I'm in the process of designing a rocket pizza oven that /i will start building in the up coming months.
I've just got a few questions I wouldn't mind some expert opinions on.
Firstly Whether to do a J tube or L tube. I know most people are building J tubes but I've heard that it is easier to control temperature with the L tube.
Considering it is for cooking I thought this might be ideal.
The second question is where to bring the heat riser into the oven.
There aren't too many videos but I have seen two main designs.
- Bringing the heat riser up in the very rear or the oven and venting the chimney out the front near the door, the cooking surface would be on the brick oven floor. This would bring the hot air up over the cooking food (pizza and pies mostly)
- The second option I have seen is bringing the heat riser up through the center of the floor, suspending a cooking surface like a pizza stone and then venting the chimney out of the top/center of the dome for even air flow around the food.
can't help you on this, but we (well, some people I'm working with) are considering building 1 old style wood fired bread oven, but also 3 mobile (on a trailer or something) ovens for pizza and other oven dishes.
At the moment, they are looking for the older type of pizza oven, but with a good rocket system, that would reduce fuel cost off course.
In other words: I hope someone comes up with a good idea/design/I don't care as long as works thing.
Glenn that is an amazing rocket oven.
I'm inspired to try make a dragon like yours but I suspect I wouldn't quite have the cob skills to do it justice.
I think I will go J-tube and bring the heat riser into the center of the oven under a baffle plate.
Still haven't decided where to bring out the exhaust. What different characteristics do you get out of bringing out the highest point of the dome vs lower down toward the door?
Presumably with the latter you get a hotter/more effecient oven as the hottest air gets trapped at the top and you vent out cooler air but I wonder whether you get uneven cooking as the majority of air travels from the heat riser toward the exhaust.
With the heat riser outlets toward the sides & back of the oven, putting the chimney near the door will bring the hot air across most of the space. I think that will give the best results. You might even have the riser on one side and the chimney low on the other side, for even better heat trapping.
Well, first of all, you have to understand that a baking oven and a pizza oven are not the same thing.
Pizza need a violent fire and a very hot slab (do you say sole?) , to get seized by the heat. And work with the door open.
A baking oven relies on heat accumulation.
They're in turn, not that far away either.
A pizza oven with a thick arch can work well too.
My take, use a batch to power it. Less fussing around. And you don't need to control the temperature of the oven, beyond inside accumulated temp.
With a batch, you will have the power for a pizza oven.
For the heat riser exit, i hesitate between two solutions, either on the right side under the arch. Or on the right side, under the slab with a gap. I haven't tried either. Always used a conventional pizza oven. (3 years in a french restaurant) For the chimney, i would do two. One on the very left side, a wide slit, about 1.5" from the slab. or, if for ease of building you want simpler, a plunger tube.
And a traditional pizza oven chimney; on top of the of the oven door arch, on the outside. Basically, you close or open the door, leading to the chimney, to regulate the draft while preheating. Taking the door completely away when you make pizzas. The smoke, (in a normal pizza oven), goes directly in the over arch chimney, and so you can get close to the entrance of the oven without killing yourself with smoke.
The idea behind the plunger tube being that the oven, when the door is completely closed; acts as a bell, accumulating the heat as much as it can. Then if you work door open, to make pizzas, you still have the door top chimney, which would prevent the occasional gust of smoke reaching your lungs. It would also be a good idea to make a damper in the plunge tube, to keep the most heat in, when the fire if down.
Paul's new video clip about the Rocket Oven movie can be seen below. He chats about various things including design considerations for the j-tube and wood feed, with suggestions on how to adapt the oven for permanent installation. Might be helpful!