the insulate theme, and plans include many bags of perlite...(there are already 15-4cufts on site)...there are 4 bags alone in the hearth floor. Not only to save on fuel, but to retain heat and allow the masonry to do it's thing properly.

As far as wood is concerned, we can buy "seasoned" hardwoods; white and red oaks, hickory, beech and hard maple for $30 to $50 a pickup truck load. We are in the middle of the Appalachian hardwoods and very rural, so there are always felled tree tops to get and thirsty guys with chainsaws to get it.

I am playing with the idea of creating a "swirl" trench in the roof of the dome as it joins the arch, coupled with a directional opening in lower portion of the outer arch to direct the air in a circular motion. This will be an effort to use the combustion air to direct convection currents evenly around the dome. Haven't read or seen anything about this idea, just seems right.

This oven will function 11AM to 12 midnight as a pizza oven, only baking hearth breads and cinammon rolls in the early AM as temps are lower with a door on. I know this is asking alot to "dual purpose" this oven...but what if it could be done?

I have to say that you are a great bunch on here ! After only posting yesterday, I am getting all kinds of help and welcome. I have been reading the forum for several years, planning this oven and researching, but haven't posted until I had something to show. Thanks all.
Roger

[Wiley]

Re: 81 Inch First Build (and first post)

Wow!
I'm impressed with the size of your undertaking. As long as you have vast supplies of inexpensive wood to burn, insulation is probably not necessary. I mean once upon a time stone castles were heated with open fireplaces, it rquired whole forests but it was done.

For most of us on Forno Bravo "insulate insulate insulate" is sort of our mantra. We try to capture and retain as many BTUs as practical from the wood we burn. The price of wood and the quanity you burn will (I expect) be reflected in the bottom line. But if you have the wood and if it "pencils out" to be more economical in the long haul to burn more wood rather than insulate, then go for it!

I'm guessing you are going to have a poured support structure outside of the lower vertical section of the wall to contain the fairly sizeable outward thrust of such a wide low dome. Something like the guy in the video did, or do you have another plan?

Please keep us posted as you progress.
Bests,
Wiley

[windage]

Re: 81 Inch First Build (and first post)

Roger,

I had noticed your oven was gonna be similar to that one...guess that was because it was on purpose, lol. Are you gonna pour a reinforced abutment like he did? Are you gonna do the "squirrel tail" vent? I've noticed the squirrel tail vents and soap stone hearth in most of Peter Moore's ovens pictured online, curious to hear how it all turns out.

I'm in the northeast suburbs, up by New Baltimore...but I work in the union building trades so know the whole area well as I see all corners often. I spent the last month working on a school in Roseville...

Yes, I will "pour" the surround using rebar and perlcrete...it works kinda wierd, more like pushing it in..
The vent?...I may build it from bricks, but dont like the cast "lids" Peter uses...thinking of going with flu liners laying on their side and mortared in place. I am also thinking I will build the covering from steel frame and dur-rock and fill with loose perlite.
I really need to source the best price on some K thermocouples to bury in the dome and hearth so I can get temps...any sources (aside from OvenCrafters?)
Roger