Portable rocket oven

I needed to make a portable rocket oven.

Here's the result.

I cranked it to over 250 degrees C once, as displayed on the thermometer. Way too hot! I reckon the thermometer displays the temp at the front of the oven, with the back area getting much hotter.

The outer drum is insulated with 50mm ceramic fibre blanket, which is why the wooden stand doesn't burn.

Note that the unit can serve as an oven/heater combo, with a few mods, like removing fibre-blanket, making a metal stand, and painting with higher temp 'fire paint'.

Where does the oven exhaust at?

T Blankinship wrote:Where does the oven exhaust at?

Ah, yes, the exhaust. Your question links to my question here: rocket barrel oven - position of exhaust?. I explain the reason for the question there.

For this portable unit, I had to go with a single elbow from the exhaust hole exit into the flue pipe. Here's a pic of the exit hole:



As opposed to the double elbow from underneath the barrel in my immobile rocket oven:



I prefer the performance of the double-elbow shaped exit, perhaps for the reason I speculated about at rocket barrel oven - position of exhaust?

I wonder if a baffle inside the opening, with an inch to two inches of clearance all around, might force the exhaust to "wrap around" and cover all parts of the inside before exiting. I would give more clearance at the bottom with only a little bit at the top, to encourage flow from the base of the internal space.

Wow this is super cool.  I am currently looking at building a rocket oven myself, and based on what little i know i thought i had to build a riser out of firebrick.  But looking at your design, this does not seem to be the case.  What materials is both the riser and the base of the riser made out of? is the riser just rock wool insulation wrapped up in some metal tubing?

That's the famous five-minute riser. More detailed explaining in several threads, e.g.

this one

and

this one

thank you for the information about the riser, may I also ask about what materials you used for building the burn tunnel?

Hi Jenkin;
From the photo, it appears to be a ceramic fiberboard core encased by a metal skin.
You can see similar J tubes at Matt Walker's site.  https://walkerstoves.com/designs-and-plans.html
In the feed tube area firebricks are much more durable.