51" Oven in France

[Les]

Re: 51" Oven in France

Nah, that should be fine. A lot of us... ok, some of us, didn't taper the bricks at all, or only towards the top of the dome. Its more of an esthetic thing.

Frances - your inside fire brick could fall to the ground and you have no worries. You could put a Monet or Picasso in place of the door and charge people for the experience. Your dome is a piece of art!

Les...

[MAVANO]

Re: 51" Oven in France

Did mine 48 inch round, hight of dome 24 inch, worked out well, it takes more wood to reach pizza temp. but once there ,2min pizza and baking bread at 400-500f. is great heat retention with a door of course, the floor can be ground down with another brick if its not that bad

[Frances]

Re: 51" Oven in France

Nah, that should be fine. A lot of us... ok, some of us, didn't taper the bricks at all, or only towards the top of the dome. Its more of an esthetic thing.

[exipnos]

Re: 51" Oven in France

I have a quick question. I was planning on tapering the bricks for a closer fit but then my father is not thinking its necessary. Now we are at the third row and I can already see the inverted ?Vee? between adjacent bricks. Since my old man tends to do what ever he wants while I'm not there working with him, I wonder what will happen if you just continue without tapering the bricks. Is it only esthetic or will it have an impact in stability or longevity of oven?

[exipnos]

Re: 51" Oven in France

Thanks for the tips. I think I'll try the belt sander or orbital sander idea for the worst spots and then wait to see how that works out. If needed I can always put in the larger tiles at a later stage if it really bothers me.

Cheers,

Kosta

[Les]

Re: 51" Oven in France

First choice is to grind down the uneven parts. Not sure exactly how to do that? Sanding it down or what tool?

Kosta,

I used a belt sander to take off the edges - it would take quite a lot of work to do the whole floor. You just want to get it to where you don't catch the edge of your peel.

Les...

[dmun]

Re: 51" Oven in France

The floor surface show that there are a few small gaps where again due to the shape of brick they don't touch. Is it a good idea to fill the gap?

An excellent material for filling those pesky floor gaps is wood ash. Leave them be. You may want to temporarily cover the floor with a cardboard cutout to keep your floor clean as you work on the dome.

[exipnos]

Re: 51" Oven in France

Hi again,

Here are some shots from today's progress. Lost a half day in thinking about dome shape, preparation and tool creation. I created a cutout of my dome shape. I decided to go for 20" height or 50cm exact.

Then my father and I started laying the first bricks. Using the cutout the first bricks went on all right following the curve. But then my father decided that he knows better and that he can eye the placement. Over a quarter of the circle is now off about 1cm from the curve. Oh well I hope it will be okay anyway.

Pictures attached. Bricks follow the curve very closely but on the picture is looks that there is quite a few gaps. The bricks edges are sometimes not straight and that shows in the picture. I hope its good enought.

The floor surface show that there are a few small gaps where again due to the shape of brick they don't touch. Is it a good idea to fill the gap? With mortar?

Thanks for you time.

By the way is there a way to change the title of the thread from 51 to 47" for accuracy?

[dmun]

Re: 51" Oven in France

It's ok to grind off some high spots but don't go crazy and try to abrasive smooth the whole floor: the exterior of the brick is considerably harder than the interior, you want your floor to last.

[Frances]

Re: 51" Oven in France

I don't know what others think, but if the floor thickness is the same as the dome thickness, it should be ok... could even be an advantage.

With a big dome you'll be looking at a relatively long heat up time anyway, and I would think that 10 cm doesn't constitute a heat sink. But I may be entirely wrong here, so wait until you have some more opinions...

[Justin]

Re: 51" Oven in France

Thats some bad news Kosta. how uneven is it? do you have a photo? im sure some people on here have come across this problem before and have some good advice. I'd be inclined to try grinding it down because as you say otherwise you will probably have too much thermal mass and it could be v.hard laying tiles over uneven brick. in any case goodluck!

[exipnos]

Re: 51" Oven in France

Hi again,

Justin - I think my calculations for the dome was correct and I could fit the dome circle plus the insulation into my pad. But I now realize that I did not really take into consideration the vent/oven landing space. After drawing up the 51" circle I now see that it does not leave enough space for that. Thank you for pointing that out

I have now downsized my oven to a 120cm or 47" internal cooking surface.

Yesterday my father and I started by putting down 10cm AAC block as the insulation under the oven. We then proceeded to put down the 84 or so full size bricks as the cooking floor. The brick dimensions here are 11m by 22 cm by 7cm thickness. It was harder then I thought! The bricks are not exactly the same dimensions and there is sometime a small variance in either dimension.

Even though I was planning on just using sand as the base (I did not search for fireclay) and special refractory mortar (good upto 1200 degree Celsius) for the dome. In the heat of the moment I somehow forgot all my plans and mixed and used a sand/mortar mixture. The cooking floor ended up mostly even but in some spots to uneven for my liking. I have not checked this morning but I believe the bricks are now mortared in and cant not be taken out. I now have two ways to proceed. First choice is to grind down the uneven parts. Not sure exactly how to do that? Sanding it down or what tool?

Another option is that my supply store had special refractory tile 30cm by 30 cm. I was going to use that initially but thought the thickness of 3cm was to little. So option number two would be to install this large tile on top of my somewhat uneven floor surface. But that worries me that I would then have to much thermal mass in the floor. Total thickness will then be 10cm or about 4".

Is that to much thermal mass?

Today we will start on the dome construction. Before starting I'll play around with the dome height but I hope to stay as close to 20in as possible. Wish me luck I think I need it.

Cheers,

Kosta

[Justin]

Re: 51" Oven in France

Kosta, my pad is 1.9m x 1.7m, and by my calculations i can only fit up to a max 42" internal diameter oven on that slab, while i am building mine to be about 40" (1m). remember you need to allow for 2x the: brick width, insulation, and final render. It adds up! Please triple check these figures before going ahead otherwise you may get a suprise when theres no room for insualtion.
Also if each pizza takes 2-3 minutes you can definately cook a whole heap of pizza in a short time even if youre doing 2 pizzas at a time. 10 Pizzas in 15 minutes.. do you really need more than that? Anyways, just food for thought, not trying to discourage you. To be honest i would love to see a 50" oven!

[exipnos]

Re: 51" Oven in France

6 pizza's at a time, you are my new hero! (these were being cooked in 120 seconds or less, right?)

Les...

Thanks, with 6 pizzas you have to hustle both to get them ready fast before the stick to the the bench and you have to work fast in the oven. I don't actually remember if it was 120 sec but somewhere close to that Okay 6 pizzas at a time in only really necessary in a commercial setting and I rather just deal with maybe 3-4 at home

[exipnos]

Re: 51" Oven in France

The other point I'm struggling with is the "cosmetics" of the oven. I like the look of the spasso pizza oven (in my other message below) and would like to do something similar. But that style calls for a chimney that is not in the mouth of the oven but slightly recessed towards the middle.

I saw a construction at mha-net.org MHA News - 2006 Meeting - Backyard Oven with Peter Moore towards the bottom that shows details of the idea. Any idea how big the smoke channel needs to be? Any pitfalls?

Regards,
Kosta