Oven Curing

[SCChris]

Re: Oven Curing

On further inspection, no heat related cracking has been found. On Sunday I ran to Lowes and gathered steel studs and channel for the surround and I now have a steel box frame built 38? high around the dome. The next task is to apply ? inch thick Hardie Backer to the sides and back of the steel and block structure. This weekend, I'll line the interior of this outside wall with unfaced fiberglass insulation; this insulation will support the rockwool, RW, bats. I?ll use these RW bats directly against the dome. I have 3, 4 cuft, bags of vermiculite to fill in what holes I can't easily get RW or FG insulation into. I?ll be using all these materials to level out the insulation within the box. I'll be leaving some space around the insulation, next to the studs, to provide air movement and hopefully minimize humidity that would chew up the steel framing. Before I do a final pack on the insulation and dump the vermiculite I want to get the curing fires done and get the OMG fire behind me. This weekend I push forward with 500 and 600 degree burns and begin using wood rather than LP.

Sorry I don?t have any pictures, I?ll add some soon.

Chris

[jmhepworth]

Re: Oven Curing

Everything sounds good.

Joe

[SCChris]

Re: Oven Curing

Last night I started the burn at 5:30PM and just finished at 2:00PM 20.5 hours and a max temp of 540 degrees. I now have cement board surounding the oven and this is gong to help to get the maximum amount of insulation within this structure.

Tonight I'll run another long burn and figure that I'm 95% there as far as curing. I know the cure instruction indicate run a sieries of long burns ending at about where I now am at, but I want one more long high temp burn and a 2 or 3 carefull, non temp shocking, wood burns ending in the OMG 800 to 900 degree burn. So I guess I have 3 or so more burns to the oven being ready for anything.

Chris

[SCChris]

Re: Oven Curing

No more fires since Oct. 31st, :-( but I have the structure insulated top to bottom, front to back and left to right. The roof structure is coming along and I hope to get the box water tight this weekend.

Chris

[SCChris]

Re: Oven Curing

Status - November 23.

I have been running up the temp by use of the propane torch and the last burn, several weeks ago, I held a maximum of 540f, for several hours, at the end of 20+ hours of gradual heat increase. Yesterday, Sunday, I started the torch at 9am and built the temp with the door mostly closed, for about 1.5 hours and then started adding almond wood. Once I had a good fire I removed the torch and built the temp to 350 at the top of the soldiers somthing about 500 at the top of the dome. With the door open and keeping the fire low, I added a package of beets to roast and 45 minutes later added a rib roast with foil covering the top, sitting on a bed of roasting vegetables. Once the roast was out I added wood and built up to just shy of a full raging fire. After 20 minutes the dome was clear of soot and reading 850.. I sacrificed a quick margarita pizza to the oven, not quite sacrificed it looked like hell but tasted fine.


Chris

[ThisOldGarageNJ]

Re: Oven Curing

not quite sacrificed it looked like hell but tasted fine

I like to say If its pretty take a picture then eat it... If its not... Just eat it....

Congrats
Mark

[SCChris]

Re: Oven Curing

The last 2, all wood, burns have been to high temps. No smoke where it?s not supposed to be and no observed cracks, yet. I?m happy that the propane, LP Gas, method of long sustained, temperature controlled burns, cured things just fine.

Thanks for all of those who are contributing to, and those who have contributed to, the curing forum for your help! For those coming after, I?ll do my best to lend a hand where I can.

Chris

[spazio]

Re: Oven Curing

I just lit my first fire today. It's been pretty cold (around freezing for the better part of several weeks). The dome has been curing for almost a month while I built and insulated the enclosure. I've been running a fan/heater inside the dome for most of that time, so it's probably well pre-cured and dried out. The ambient humidity has been fairly high, plus I've had a tarp over it for the first few weeks while the heater was on, so much of the moisture likely got trapped and helped keep the mortar damp. Temp inside was probably up to about 100 f or so much or that time. It also sat for a while recently at ambient, about 30 deg. Today's fire was about high 200's for about a half hour, and now it's cooling off. I'm hoping to do two fires a day, morning and evening, as long as it drops to about 50 or so. I'm trying not to let it drop to ambient for now, that's scary cold. Any hints for cold weather curing? Where should I be measuring the temps, top of the dome?

