correct oven plans

[TapRackFire]

Hi all. I have everything ready for a my castable 42" oven except the design. I am unsure of how thick to make the walls, how tall to make the walls and various other questions about this cast. I plan on casting this thing ontop of my hearth and I only want to do it once.

Is there a good set of plans I could work from?

Thanks!!

Tap

[shuboyje]

Re: correct oven plans

In my opinion most of what you are asking depends on what you want from the oven. Thickness leads to mass. Mass takes time to heat, but stays hot longer. For general home use a couple of inches should be good. If you want to bake a bunch of bread you would want much more. Dome height depends on a few things. Is pizza your focus? If it is the dome height should ccodinate to the type of pizza you want to make. Lower for faster baked types and higher for longer bakes. If pizza isn't the main focus a true hemisphere will be easier to form and lead to a big door and therefore a better all purpose oven. Hope this helps a bit.

[GianniFocaccia]

Re: correct oven plans

Since you're going the cast route, you may want to consider modeling your dome after a commercial oven, which has more vertical walls and flatter ceilings. This configuration isn't recommended for brick domes, but provides for more internal volume for a given footprint.
John

[TapRackFire]

Re: correct oven plans

Thanks for the advice. I do not know the difference between a flatter dome or a true sphere shaped dome. I plan on baking all kinds of things with my WFO and had thought about casting the flatter designed oven in two parts using the refactory concrete about two inches thick (walls and dome) and then insulate well all around.

I was trying to find a build I could follow.

I looked at the specs for the Casa2G and Premio2G. I could not tell much differnce between the two's inner dimmensions.

Thanks for all the help. I hope to start casting soon. The hearth is ready and waiting for the the oven.

[Lburou]

Re: correct oven plans

This thread gives you what you are looking for.

P.S. Three inches of refractory material will take a long time to heat...But it has the potential to store a LOT of heat for extended baking after pizza.

[TapRackFire]

Re: correct oven plans

I love the help and advice. Keep it comin. Lburou, I sent you a PM. I am going to try to copy yours if possible. I have several questions.

Tap

[sonomacast]

Re: correct oven plans

I basically used this as my guide http://www.fornobravo.com/residentia...emio2g110.html

But followes rules I found on the internet,
the height of the interior dome is 90% of the radius of the oven floor?
The Door opening height is 63% of the dome height?
The area of the flue is 10% of the area of the door opening?
The ideal door is 22" wide at the dome?
The flue should be 10% (area) of the area of the doorway
the ideal floor is 2 1/2" thick?

My Oven
The Oven floor is 1050mm in diameter (41”)
The dome height is 472mm (18.5”)
The doorway is a semicircle 558mm (22”) wide 297mm (11.6”) High (225.2"square)
The final Flue is 8” in Diameter (50” square)

After more studying i have now deduced that 40.3% of the diameter is the average dome height when it comes to commercially sold ovens. i found this file in the forums Forno Bravo Forum: The Wood-Fired Oven Community - The Pizza Oven Installation and Cooking Community

nHope it helps

[TapRackFire]

Re: correct oven plans

I finally got my castable material. $32.00 a bag. I bought 12 bags. I will see how far it goes. I plan on pouring my walls about 2.25 inches thick. I also got my stainless steel needles. These "needles" are alot bigger than I had imagined. These are about as long as a needle, but they are wavy and aabout an 1/8" wide. My buddy said to make sure I were plenty of protection on my eyes, hands and arms when I use them.

I did have a concern about the size of my landing. As I build the plug for the landing it seemed to get wider and deeper of my orginal 7.25" deep design. It grew to over 9" inches deep. I cut it down and now have it to 8" inches deep. Is that too deep? I still have to add an 8" flue and figured this would be a good match. any suggestions?

Tap

[david s]

Re: correct oven plans

"I also got my stainless steel needles. These "needles" are alot bigger than I had imagined. These are about as long as a needle, but they are wavy and aabout an 1/8" wide."

These sound suspiciously like the first lot I got. Turned out they were not stainless steel at all, they were normal steel reinforcing fibres. Try leaving some outside in a saucer of water and see if they rust. Don't bother doing a magnet test on them as not all stainless is non magnetic. My genuine stainless steel needles are magnetic, they are about an inch long and are round like a needle. The other test is their price. The genuine stainless steel needles (correctly known as melt extract fibres) are horrendously expensive. Once freight goes on I pay around $20/kilogram

[TapRackFire]

Re: correct oven plans

I just looked at my "needles" they are called "850 steel and multifilament synthetic blend." I don't think they will be stainless steel. But I do have 48 pounds of this stuff. Could I use them?

[david s]

Re: correct oven plans

I'm really not sure. Because of the heat there would be accelerated corrosion and that could create more problems which could weaken the refractory way more than the strength that they would give it. I believe this is the reason that stainless steel is specified. If it were me I'd opt for no reinforcing if I couldn't get the correct stainless steel fibres. I didn't use any reinforcing in the mix for my cast mobile oven and the dome is in good condition despite plenty of abuse.

[david s]

Re: correct oven plans

I use Novomesh 950, for reinforced concrete, but they are two types of plastic fibres. One is really fine for compressive strength and the other are thicker and longer for tensile strength. Our local council use them for concrete paths. Way easier than steel reo.

[david s]

Re: correct oven plans

That would be correct, but if you order stainless steel melt extract fibres then that's what you should get.

[david s]

Re: correct oven plans

Yes they are designed for paths. Our council abandoned the use of steel mesh a few years ago and use these instead. They are obtained from concrete engineering supplies.
Attached are photos of steel fibres like you got and the resulting damage the rust has done where they are close to the surface.

[david s]

Re: correct oven plans

Oops photos didn't attach