Steel Dome Oven

[Crashdot]

I’m building a ‘lite’ version of this design and this excellent thread has answered many of my questions, as well as inspiring some design ideas. I posted some info and questions a couple months ago (https://community.fornobravo.com/for...ign#post438075) but got limited response - I guess everyone was hanging out here!

The big difference in my design is that the metal is just a thin liner. From what I gather from all these posts I think it should work out. I expect to build the dome this month. I’ll post results and pictures in the new thread.
It’s nice to see that others are also on the multi-year build plan. I will have my wife read these next time she complains about how long it is taking me!

many thanks to all the contributors.

[aidanphilipson]

Wiley you are an inspiration. I am building a small batch of steel-based ovens this spring, with a view to launching my pizza business in the next couple of months. I stumbled across this and the info has been great. Thank you. Aidan

[david s]

Wiley,

long time no hear, glad to hear the oven is functioning well. Goes to prove there’s more than one way to skin a cat.

[Wiley]

Hello good people,
Been a long time since I circled back thru here and saw these last posts with questions about how my WFO is holding up. Attached are a couple of photos.
I painted the oven this year and (excepting cleaning) that is all the maintenance the WFO has required since it was last painted 12 years ago. The oven still fires quickly and holds heat well.
Only change I would make (and this is not large enough for me to do) is to use a larger in diameter chimney : instead of a six inch diameter I would go with 8 inches.
Hope this helps,
Wiley

[Mike Potts]

after alot of lurking and reading...i am inspired! this seems like the way i want to build my oven as well. thanks for the great info and write up.

[ColSmoke]

Hey Wiley,
I am beginning to build my own steel dome oven from a propane tank end and wanted to see how yours is holding up over the years. Thanks for your previously shared advice and inspiration.

Casey

[buckeyebreadman]

Re: Steel Dome Oven

If there's a slower build I don't want to know about it.
I actually opted for 2" of insulation board on top of 4" of vermicrete.
I'll now add a layer just like Wiley did. The thinner Firebrick and the usual thicker ones (2 1/4"?) Going on Three years and that's where I sit. Should get the dome on this spring. I'll update then.
The soapstone was just too expensive.

[nmich_mason]

Re: Steel Dome Oven

How did it turn out?

[Wiley]

Re: Steel Dome Oven

Buckeyebreadman,
Using a layer of soapstone where I used a thin layer of firebricks should work fine. The thinner layer of firebricks was to provide a stronger more wear resistant surface for the steel dome to sit upon rather than simply sitting the dome upon soft vermicrete. I was concerned as the steel dome expands and contracts with each firing that it would slowly wear into it. This could potentially cause all sorts of problems with intimate contact (think heat transfer) from the steel dome to the refractory heat reservoir overlaying it.

Soapstone is also known as talc and when ground to a fine powder is talcum powder. In this case I would expect the soapstone (although softer than a firebrick) would act as a self lubricating surface. It should work very well.

Bests,
Wiley

[buckeyebreadman]

Re: Steel Dome Oven

Wiley, I hope you're still up on this page. I'm all the way up to the insulating layer (only two years in the making here) and was wondering.....you have, in post #41 a thinner layer of firebrick and then the oven floor on top of that. For the purpose of keeping the floor level, would a layer of soapstone suffice for that thinner firebrick layer? I'm not sure my vermiculite insulating layer is perfectly level....

[Wiley]

Re: Steel Dome Oven

Ellisco1,

Due to a computer virus several years back I lost a great many of the photos I took during construction. A good reason to back up important files which actually I did, however, I have miss-placed the dvd with the backed up photos. So it is as if they were same as lost except that there is a hope that someday the disc will turn up :-|

However, in answering your question, if one looks closely at this photo:
http://www.fornobravo.com/forum/atta...-side-view.jpg
On the insulation layer about one foot up from the bottom, one can see the indent of a line that originally ran all the way around the WFO. This was from a piece of kevlar measuring tape I re-purposed.* Now there are many ways to cover a dome with insulation. Since my kaowool was about 4 ft wide, the method I selected was to wrap the insulation around the dome so that it was standing on edge forming a sort of cylinder. The Kevlar tape held it against the dome and allowed the cylinder to stand upright while I cut slits down from the top. These slits allowed me to fold the insulation down onto the dome and allowed the extra material to lie over the adjacent piece. Extra pieces were laid on and over the top and held the whole insulation fold-up/layup together. There are two layers done this way and the folds are laid out so the overall thickness of insulation is fairly uniform and increases as one measures up the outside of the dome.

