Replace barrel with firebrick?

[treerxjon]

Hello! I am new to the rocket stove heater idea, so I just hoped that I could get a question answered, hopefully without sounding like a complete idiot.
I am very interested in building a mass heater system, and the rocket looks like a greatly efficient design. But, I don't like the idea of using a barrel. I had seen another design where cob was used to cover the barrel quite nicely but it seems as though eventually the barrel will fail, and the whole riser will need replaced.
I was hoping that someone may have tried to replace the barrel with a firebrick structure similar to the interior insulated stack? I would hope to place a 1/2" steel sheet on the top of the riser to be able to use as a stove still, but understand that I will have to take a lot of care due to the heat expansion differences between masonry and steel.
If anyone has messed with a replacement for the barrel, I would sure like to hear what you experienced, or what recommendations you could afford me. Thanks for your time, have a good one.

[hpmer]

Here's one example of a guy who's done what you are proposing, minus the the steel top sheet:

www.youtube.com/watch?v=-jzKKIHhTU0

[treerxjon]

Very nice. Something to consider. Thank you, I really appreciate it. I am assuming that the stack/pyramid of bricks on top is for heat retention. It's a good idea. Combines the rocket stove with a Kachelofen. Much appreciated.

[Donkey]

If you're concerned with barrel burnout, then I have some old friends that have been running for 10+ years without a replacement.

Having said that, I didn't use a barrel in my stove either.. See it at the "stove at home" thread..

[treerxjon]

Thanks Donkey, I am on my way to check it out. Have a good one, and thanks again.

[treerxjon]

Ahhh Yeah! I saw that one while messing around on here. It looks great, and sounds very effective. I assume that you have some metal vs cob vs brick issues? From some of my research on masonry stoves, it sounds as though mixing different products together like that can create some trouble. I am also curious about how the cob responds as it continues to dry through time. Is cracking an issue, especially when some areas of cob are being dried (and heated) more quickly than others? I love the stove, it looks great. It sounds as though you stumbled upon a lot of great new ideas and I was glad to get to hear about them.

[Donkey]

Yep, I do.. I should have been more careful with expansion joints. There's cracking at the top where 3 different materials come together.

It's all about the mix, mate! Gotta test, test, test.. If your mixes crack add more sand/fiber, if they crumble use less. Once you get the mix figured out, most cracking problems just go away.

[sebgreen]

Hi, Take a look at this

blog.tricofolk.info/2010/12/13/rocket-stove-et-chauffage-ecologique/

it's in french but look at the final result. I'ts a lot nicer looking than most. I dont know however what they put in the mass