First rough draft oven design - Want comments

[clofgreen]

I'm totally new to this forum as well as the idea of building an oven. I hope people can give me some advice. I'm building the oven for just my wife and I. We'll bake bread twice a month and an occassional pizza, maybe a roast, or corn on the cob, etc. I'm building it mainly as a failsafe against a long term power outage so want to build it on the cheap.

I happened to find a great deal (I think) on high quality firebricks. They were destined to go inside some ovens at a steel mill but they changed their minds. Here are the bricks I got. The small ones were 35 cents apiece, the large ones were 50 cents apiece and the arched one is a dollar. The small piece has 60% alumina, the others 45%. Is this too high?



I thought I'd make a 3 foot by 3 foot oven (interior dimensions). I'll use the larger bricks for the hearth. The arched pieces give me a 10.5 inch high by 15.5 inch wide doorway. 10.5 is exactly 63% of the interior dome height.



I don't own a tile saw so will be borrowing a neighbors. Since I don't want to do a bunch of cuts, I came up with a domical vault design that (I think) will combine the advantages of a dome with the simple construction of a vault. At least this is the idea. Since the vault brick pieces are tapered, I can get by with a very thin joint except where I want it to curve more to give me a slightly lower ceiling. Also, I'm not sure if 3 inches of brick is enough for hearth and dome. I guess I could add an inch or so of refractory conc if needed.




I'll frame the opening with a stack of the smaller bricks that match the height of the arched piece. I'll fabricate a vent over that.



I'd really appreciate some feeback since I'd like to start on this right away. Thanks for a really good forum.

Craig

[Tscarborough]

Re: First rough draft oven design - Want comments

It will certainly work and be a piece of art, but it is shooting flies with a 12 gauge.

[dmun]

Re: First rough draft oven design - Want comments

I'm not convinced that it's any less cutting than a standard pompeii, unless you try for the perfect fit, but it looks cook and I wish you luck. I'm just a tad concerned about the four giant running seams going from top to bottom. What mortar are you planning to use?

[david s]

Re: First rough draft oven design - Want comments

Can you stagger those bricks on the corner seams so they tie into the corners better?

[Mike D]

Re: First rough draft oven design - Want comments

Everyone says a round oven works better. Read the section in the plans why. That design doesn't look any easier than a dome anyway. (kind of a fun idea though)

-good luck

Mike

[clofgreen]

Re: First rough draft oven design - Want comments

Wow, these are great comments.

Tscarborough: Shooting flies with a 12 gauge? Could you elaborate? I shot a sparrow once with a 20 gauge and a squirl with a 30-30. Both created a bloody mess. Is that what you're saying, this is going to be a bloody mess?

dmun: Really? I thought you had to cut every brick in half for the dome. Also, I've read here and elsewhere that the large mortar joints were a problem. In the 3D model most of the joints were all quite thin and the number of cuts were quite low. Hmm. But you are the master jedi oven builder so I better go back and count them again.

Regarding the seams: In some historic Domical arches they run a supporting rib up the seam but it hasn't been shown to add that much more stability. These arches by themselves are very stable, or so the history books say. But they were a lot better craftsmen than I'll ever be. This will be my first ever masonry project. I haven't done too much research on mortar yet but hope to use whatever will be the strongest in a thin joint. Suggestions would be very helpful.

David S: I did a 3D study yesterday and yes, I think I will be able to tie the corners.

Mike D: I've read the section regarding dome vs. vault several times and frankly I'm not convinced that for general post-fire cooking (which will make up the bulk of my cooking) that there is much difference. Unless I find someone who has built the Domical arch oven and tells me it flat out doesn't work I'll proceed with this design, if nothing else just to add to the knowlege base of what works and what doesn't.

Craig

[Tman1]

Re: First rough draft oven design - Want comments

I think Tscarborough's comments mean that while it will work, it's way overkill (or at least that's what I was thinking when I read it). An Allan Scott style vault would give you plenty of heat and have far less cutting than what your displaying here. A domed oven might have more cuts, but they would be far simpler (angled, but straight) whereas the cuts for this type of dome would be a double angle which I don't think would be easier, and I don't think you've save as much as you think.

But it'll be interesting if you try- just make sure you post pics of the build to inform us all.

[Faith In Virginia]

Re: First rough draft oven design - Want comments

First off shooting flies with a shotgun ='s over kill

I think you have a cool looking oven and you may reduce your cuts with this design but all your corners will be a compound cut that will require great precision. As far as heating and cooking I don't think you will notice a difference from other ovens as long as you follow the normal ratios for door height to dome height and such. I do have issue with the structure as a standalone structure. So I believe you will have structural failure. I believe with the heating and cooling of that oven each side will have a tendency to snap in the middle even with lacing the corners. If you are really wanting your oven like this I would suggest to buttress the lower half of your sides with 3 or 4" of concrete. Refer to the Allen Scott design of the vault oven.

So in the end no matter what your final design is after insulation and a protective stucco the coolness of the shape would be lost on the exterior and not many people stick their heads inside the oven to look at the interior. Most people look at the food coming from opening.

Just my thoughts , Faith

[Tscarborough]

Re: First rough draft oven design - Want comments

A simple low dome arch will work just as well, if not better and will require NO cuts (well, a few halves if you make it running bond).

[Tscarborough]

Re: First rough draft oven design - Want comments

But if you want to do it just to do it, I say go for it. It is structurally sound, even with the heating and contracting of an oven. It will require more buttressing than any other arch though. After all, I built my oven because I wanted to build an arch, not the other way around, so I understand where you are coming from.

[dmun]

Re: First rough draft oven design - Want comments

I think I will be able to tie the corners.

If you can do this, I say go for it. I think it's a way cool design.

[Faith In Virginia]

Re: First rough draft oven design - Want comments

Did some more thinking about this... To lace those corners would be a nightmare for even an experienced oven builder.

[Tscarborough]

Re: First rough draft oven design - Want comments

There is no way or need to tooth the corners.

[clofgreen]

Re: First rough draft oven design - Want comments

Did some more thinking about this... To lace those corners would be a nightmare for even an experienced oven builder.

Yeah, just analyzed the 3D model. Nightmare to say the least. Lots of small detailed cuts. I'm leaning toward a vault design unless Tscarborough can convince me that what the others have said about the structural integrity is wrong.

Some have said that this is a cool design. I don't want cool. I want easy to build, few cuts, low cost and cooked bread. I'm trying the best I can to use recycled materials. My conc. blocks are 50 cents (they bought one pallet too many), the tapered firebricks were 35 cents, the large ones were 50 cents (from a steel mill). I found some cheap metal studs at a construction site. Do you see a pattern here?

I just talked to a local guy who built a vault oven based on Tscarborough's construction photos using similar bricks he got at the steel mill here. He is very happy with his oven saying he fed the entire high school soccer team pizza cooked in his vault. Maybe I'll chicken out and go with a vault. Will be a whole lot easier.

Craig

[Tscarborough]

Re: First rough draft oven design - Want comments

"I don't want cool. I want easy to build, few cuts, low cost and cooked bread. "

Then run the hell away from your design, and do a simple low vault.