Dome on floor or on FB around floor?

[Mr. I]

I am ready to build the floor for my Pompeii style oven. Is it better to have the dome on the oven floor or around it? I've seen both and the only benefit to around it seems to be availability to eplace floor bricks. Also, if I do build it around the floor it sounds like an 1/8" gap is required. Filled with a piece of cardboard?
Mike

[UtahBeehiver]

Need a little more info on build to comment, is the oven being enclosed or is it an exposed to the element Pompeii.

[slschoming]

I had the same questions when starting my build and in the end decided to build my floor inside the dome. I cut my floor bricks and then as I was laying the dome around them I just left strips of corrugated cardboard between the floor and the dome. The cardboard is still there but will burn up as soon as I start firing my oven. I think if I ever have to replace one of my edge floor bricks it will still be pretty difficult to remove, but it will be a lot easier than if it was under the dome.

I think whichever route you take, the key is to have the floor and dome as separate pieces (not mortared together) so they can expand/contract separately.

I can't find the post now, but I read that if you build the dome on top of the floor you should still put down cardboard (flat, not corrugated) between the floor and the dome bricks. This cardboard will burn up during curing fires or shortly after, but will serve as a barrier during your build to prevent the dome and the floor from adhering to one another.

[Mr. I]

I plan on leaving it exposed. Typical dome finished with heat stop, then stucco, then paint. If I housed it would that make a difference? I live in Ohio and winters can be rough. Is there an issue using the oven in the winter? I'm sure enclosing it would help.
The build I am going for is 39" floor, 3" FB, 2" blanket and then heat stop.

[Mr. I]

Thank you Seth.

[UtahBeehiver]

If you were enclosing then you could lay the dome bricks on top of the floor and the floor bricks would not need as precise of trimming, just leave proud vs an open to the element oven. I have only seen one or two instances where removal of the floor bricks were required so it is a rarity. Cutting the floor to fit inside is time consuming, I did it, but if I were to do again I would place dome on floor vs floor in dome and spend my time resource elsewhere. Why are you installing "Heat Stop" over blanket?. Pretty expensive blanket coating, better off with v or pcete then stucco coats. 2" Ceramic Blanket is bare min unless you add p or vcrete layer over blanket. I disagree about placing cardboard between dome and floor when placing dome on floor, it is only needed when floor is inside dome.

[Mr. I]

Thank you, that makes perfect sense! Yes, I will put "vcrete" on top of the blanket. This forum is awesome! I'm so glad I found it 5 years ago but disappointed am just building now.

Regards
Mike

[UtahBeehiver]

Better late than never. Do be sure to reference and search the forum for the best of the best ideas and construction. There is no one stop shop so you need to poke around and make an informed decision on what works for you. Don't wing it then ask what to do after the fact, by then it is too difficult to correct. If you have not do so yet, down load the e-plans from Forno Bravo, they are only 3 bucks and a good baseline, then peruse the sticky under the Newbie Section called "treasure archives", here are links for some of the more documented builds.

[Mr. I]

Hi,

I am getting ready to set my floor. The plans call for a "Paste" layer down under the floor made from Sand, Fire clay and water. I will have Ceramic Fiber Board under the bricks. Should I put the paste under or on top of the CFB? Do I put any heat stop mortar around the floor?

Thank you,

Mike

[slschoming]

I did not use this paste layer. This is just to get a nice level surface for your firebrick floor. My CF board was already level and I wasn't going to be able to make it any better. If you find that you need it, you would put it on top of the CF board.

[david s]

Because the insulation board is so water absorbent a wet mix will dry as soon as you place it, making setting the floor bricks very difficult. Some builders coat the surface of it with some kind of sealer, or alternatively place the sand/clay mix dry and wriggle the bricks into it. This has the advantage of making any brick removal down the track a lot easier.

[UtahBeehiver]

You only need to use fire clay sand mix if you CaSi board is way out of level.

[Mr. I]

Thank you!

[luiscuomo]

Hi Utahbeehiver, Im planning the dome of my 36 ´´ oven (High dome), and Id like to do the 1st course with soldiers. But I dont understand how should I use the IT, since the upper edge of the soldiers is at a longer distance than the 18´´ radius.
I can adjust the radius of de IT but the the dome higth woud be taller...

Thanks. Luis

[UtahBeehiver]

Any particular reason for soldiers? Are you wanting to do full height soldiers, this set set up may require buttressing of soldiers on outside. You use the IT the same as full hemisphere sphere, pivot point right at floor level is the very best point.