I originally planned on leaving the kevlar tape in place until I placed the birdcage and started filling the loose vermiculite. At that point I had planned to cut the tape and tuck it in and forget about it, (and it is in place around the inner layer). However, in placing the birdcage it became necessary to release the kevlar tape around the outer layer. When I released it I found that the insulation had assumed the desired shape and had no inclination to either slide off or fall away from the dome. The top was held by the pieces laid across which kept it from sliding. And it would appear that in the time between placing the insulation and the birdcage the insulation had formed to the dome and stuck/adhered a bit to the inner layer of insulation. Since it was holding I saw no need to replace it and so didn't. Once the space between the insulation and the birdcage was filled with loose vermiculite, it held the insulation in place and in contact with the refractory (or at least the outer shell never has gotten hot so one would assume it still is holding it in place).

Kelvar tape is not that uncommon, it's also used as pull rope to pull wire thru conduit. But as it turned out I really don't think it is needed in the method I used. One would still need to hold the layer during assembly but that could be done with wire and after the second layer is placed and allowed to settle in you could carefully cut one end and pull out the inner wire. The outer wire could be left or removed.

Hope this helps,

Wiley


*It was originally a measuring tape that had been damaged in it's first few feet, someone had balled the whole mess up and tossed it. I found it along side the road on one of my walks. I knew what it was and that kevlar is quite heat resistant (check the material used in a OveGlove and you will see it's made in part of kevlar) and being a scrounge at heart, I gladly picked it up. Once you see it it is easy to identify, sort of golden color, very strong and heat resistant.

[Ellisco1]

Re: Steel Dome Oven

Wiley,
Your build thread is an inspiration and I am starting on my own. One question , how did you get the Kaowool to stay in place while you were working on the cage? I was thinking of sticking some wires into the wet mortar then punching those through the insulation and bending them over but then I have never done this before.

[waynespizzaworld]

Re: Steel Dome Oven

Thanks Wiley, good to know. I am a recycle yard shopper myself. Sounds like a good deal on the tires, way to go. The recycle yard I frequent rarely has any steel, they seem to mostly have aluminum. Looks like you found the components for your build at a good time. Love your oven by the way, very clever.

The photo attached is my from my last visit to the recycle yard. The guy that sold me this real, figures it is a Data real of some kind. I ran a shaft through it mounted to a 10 inch stand with a wheel bearing in between for some nice spinning action and faced the center hub with some copper. I use it as a giant Lazy Susan for pizza toppings. 4 bigger bowls and 4 smaller to hold grilled veggies, cheese, flour, corn meal etc. Works real nice and I only paid 10 dollars for it. Feels good to get a bargain and then have some fun turning it into something else! When its not dispensing food I just hang it on the wall as decor.

[Wiley]

Re: Steel Dome Oven

Hi Wayne,
I do not know all the sizes these old tanks came in. But right now finding any suitable tank is going to be problematic. The problem seems to be the high price of scrap steel. The man from whom I traded for my tanks used to have several sitting in his yard. The story I got was that he had a contract with some scrap yards in California. Seems they were unwilling to cut them up for fear or liability. So he had a fairly steady stream of tanks which he cut in half and sold for backyard BBQs and such. That was 4 years ago. A few months back I chanced to stop by his yard in search of a set of used tires for my utility trailer. His yard was almost cleared of all the scrap metal, but there was a goodly sized hill of used tires. He told me that the price of scrap was so high it made sense to simply take the wheels off and crush the cars and send them to Seattle. From there they went to Korea or China or ? I got my tires (a nice almost new set of heavy duty tires for travel trailers and the cost was all of $5 each). Seems tires are hard to recycle and cost him money to get rid of.

I expect the situation to be similar anywhere along the West Coast, but you might try calling scrap metal dealers in Vancouver and see what they can do for you.

Bests,
Wiley

[waynespizzaworld]

Re: Steel Dome Oven

Wiley do you know if these old spherical tanks can be found in both a 42" and a 46"? The reason I am asking about this size is I am thinking of using the two sizes of tanks for a two part mold on a castable project. 44" and 48" would also work I guess. Also 40" and 44" in a pinch. The idea is to have a mold that would give me room for a 2" thick cast dome.
Also would you have any ideas for locating one of these beasts. I am in the Vancouver Canada area but could travel state side to pick up if I could buy two different sized hemispheres to accommodate this project.

Thanks Wayne