Oven Drawings and Measures

[sanlucas]

Hi, I'm building my first oven, I was decided to build it from castable cement but now I'm not so sure. I made some drawing with the oven and metal stand measures so you can give me your opinion, all the measures were based on fire bricks and the metal stand will be made of 2" square tube

[Les]

Re: Oven Drawings and Measures

What exactly is your concern? Personally, I would add a little more vertical support as over kill. All (most) the weight is on the perimeter. (I know you know that)

Les...

[azpizzanut]

Re: Oven Drawings and Measures

Hello sanlucas,

If you use refractory cement to cast a 42" dome it will be less outside diameter than with fire bricks, assuming you cast it 3 inches thick. The outside diameter will be reduced by 3 inches. Cast refractory is heavy. Don't forget you may need to move the dome or dome parts one or more times to get it into place from where it is cast.

Cheers,

[dmun]

Re: Oven Drawings and Measures

A few comments. Three inches of vermiculite under the floor isn't enough. You need at least four. A two inch support slab of concrete isn't thick enough to reinforce: your rebar should be at least an inch in. Three and a half is the minimum recommended, four is better. If weight is a concern, then go with a metal support layer, since you're at the metal dealer anyway. I can't speak to the metal stand, but my impression is that it's gonna wiggle some without some diagonal bracing. I could easily be wrong on that.

Two inch thick stucco dome cover? seems like overkill to me.

An eight inch entry isn't enough to get a vent out of. I'd make it a bit deeper.

Nice drawing, by the way. Seems like you're really thinking this out.

[Les]

Re: Oven Drawings and Measures

David, how were you able to get the numbers from the drawings? I didn't have near enough resolution to read them (other then the obvious)

[dmun]

Re: Oven Drawings and Measures

David, how were you able to get the numbers from the drawings?

They're clearly visible on my monitor.

[sanlucas]

Re: Oven Drawings and Measures

Thanks for the suggestion. Dmun I like your idea of the metal support layer (do you mean a thick metal sheet? how thick do you recomend?, I tought that the 2" concrete slab would work beacuse I saw this http://www.fornobravo.com/forum/f6/f...tand-1046.html and it says that "it can be filled with 2" concrete/rebar, 2" vermiculite, then topped with Super Isol board" so because it has the square pipe across the stand supporting the weight, I also saw a thread in which the guy installed concrete paver under the insulation layer and it seem to be working for him.
Also how long should I make the entry?

[Les]

Re: Oven Drawings and Measures

They're clearly visible on my monitor.

Wow - I just viewed it with my system at work and I can read it. Obviousy my laptop's graphics card is junk.

Thanks,

Les...

[dmun]

Re: Oven Drawings and Measures

the guy installed concrete paver under the insulation layer

Well, pavers. Hmmm. It's supposed to support the oven, not to need support its self.

Metal underlayments have been done successfully. If it were me, I'd look into what I could get cheap. The junkyard should offer up some suggestions, maybe diamond plate stair treads that could be welded together? really, anything that will offer some support.

I read your link:

You can either fill it with a 1" layer of concrete/rebar, then 3" vermiculite concrete, or with 2" concrete/rebar, 2" vermiculite, the topped with Super Isol board. Use concrete board inside the tray to form when you are pouring, and leave it is place when you are done.

Frankly, I don't know what James is talking about here. A one inch layer of concrete and rebar? I would think that would crack, if not fracture, the first time you bumped into it. Now mind you, I've never seen one of the FB metal stands. The tray might be really heavy gage, and the concrete just serves to rigidify it.

The depth of the entry? Remember you have to put some kind of chimney on top of it, so it has to be big enough to accommodate it. I'd suggest looking at some pictures, like this one on the front page today:



You can get an idea of the size of any brick structure by counting bricks. A firebrick is nine inches long and four and a half wide, and two and a half thick.

[sanlucas]

Re: Oven Drawings and Measures

Dmun this is the thread I was talking about http://www.fornobravo.com/forum/f8/d...oven-6774.html