Curing strategy

[james]

We've been talking with the producer of the Modena ovens, and I want to open a discussion on modifying our recommended curing strategy. Their recommendation is to build a series of low and growing fires, and for keeping them going all day at the slower temperatures. The theory is that you are baking the moisture out slowly and consistently. The idea is to keep the low fires going all day, and close the door before you go to bed, and start again the next day.

The recommendation is this:

Day 1; 300?F
Day 2; 350?F
Day 3; 500?F
Day 4; 600?F
Day 5; 700?F

It can be tricky and laborious keeping a fire burning, not going out, and not going over the 300?F and 350?F, but it makes sense. There is a chance this might minimize cracking a little if you do it right. It is still absolutely critical to not get the oven too hot in the early days.

Before we make the standard procedure for everyone, I wanted to throw it open to conversation.

What do you think?
James
What do you

[ballard6449]

Re: Curing strategy

James,

I had my WFO built by a pro (did not have the time, no tools, and not much talent to do it myself) using the Pompeii design. He came over today and we lit the first fire. Although he did not specify the daily temperature goals, he did recommend that we start with a small fire and keep it burning all day (if possible). The next day build a little bigger fire and keep it burning all day, etc. for the next 7 days. The gist of his comments were keeping the fires buring throughout a longer period of time would give us a better cure/drying....

[james]

Re: Curing strategy

We can take that as a yes. :-)

I am guessing it was Keith. Hope your oven is working great.
James

[Acoma]

Re: Curing strategy

James, I'll give it a shot once my oven is complete. It does make sense to maintain the temp for longer periods. I would even think that those in curing stages right now can move to longer periods. What if several days go between cures, just go to next temp level once able for the day? Was that brought up?

[RCLake]

Re: Curing strategy

This will be an interesting thread to follow, I'm guessing I'm at the halfway point of the dome. I know I needed to research threads on peoples experience on curing and this approach may be fine. By the way I've got an IR gun for Christmas and was wondering is it the dome temp. or floor temp or even the air temp this is the focus? I've got a 500 degree F oven temp gauge I'll also use.
I also would like input on having insulation on or off.
I don't ask much do I?

[gjbingham]

Re: Curing strategy

I agree that the standard early fires of 100 and 200 degrees are probably not that effective at drying out the dome. The thing will barely get warm on the inside after an hour of small fires. Your suggested burn schedule makes sense for that reason.

The all day burns sound problematic to me. I don't have a job, other than normal round-the-house stuff, and I'm not sure that I could do the suggested burn schedule effectively to that degree of accuracy over the course of a whole day (or days and days).

I'm wondering if there's a common household device that got hot enough to maintain the temps over long periods of time (like a hotplate?). Something that didn't cost an arm and a leg.

George

[Acoma]

Re: Curing strategy

RC, this would likely be air temp. The goal is to have heat dry out moisture from first point of contact, which is internal face. Then the moisture is driven out with increased temps, which is deeper within the brick, and backside of it, as well as the cladding. This goal is to slowly drive out, and dry out the moisture. If you go to high at first, the brick and morter crack due to moisture present. Make sense?

[ballard6449]

Re: Curing strategy

James,

That would be "yes" and "yes". Keith and crew did a great job constructing our outdoor kitchen.

[Guerito]

Re: Curing strategy

For some of the earlier lower temperature burns here is a thought. We could get a steady flame from one of those weed burners that the "pyro" guys were using for fire starters a few months ago. A 5-gallon LPG tank and the burner from a turkey deep fryer should do it for most folks.

My $.02

Guerito

[Frances]

Re: Curing strategy

After spending so much time building the oven, I found the most difficult bit about curing was just lighting a small fire, letting it go out, and not doing anything else with the oven for the rest of the day...

So from that point of view, messing around with a small fire all day long would have been great! So I'd definitely give it try if was doing it over...

[david s]

Re: Curing strategy

I use one of those gas rings with a long braided metal hose attached to a 9Kg LPG gas bottle, set it at 1/2 throttle and let it burn all night. It doesn't go over 200 C which is safe. We use the procedure to dry out clay work in our kiln prior to biscuit firing to avoid steam explosions. Gas flame is the best for eliminating water. I then light a wood fire and keep it gentle by using heat beads. Build up slowly until all the damp patches on the outside stucco are gone then build up to 400 C. Hope this helps.

[RCLake]

Re: Curing strategy

RC, this would likely be air temp. The goal is to have heat dry out moisture from first point of contact, which is internal face. Then the moisture is driven out with increased temps, which is deeper within the brick, and backside of it, as well as the cladding. This goal is to slowly drive out, and dry out the moisture. If you go to high at first, the brick and morter crack due to moisture present. Make sense?

The concept makes sense and I understand the concept but I'm still confused about what temperature to be measuring. Day two and my floor is 250-300, dome 400+ but air at 160(could be a bad gauge, I'll put it in the oven to check later today).

So I'm shooting to have the dome 350-400 for today.

[Acoma]

Re: Curing strategy

RC, I was wondering that too. Are we to do the curing temps, gauged on air temp within the oven? I would think so based on the concept of ovens built before without the ideas of thermocouples. Hopefully James, DMUN, RT, Ken, or others with a clear answer will tell us.

[james]

Re: Curing strategy

Either air temperature inside the oven, or the average temperature of the inside of the dome. You can test it with your hand or an infrared thermometer.

It is definitely not the temperature of your thermocouples, as those are set deeper in your dome and/or floor -- and if the thermocouple hits 350?F, the inside of your oven will be a lot hotter than that; which would be bad.

It's really important to be patient and not go too hot inside the oven. Very important.

James

[james]

Re: Curing strategy

Do you remember Ghostbusters? Don't cross the beams. That would be bad. :-)
James