[ThisOldGarageNJ]

Re: Oven Curing

Any hints for cold weather curing? Where should I be measuring the temps, top of the dome?

Hi Spazio,, I always measure my temp on the floor, the simple resaon being is that i will always have a constant reference number no matter what im cooking and i have learned to relate that number to my recipes..(hope that makes sense to you), I havent cured in cold weather, but my suggestion would be just ramp up to temp slowly, come down slowly this should help avoiding any massive thermal shocks.. hope this helps
cheers
mark

[SCChris]

Re: Oven Curing

When I cured I measured the temperatures all over. I cured with long running fires, starting about 5pm and running till about 9am. I did ramp up slowly and try to stay under the desired temps and then just let everything soak in the ongoing heat. I have seen several post using “heat beads”, charcoal briquettes here in North America, to run long sustained burns. If I didn’t use a burner and I lived in colder areas, I would certainly consider using charcoal briquettes, at least for a couple of the early burns. I liked the long cure method, it made sense to me to keep it hot so as to drive the water out and keep it moving out.

Chris

[spazio]

Re: Oven Curing

Measuring temps seems to be an inexact science. I'm using a remote reading infrared thermometer (a decent one, don't even bother with one that's less than $75 or so). The temps with the fire going incorporate a certain amount of reflected heat, so they often don't seem to tell what the actual dome is doing .
I saw about 400 at the peak today, with about 200 at the second row up (my second firing) and almost 500 on the floor where the fire was. A few hours after the fire's out it's down to about 200 at the top, but still pretty hot on the floor (as Mark mentioned, that seems a relevant place to measure).
Ran the fire for a few hours. Tomorrow I'll try a longer burn and look for around 500 at the top.

[spazio]

Re: Oven Curing

Yo, sorry about that hi-res photo, I'm still figuring this camera out. I'll post a bunch to the photo gallery soon.
Snowing like crazy here, I'm about 20 minutes south of Bethlehem, PA. Supposed to have maybe a foot tonite.

[spazio]

Re: Oven Curing

Saw 800+ at the dome yesterday, though that was transient. Settled in at about 650 for about a half hour during the peak of the burn. Floor similar, though that went down quickly once the coals were moved away. Fired in the morning, done about 1 pm, by late evening it was still showing about 250 through the entire oven. Probably have to add an hour or so to the peak of the 3 hour burn I've been running to heat it enough to be really useful. NO cracks anywhere that I can see; I attribute this to the long, slow cure with a heater/fan for several weeks before first firing. My wife is firing it today; she wants to do a roast. Still got cosmetics to do, but I think this thing is up and running.
Getting mixed messages on softwood vs hardwood. I've been running about 1/3 soft, rest hardwood. Any ideas?

[ThisOldGarageNJ]

Re: Oven Curing

Hey Spazio...
Congrats... I try to burn softwoods and cutoffs, scraps etc for my warmup.. I do some building and we throw the scraps in the back of my truck,, easy to light,, but they burn quick,, When I am getting serious with the fire I switch to my well dried hardwood pile,, I save my fruitwoods for cooking dirty steak on the coals,,
Cheers
Mark

[Wheels1974]

Re: Oven Curing

The last 2, all wood, burns have been to high temps. No smoke where it?s not supposed to be and no observed cracks, yet. I?m happy that the propane, LP Gas, method of long sustained, temperature controlled burns, cured things just fine.

Thanks for all of those who are contributing to, and those who have contributed to, the curing forum for your help! For those coming after, I?ll do my best to lend a hand where I can.

Chris

Chris,
Well done mate everything sounds perfect. I'm soon going to start the curing process. I'd like to know how big is the void opening on your chimney?

Cheers
Dean