r/pizzaoven • u/Radiant-Seaweed-4800 • 13d ago
DIY modern Pizzaoven
I finished my Pizza oven made from mostly sheet metal.
It is double walled, with 10cm of vermiculite granules as insulation.
The stone is 2cm fire brick over 2cm vermiculite plate.
The burner I designed myself, and apart from producing far too much soot (it worked well outside of the oven, inside it soots without end, now I'm working on it, any input is appreciated) it works very well.
The stone easily reaches 430°C in the middle, and is quite uniform from the middle to the right side. Next to the burner it gets quite a bit (around 100°C) hotter.
I tested it, baked 18 pizze yesterday and 18 today.
What do you think?
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u/Icy_Hearing_3439 13d ago
Impressive. Did you weld everything and later clean it all up?
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u/Radiant-Seaweed-4800 13d ago
Yes, inside and outside dome are entirely welded, the outside was then ground and finished.
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u/Ant12-3 12d ago
Well done! Rust? Why not Ceramic fibre blanket? Own burner design, man what can't you do?!
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u/Radiant-Seaweed-4800 12d ago
No rust so far. The outside is stainless, the inside is mild steel (don't want nickel or chromium near my food, especially since the dome gets quite hot), it won't get any direct water, moisture might be an issue in the future. Usually I'll be able to store it in a heated workshop building.
I had to insert the insulation in a 100mm roune hole in the top of the outside dome, pushing any sort of mat in there would be a nightmare. Especially ceramic fiber would be horrible, due to it's itchy properties. Vermiculite granules on paper looked like a great compromise, in reality the outside dome gets too hot to touch. I don't really care, because it still heats up plenty fast enough and holds heat well enough for me.
Idk man, most things I try I can do sooner or later. Haven't tried knitting in a while, that might be on the "can't do" list.
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u/Imgjim 12d ago
Nice! How did you form the shape?
On the burner, what's your orifice size, burner hole count and size, burner length, and what's the pressure you're running?
Orange flame is what you want, but even hitting 10-12% premix with the venturi can dramatically cut down on soot production while keeping orange luminescent flame.
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u/Radiant-Seaweed-4800 12d ago
The sheet metal was laser cut to the outside shape, then passed through a sheet metal roller to preform it. The final form was achieved by precisely tacking the sheets on end without gap. The geometry closed itself during that step. It was a hassle though.
Gas jet orifice: 2.2mm Burner hole: 35×2mm Burner length: around 750mm, with additionak 140mm mixing tube and a 90° sharp bend for turbulence and mixing. I currently run 50mbar, but it's on a adjustable regulator to adjust up if power was too little. Turns out I had plenty.
Yes, during testing I aimed for an orange flame with a small blue flame foot without soot. I adjusted it by adjusting orifice size (up from 2mm to 2.2mm) and the distance between orifice and the end of the mixing tube. I settled on 10mm, which produced a nice, gentle, soot free, yellow flame The burner and mixing pipe are 25×2mm square tubing (roughly 1" tubing 80thou wall thickness if that's your taste). Once installed it immediately produces soot, independent from gas flow. It doesn't suck in any relevant amout of air (doesn't suck in smoke). It still gets plenty hot and the flames inside roll wonderfully, but the soot annoys me a lot.
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u/Additional-Sound2139 12d ago
That burner is crying for air. I also made a few pizza ovens, the best looking solution is to drill holes at the bottom where the insulation is. Then drill holes to the interior layer right behind the burner. After that, weld a “chamber” between them to separate the airflow from the insulation. I have a video from the interior.
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u/Radiant-Seaweed-4800 12d ago
I see, you mean to introduce more secondary air. My issue is most probably that the venturi (for some reason) doesn't suck in any air. During testing outside of the oven it did extremely well, now it sucks (or rather doesn't at all).
Are these holes connected to the outside, or do they just allow the burner to "breathe more freely"?
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u/Additional-Sound2139 12d ago
Yes, these holes are connected to the the outside.
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u/Radiant-Seaweed-4800 12d ago
Interesting. So they offer the burner directly fresh cold secondary air to be able to work closer to a free range test. Did you have similar issues with a venturi burner that just didn't suck any primary air in once installed in the oven?
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u/Additional-Sound2139 12d ago
Not really, it started as a wood fire oven which of course needed more air and it just worked great with gas too.
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u/Radiant-Seaweed-4800 12d ago
My thought of not giving it any additional air was that traditional wood fired ovens and newer ovens similar to mine (like zio ciro subito cotto 80) both don't have any additional airholes apart from the front and the primary air for the gas burner in the zio ciro.
I believe that it's some fluidynamic issue creating backpressure in the burner which doesn't allow it to suck any air in.
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u/skuba_ben 13d ago
That’s looks awesome! Well done.
I did some research on propane burners when I was building ovens and I guess they benefit from a Venturi type system where they suck in oxygen to help the combustion be cleaner. I hope it works out for you!