Oven curing/insulation

[cecilB]

Wow! It's been a long time since I've communicated on here! Howdy, ya'll!

Ok, so for the entire winter the dome has been covered with plastic - everything was done except the final brick in the very top of the dome, and the outer arch with the vent. A few days ago that was all completed.
Now, could I cover the dome with the blanket insulation now- I have three layers worth - today or tomorrow? Or should we let it sit for another week? The only mortaring done was with the very top brick in the dome and the outer arch...the rest of the dome has been curing all winter!

And then we should fire cure it AFTER the insulation is in place - slowly starting with tiny fire or heat gradually increasing the heat?

I REALLY want to get this going and practice the pizza making with it in time for a big graduation party here at the end of May! Think it can be done?
I hope so.

[Neil2]

Re: Oven curing/insulation

"And then we should fire cure it AFTER the insulation is in place "

Two schools of thought on this. My advice is to put the insulation on then fire it. I think that this will contribute to a more even curing. Other have fired it before putting the insulation on - with no ill effects it seems. I don't think it matters much one way or the other.

[SCChris]

Re: Oven curing/insulation

I'm with Neil, on the insulation, as long as you can contain yourself and go slow with the curing. I seem to remember a few instances of clay flues cracking due to differences in temp. Insulating would seem to help to even things out but I've heard of anyone supporting this. As for the last brick I'd let the final brick sit till after the weekend and then put a lamp inside the oven for a few days. My thoughts are if the lamp keeps the oven something over the ambient temps and it moves air, which it will, it'll contribute to getting the water out. You should be in pretty good shape as far as dry goes if your humidity is anything like what I remember CU at Boulder Colorado to be during the winter. Again just go really slow on the curing and I think you'll avoid substancial cracking. Everyone seems to have some cracks show up. I think long low fires drives water out in a more even manner, but this is just my opinion.

Chris

[cecilB]

Re: Oven curing/insulation

Thanks Neil and Chris.
So Tim took down the arch and rebuilt it yesterday - I think he's just trying to stay busy without doing anything during this Easter break. But it does look a bit better.
It is very cool and dry here - no humidity yesterday or today, to speak of.

Should we smooth over the whole dome with mortar? It's been sitting all winter under plastic. The only new work on it, besides the arch, is the very top brick in the dome.

Thanks.
Cecelia

[SCChris]

Re: Oven curing/insulation

Cecelia,
My oven is contained in a small house that is packed with insulation. I'm going to have to defer to someone who has the igloo and has done the research on when you should apply mortar to the dome. As for the curing fire, give the outer arch a week or so to tighten up and cure the mortar before really starting your curing fires. In the dome I'd start with a old fashon 100w light and keep it on for a day. See where this takes the temps, interior and exterior. This bulb won't do much other than softly warm things up. After a day or so of this put an old fashon quartz work light 500w or so in the oven for a couple of days, mabey place some bricks in the inner arch to contain the heat. Again this won't push the temps up much, but since it runs for a couple of days, the whole dome structure is going to be over ambient temps and this is going to really help push the water out. I differed from the old school burn a piece of paper then the next day go a little bigger then... This method would have you run a burn a day and only run till you get to this temp and then let the oven cool. Some including myself feel that longer lower more gentle burns get the drying process moving and keep it moving without as much thermal shock. This method worked for me, but you need to educate yourself and make a choice. Whatever you choose, go slow, hopefully you'll only need to do this curring once.

One more thing, As your oven drys, the amount of fire to heat it will decrease. This supprised me a couple of times during the curing. I had a good slow steady temp increase and went to bed only to wake up and find the oven over what I had expected. My curing experience is documented in the oven curing forum.


Chris