Rocket MH: bricks, stones, and without any iron...

Hi guys!
I will comment regularly and add photos...
Today was the start: removing earth from the chosen place.

I wanted to make this RMH without any steel pipe, just with masonry.
Then came the idea to suppress the barrel as well!
(I still have not found any, even for sale)

Has any RMH been built like this?
Any link to pics, videos...?

search the boards for masonry heater, there have been some great links posted in the last few days...just make sure you're using the right kind of refractory in the right spot

I am not building a masonry heater but a rocket stove without using any pipe nor oil drum.
I guess there is a difference, I really mean I will use the rocket system (I have Ianto's book)

Thanks Andor, I am searching some links and exploring more...

...I guess I'm not sure what you're shooting for; mass heater only?

"Rocket" anything means (to me): highly insulated combustion unit operating at high enough temps to acheive complete fuel combustion. Only after this unit (component) is heat extracted...

here's a link to a small combo unit: http://www.firespeaking.com/portfolio/the-cabin-stove/ (not really a rocket, but might be on the path you want to go)

otherwise you might want to find the "bell" discussion over at Donkey's board if you want to go all masonry and heat only.

hope this helps

That's not like this cabin-stove.
This is not after the principals of the masonry heater.
The technologies are not the same so I do not understand the mix!

I go for a rocket mass heater.
But no metal part.

It will be a rocket with its J shape and the internal chimney,
with gases going down after hitting a "roof", but that "roof" will not be a metal barrel.
I want to do it all with stone.
I can also buy refractory bricks if they are absolutely necessary.
So the feed, the burning chamber and the internal chimney will be with stone and or bricks.
I know this has been done.

That is masonry instead of metal pipes, but still a rocket stove.

Then, how to replace the barrel...
This I want to know if it has been done before.

I just want to go it with stones as well. I even have no problem for the top.
And I have large, light, very insulated stones.
These were traditionally used here for putting inside bred ovens.

Of course I will not cook on it.
You need the hot metal top for cooking.

Xisca,
The barrel is metal for a reason. The radiant heat loss that the gasses undergo (by transfering heat to the air of the room) lowers the temprature and drives the downward "push" that alows the rocket to fuction. If you use a material that insulates or has thermal mass you will kill the rocket. That is also why your heat riser needs to be very insulative (no thermal mass): To keep the temperature differential between the upward and downward moving gasses.

Masonary fuel loading area, Kiln-brick burn chamber, Kiln-brick riser, metal barrel heat exchanger, from there onward you want thermal mass and then an exit chimney.
If you look at the material properties of the above, you will understand why it is a recipe for sucses.

Of course, experiment with anything you want, but just keep the physics of what you are trying to achieve in mind, and choose materials with logic.

I do understand the necessity of insulating the inside and especially the heat riser.
I have already seen that this heat riser could be made of refractory bricks instead of a double pipe with vermiculite.

I had never read that the heat loss thanks to the barrel was a necessity!

I finally found that rockets have been made without the barrel:

http://www.handprintpress.com/home-heat/recent-research-on-rocket-mass-heaters-and-bell-design/
http://www.mha-net.org/docs/v8n2/wildac09f.htm

Then, how can this work fine as it looks??

try this: all masonry; http://www.flickr.com/photos/rocket_stove/show/
and here's the bell discussion on the other board, it's long, read it all
http://donkey32.proboards.com/index.cgi?board=experiment&action=display&thread=113

Ok thanks Andor, I have checked this....
The flickr link is not only masonry, there is a steel pipe in it. And there are only photos, so not easy to guess how it was made inside.

I had read the bell discussion yesterday, and this is more complicated to do than a rocket.
The experiment is great, but after all what Peter tried, we do not know what really works and how to do it, nor the size of each part of the system.

I am really going to stay on a basic rocket design!
I also cannot go upward that much.
What is special in my design is that I will be caving directly in this soft stone... in the cliff.
I want to cave the hole, then build the J or L shape in the hole (that hole will represent the backward part of the usual barrel), then close the front with stone or bricks.
So the hot gases will reach the stone instead of the flat surface of an oil drum. Then the gases will go down on the sides normally. There will be the normal ash-tray and then a mass. I even plan 2 masses: a bench outside and a bed inside.

My concern is more about: "Can we really not do without a barrel or any kind of stuff in steel"?
(I refer to Chris post)