Internal rendering

[brickie in oz]

Re: Internal rendering

we will wait and see. If its crap, then I will lay the fire blanket over the top

No need to wait and see as all the experienced oven builders on this forum will tell you to insulate, insulate, insulate.

[mrchipster]

Re: Internal rendering

Laku,

I have some Calcium Silicate board coming on monday if thats what you mean?
I am going to lay that in there, and then the fire bricks on top of that.

Im sure that will improve the base, in regard to the dome, well we will wait and see. If its crap, then I will lay the fire blanket over the top, and render it.

Great that you wil be putting cal sil under the floor.

Chip

[Laku]

Re: Internal rendering

That's the stuff you want.

Can't remember what're the insulating properties on Calcium Silicate board but I think the amount wanted was around 2" under the floor?
And you really do want to have a ceramic blanket(or some other insulation) on the dome. It will make the difference on getting the dome cleared or struggling get there.

[7.62]

Re: Internal rendering

Laku,

I have some Calcium Silicate board coming on monday if thats what you mean?
I am going to lay that in there, and then the fire bricks on top of that.

Im sure that will improve the base, in regard to the dome, well we will wait and see. If its crap, then I will lay the fire blanket over the top, and render it.

[Laku]

Re: Internal rendering

You could still try to salvage some of the performance. Lift the floor up insert insulation underneath it and put it back. Then insulate dome from outside, the performance should improve a lot.

[7.62]

Re: Internal rendering

Righto.

There are some design faults. They will not be repeated the second time. There is about $200 in materials invested, cost not important.

I have confidence, it may not be perfect, but I think it will be ok.

[david s]

Re: Internal rendering

If the sliding damper fails just use a firebrick tile placed over the top of the chimney. It can be easily adjusted to half or completely closed.

[brickie in oz]

Re: Internal rendering

There is a baffle system on there too, steel plate moved with a cable.

At pizza temps then the steel will distort and more than likely melt the cable.

Its a bad design unfortunately, pity you didnt find this forum earlier.
The good news is that for your next build you will be armed with all the knowledge to build an oven properly.

The other good news is, there will be a next time, Ive rebuilt my own oven after finding the "true" facts on oven building.

[brickie in oz]

Re: Internal rendering

I only need it to get hot enough to cook pizza.
.

Without insulation that may be a challenge.

[Laurentius]

Re: Internal rendering

Hi 7.62,

You stated that you build this for a friend. Does he have much money invested? I think that you should inform him of the down sides of this oven before he invests more into a project that might end up as a white elephant.

[brickie in oz]

Re: Internal rendering

Where did your briki wiki go? I used to read that....

I deleted it, I got sick of all and sundry stealing my content for their own websites, I did intend writing an ebook for Amazon but havent had the time.

[david s]

Re: Internal rendering

Too late to do a fix up now. My first oven had a central flue at the apex of the dome and in spite of members derisive opinions of this design it actually works pretty well. Ancient Roman kilns used this design. There are also some small domestic ovens at Pompeii that also used this design. Yes, you do lose some heat out the flue, but if the oven is small this is not really an issue. The two big advantages are that it draws beautifully, no smoke at start up because you are not trying to bend the flame. Secondly there is no entry to have to work past so accessibility and oven management are much easier.

[mrchipster]

Re: Internal rendering

Firebricks aren't insulation. And you really really want to have insulation or it will take a forest of wood to get in temp. And even then it will not perform good.

You are also going to be sucking heat into the slab out of the dome because the dome is sitting directly on the slab. There are a great number is serious issues with this oven design.

Chip

[Laku]

Re: Internal rendering

Firebricks aren't insulation. And you really really want to have insulation or it will take a forest of wood to get in temp. And even then it will not perform good.

[7.62]

Re: Internal rendering

Brickie, I dont need it to stay hot all day really, I only need it to get hot enough to cook pizza.

Where did your briki wiki go? I used to read that....