pompeii oven construction began today

[oasiscdm]

Hey Russell who is getting 10 days?. Best I have done was 5 days having heated it to 550c after a pizza cook. Keep it going until I get outside brick temp of 400 and inside of 480 or more, take fire out seal and it equalises at 440, from there drops about 40 - 50c deg per day. A little faster if the door is taken off to much. I tend not to use it if it drops below 100c. would love to get next one to maintain for 7 days then it would heat up quicker for pizza on Friday nights.

My next oven I am going to double the insulation I used on this one. around and under.

[UtahBeehiver]

Maybe 10 days is a stretch for "cooking" heat but here is the link of claim to fame by Randy J.

http://www.fornobravo.com/community/...?r=5539921&p=2

[RandyJ]

I would also say that it is pretty much a stick and move process. And if you have the mortar just right and the bricks properly wet you can make it a little farther up the dome. I was either lucky or dumb but I did mine like that all the way to the top. As soon as I had 3 bricks in it seamed to hold ok.

As for insulation the Moro the better. I used 4" of ceramic board from McGills warehouse under the oven. Then I did 3" of ceramic blanket over the top of the dome and filled the enclosure with 36 cf of vermiculite over the top of the insulation. I also did heat breaks at the dome to vent ant floor to vent. AlSo I put paver stones under everything that acts as drainage if it should get wet.

I am seeing temps around 700F floor and 750F dome the next day the next day will be mid 600F range somewhere. With the insulating door in place it will take up to 10 days to cool to under 100F I normally do a batch of bread on day 2 or 3 but nothing past that yet. Note this is with outdoor temps below freezing and sometimes well below 0. I am very happy with how it turned out.

Randy

[paulages]

2. What do you consider slow heat-up? 2-3 hours for a white dome is not uncommon. Insulation has changed over ten years, recent rule of thumb is that CaSi board or blanket is twice as efficient as P or Vcrete. So most recently, a min of 2" CaSi is recommended under the floor with 3-4" better. This mean 4" min P or Vcrete or 6-8" optimal under the fire brick floor. Maybe the 2.75" of Pcrete (1.375" equiv. CaSi) under the old oven was not enough floor insulation so the concrete base acted as a heat sink which I guess in a sense too much thermal mass. My oven has 3.5" of CaSi and FoamGlas under the 3" thick firebrick floor, 3" of ceramic blanket and 3" of Pcete on the dome. IMHO, insulation is a key component to a high efficient oven. The new generation ovens are getting 4-5 days of workable cooking heat. One recent oven builder is saying they are getting 10 days.

The floor insulation is something that has obviously changed. The plans when I build this oven called for a concrete hearth directly beneath the floor bricks, with pcrete under that. If you look through my thread you'll see where I suggested flipping that, with the floor bricks being the only thermal mass in the bottom. Glad to see that is the norm now.

[david s]

The floor insulation is something that has obviously changed. The plans when I build this oven called for a concrete hearth directly beneath the floor bricks, with pcrete under that. If you look through my thread you'll see where I suggested flipping that, with the floor bricks being the only thermal mass in the bottom. Glad to see that is the norm now.

It all depends on what you want your oven to do. For a bread oven a very thick dense floor is good because high temperature wicks away into the cooler part of the floor. This results in more heat storage and a reduced tendency to burn the bottoms of bread loaves. You can do multiple loads of bread without the temp dropping off so fast. The downside is that it is really difficult to keep the heat high enough in the floor for continuous pizza cooking and the oven takes longer to heat up initially.