Oven Exterior hot to the touch

[gsmith7712]

I just finished assembly of my Casa2g90 today and I'm curing it now. The heat has not been above 210 degrees F and the top of the stucco feels hot to the touch. I used all if the insulation an the stucco is at least 2 inches thick. Does anyone have any suggestions?

Thanks in advance - Gary

[Neil2]

Re: Oven Exterior hot to the touch

Give it a few firings. You need to work the moisture out before the insulation reaches maximum effectiveness.

[gsmith7712]

Re: Oven Exterior hot to the touch

Thanks Neil I will give this a try.

[james]

Re: Oven Exterior hot to the touch

That right. You are "baking" the moisture out of the oven and it is has to go somewhere -- which explains why the outside of your enclosure is getting hot. You still need 5+ low fires to fully cure your you.

Here are a couple of interesting things to note on oven curing:

1. Your oven home has roughly 50lbs of water in it (almost 6 gallons) that needs to bake out.

2. Water converts to steam (boils) at 212F. That is why you need to maintain a constant oven curing temperature inside the oven of roughly 300F during the first curing day. If you go over 300F, the water inside the oven will reach 212F and convert to steam -- which can cause cracking and seriously compromise the integrity of the dome.

Think long and slow.

Once the water from the manufacturing process is gone, the outside of your oven will stay cool to the touch.

James

[scotland]

Re: Oven Exterior hot to the touch

you should listen to james as he knows what he is talking about, as when i built my oven of the top of my head i made the mistake of not curing my oven properly and put an horendous crack in it which took a lot of work to repair, take your time it is worth the wait.

[david s]

Re: Oven Exterior hot to the touch

By volume, one part of water makes 1000 parts of steam.

[tmarsala]

Re: Oven Exterior hot to the touch

James-

Thanks for the curing advice, although I seem to have read many different ways to cure on the pdf instructions and this forum and your site.

May I ask you if I have done it "properly?

1) My dome was built over 3-4 weeks' time.
2) I waited one week before the first curing fire.
3) I built seven fires at 200-300 degrees each (using your newspaper advice), for seven days ( I got it up to temp and let it cool).
4) The following week I ramped it up to 300-400 for the whole week.
5) This week I have been letting it get very hot, and yesterday I partially cleared the dome.
6) The outside stucco got up to 130.
7) The only crack (so far) I have noticed appeared in the mortar during curing on the front vent arch.

So did I rush it? To be honest, I am afraid to push it to the "mother" fire.

Do you think it's ready? I feel like I went low and slow, but how slow??

Thanks.

Tom
Menifee, CA

[tmarsala]

Re: Oven Exterior hot to the touch

As a follow up to my last post for James:

I have three layers of the FB blanket ond four on top for insulation.

Tom
Menifee, CA

[SCChris]

Re: Oven Exterior hot to the touch

Tom, once the water is cooked out you're golden. When you say that you "ramped the oven up for a whole week". Were these quick burns to temp and then you stopped the burn or extended very long burns at temp? If these were short burns to temp then you may still be pushing water out, although at those temps there isn't likley to be much left. We're suppose to get some hot weather for the next few days and this is ideal for continued drying of your oven.

I think you're ready to go hot. If I were in your shoes, I'd build the next cooking fires slowly over 3 or 4 hours and then go big. The crack that you see in the arch is pretty common unless something moves you should be golden.

Best to you and your cooking!

Chris

PS The insulation over and around the oven sounds just right.

[tmarsala]

Re: Oven Exterior hot to the touch

Chris-

Thank you!

The fires the first and second week were about 45 minutes each-relatively short. The successive ones lasted about an hour an the last one (which partially cleared the dome) was about an hour and a half.

It seems to "want" to be ready-48 hours after that last one it is still reading 200+ degrees inside (with the door closed) so I know it is retaining heat well.

The cracks in the mortar on the outer arch are very minor and I expected them. After the last fire none others have developed (yet).

There is always that initial "Am I ready for this firing?" feeling - maybe I'm too cautious but I certainly don't want to hammer the thing if it's not ready!

Thanks for your input!

Tom
Menifee, CA

[SCChris]

Re: Oven Exterior hot to the touch

Tom,
If your oven was at 200+ after 48 hours you're ready and it's ready. I'm sorry that I have to ask, but is this a modular or brick oven? I couldn't find any photos.

Chris

[tmarsala]

Re: Oven Exterior hot to the touch

Hey Chris-

It is brick.

Tom

[SCChris]

Re: Oven Exterior hot to the touch

Tom,
You're going to find that your oven will heat faster and hold heat better over the next 10 or so burns. I also have a brick oven and I think it took about 10 good burns to really settle down to business. The sub-oven structure, the concrete, will continue to dry out for some time.

Chris

[tmarsala]

Re: Oven Exterior hot to the touch

Chris-

That is what I figured. Thanks.

So, when you fire and the dome goes clear, at what point do you stop and let the temp settle down? I have noticed that when the dome is reaching, say, 1000 deg. and the fire dies down, the oven may only be at about 700 deg or so.

Do you just let it go for a good hour and a half or so to saturate it?

What size is your oven?

Tom

[SCChris]

Re: Oven Exterior hot to the touch

I typically run a fire for about 1.5 to 2.5 hours. The longer burns of course saturate the oven better and so the temps stay higher for longer. These longer burns will give you more days of cookable oven temps. Early on I ran a long burn and had pizza the first night, leg of lamb the second night, hash with the leftover lamb on the third night and heated up the leftover hash on the forth night.

For pizza the ideal temp really depends on the flour you're using in the dough. If you use Cupito, you need to get the deck at 750+ to brown the crust. If you're using some other flour you'll find that that 750, on the deck, is about your top temp before the crust burns.

We're going into great farm produce season so rememeber that the low oven temps are great for drying things like over abundant tomatoes.

Please post pictures when you can.

Chris