Curing finished 42" WFO

[hodgey1]

Can people weigh in and let me know their thoughts on where to monitor temperatures during curing? I'm on day three and have been winging it. Is it the floor if so where? Is it the dome? Or is it the walls?

[irelande5]

Re: Curing finished 42" WFO

Congrats on curing hope ur cooking soon. Not sure how other folks did it but u measured half way down walls during my curing take your time most folks here have stated problems started during fast rising temp. I always keep an eye on dome too since highest temp is typically realized there good luck

[hodgey1]

Re: Curing finished 42" WFO

What I'm seeing is high temps at the top of dome and lower temps on the floor, which I expected. I've been using the sides as my gauge point but i'm not positive thats correct. The dome is running about 50 degrees hotter that every where else.

[boerwarrior]

Re: Curing finished 42" WFO

I used an InfraRed thermometer and checked both the walls and the top. Like you said there will be quite a difference in temperature. I made smallish fires but I used the walls as the gauge and for curing days 3-7 (if I remember correctly) I didn't let the wall temperature get above 300 degrees F. The center of the roof will get much hotter but I think this is OK.

You will almost certainly get a few (hopefully small) cracks. This is OK.

[SCChris]

Re: Curing finished 42" WFO

Congrats on finishing the dome and getting into the curing.

Regarding the where to take the temp, my opinion is that the dome is where the water is and where the joints are so this is where you need to be aware of the even or uneven temperatures. The floor is most often dry set and not mortared so most floors have almost nonexistent just incidental water. The dome is where the water is, and as the dome dries, and it doesn't easily dry as a single unit, there is a very real opportunity for dry hot spots and cold wet spots that create stresses lead to cracks.

It's my opinion that, by starting very slow and holding the temperatures steady for long periods the structure's moisture and therefore temperature differences can be minimized throughout the dome. The temperature difference on the inside surface of the dome bricks through to the outside and bottom of the dome to the top, is kept as constant and even "as possible" and so this minimizes the stress and the potential for cracking.

Please take note of the "as possible" because this relates directly to what you can reasonably do given what real life allows us to do. Understand that 99% of all dome owners admit to some dome cracking the other 1% are likely liars, but the bigger point is that what you do not want is a structural crack and by building correctly and curing slowly, the oven will outlast you.

Chris

PS, regarding where to take the temperature during curing... I'd take the temps all over the interior of the dome, look for hot and cold spots..

[hodgey1]

Re: Curing finished 42" WFO

As a follow up to all, I am using the prescribed method contained in the latest updated addition of "Pompeii Oven Plans Version 2.0 dated 2007-2009". My oven dome is over two weeks old since the last brick was set, using the medium duty fire bricks and refractory mortar. Is this curing method the recommended method ??? I've already completed the first three days and here shortly will be starting the forth day at 450?F today. Should I be doing somthing different?


Day 1. Maintain a fire temperature of 300?F throughout the
day and as long as possible into the evening. If you cannot
continually run a 300?F for at least six hours, repeat step 1
for a second day before moving on to Day 2.

Day 2. Repeat at 350?F.
Important Note. While it is difficult to maintain consistent,
low temperature fires, it is critical for proper curing that you
do not go above these temperatures during the first two
days, or a total of 16 hours.

Day 3. Repeat at 400?F.

Day 4. Repeat at 450?F.

Day 5. Repeat at 500?F.

Close the oven door every evening to preserve dryness and
heat.

[boerwarrior]

Re: Curing finished 42" WFO

My challenge with those instructions is what exactly is meant by "a fire temperature of 300 degrees"? I aimed for most of the interior air to be at that temperature which is why I measured the wall temperature.

I think the INTENT is more important than the actual numbers. And the intent is clear - start with small fires and gradually increase the temperature every day as the oven cures

[deejayoh]

Re: Curing finished 42" WFO

Understand that 99% of all dome owners admit to some dome cracking the other 1% are likely liars

LOL. This one goes with "how long my dome stays hot" and "how little wood it takes to get up to temperature"

[boerwarrior]

Re: Curing finished 42" WFO

DJO, that's too funny - you are so right!

You forgot to add:
- "I built my oven from start to finish in 10 days"
- "the spaces between my interior-facing bricks were so small that I didn't need any mortar"
- "my oven only cost $50- to build"
- "I cut my bricks with a hammer and chisel and the breaks were perfectly clean"
- "my oven doesn't emit any smoke"
- "we had an earthquake and my house fell down but my WFO doesn't even have a crack in it!"