• Post Reply Bookmark Topic Watch Topic
  • New Topic
permaculture forums growies critters building homesteading energy monies kitchen purity ungarbage community wilderness fiber arts art permaculture artisans regional education skip experiences global resources cider press projects digital market permies.com pie forums private forums all forums
this forum made possible by our volunteer staff, including ...
master stewards:
  • Carla Burke
  • Nancy Reading
  • John F Dean
  • r ranson
  • Jay Angler
  • paul wheaton
stewards:
  • Pearl Sutton
  • Leigh Tate
  • Devaka Cooray
master gardeners:
  • Christopher Weeks
  • Timothy Norton
gardeners:
  • thomas rubino
  • Matt McSpadden
  • Jeremy VanGelder

no metal rmh?

 
Posts: 73
Location: Essex, UK
3
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Metal barrels are as rare as hens' teeth around here and flue pipe is prohibitively expensive too, so I pretty much need to avoid metal but I would really like to make an rmh.

I know a rocket stove is doable without metal, but a lot of heat is wasted, which I would like to 'capture' in a cob bench/sleeping platform. I am concerned that without the rapid loss of heat provided by a large exposed metal surface, there will not be sufficient force in the draught to force the exhaust through any significant lenght of horizontal flue, especially once the downward section has warmed up.

The only examples I have been able to find of anything without metal are just stoves, and only one of them a proper rocket even. The best of them is Glenn Herbert's, and that exhausts into a vertical flue, after only a tiny downward section.

Being unable to find anything like what I am hoping will work, makes me very wary of the massive amount of work involved in making a cob bench in the first place. . .

If anyone has made one, or has seen one that works or has a link to one, I would love to hear about it.
 
out to pasture
Posts: 12519
Location: Portugal
3399
goat dog duck forest garden books wofati bee solar rocket stoves greening the desert
  • Likes 1
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Have you seen Matt Walker's Tiny House Cook Stove Heater?



You'd still need a bit of metal for the door, but there's none in the stove itself, and the bench is different type too, with no flue pipe.
 
rocket scientist
Posts: 6401
Location: latitude 47 N.W. montana zone 6A
3247
cat pig rocket stoves
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Hi Marion; Your flue/mass is easy,   Brick tunnel of the proper size is easily built, or brick bells also work very well.    As far as a barrel.   Steel pipe  can be used but it must have a top welded on. Used culvert would work.  Even sheet metal (if you can weld it) would work.  
Have you checked at any mechanic shops for a fluid barrel?   School bus maintenance shops , even farmers end up with a barrel or two around.  
As a last resort I would use all brick , it could heat up and stall but, that would be more likely  with a flue pipe rather than if you use a brick bell arrangement.
Keep looking about and talk to people about what your trying to build. There may be just what you need sitting unused in somebody's barn waiting for you.
 
Marion Kaye
Posts: 73
Location: Essex, UK
3
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator

Burra Maluca wrote:Have you seen Matt Walker's Tiny House Cook Stove Heater?

You'd still need a bit of metal for the door, but there's none in the stove itself, and the bench is different type too, with no flue pipe.



Thanks for posting, but actually yes. It's not just having a door that put me off it though. Among other things more personal to me, I don't see how he can call it a rocket stove when it doesn't have a riser, and in the video he actually titles it a masonry heater . . .

Looking on the positive side though, it does seem to be exhausting satisfactorily through a bench even without a riser!!

Posting on here seems to do wonders for my search results, at least, for a little while. . . I've actually found a couple of diagrams and pictures of almost exactly what I am thinking of making, and afaict they work alright!


Hi Thomas, to cut a long story short, between my finances and ministry of sadness wranglings, for metal, I am limited to what I have had lying around for years, and that's not much!
I do keep my eyes and ears open for anyone who might be interested in these sort of things, but due to the normal (i.e. not like me ;P ) demographic of the area I live in, the closest I have found was over an hour away, and they had to remove it or be unable to insure a very expensive (and wooden) building . . .

Filename: stovermh.bmp
Description: very rough drawing
File size: 2 megabytes
 
Marion Kaye
Posts: 73
Location: Essex, UK
3
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Hmm looks like I need to host on photobucket or somewhere first
 
gardener
Posts: 3471
Location: Southern alps, on the French side of the french /italian border 5000ft elevation
194
  • Likes 1
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Marion



http://batchrocket.eu/en/applications#culdesac

Just showing two options.  With a bit of research, you can find tons more.  


If barrels are rare as hen's teeth where you are, either you are not in essex, or you're not searching well.

Try earth moving businesses, auto mechanics, coach companies etc. Wherever there is mechanics who need oil, grease, coolant etc.

Otherwise, old home heating fuel tanks, for example, can be used. Old agricultural tanks, cast iron bathtubs for the bench. Plenty of options.

http://donkey32.proboards.com/thread/1817/starting-build-220mm-rocket-double

http://s65.photobucket.com/user/mremine/library/NYC%20Rocket%20Stove%20Build?sort=3&page=1


https://www.google.fr/search?q=rocket+brick+bench&source=lnms&tbm=isch&sa=X&ved=0ahUKEwifpqHg8I_cAhVHPhQKHRRVCNcQ_AUICigB&biw=1228&bih=599#imgrc=HR2vWlg55fgOhM:

 
Rocket Scientist
Posts: 4543
Location: Upstate NY, zone 5
582
5
  • Likes 1
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
I did use some metal in my RMH, but it could be avoided easily. I have a masonry and cob bell, which could be done in all cob (but with less safety and code compliance).
Rocket mass heater with 8" J-tube and bell

My steel feed insert could be replaced with a firebrick feed easier and cheaper... I wanted to try it for the p-channel supply and air preheating; it works very well, but is not essential to operation.
An access panel to inspect the riser is a really good thing, but could be done much more simply than mine if you are not concerned with "living room" esthetics.
 
Marion Kaye
Posts: 73
Location: Essex, UK
3
  • Mark post as helpful
  • send pies
    Number of slices to send:
    Optional 'thank-you' note:
  • Quote
  • Report post to moderator
Oh awesome!!
Thank you so much for the link, I'll post more on there, when I've studied it more closely. This thread had gotten very tedious, but now it's turned up gold, I'm glad I asked.
 
Time is the best teacher, but unfortunately, it kills all of its students - Robin Williams. tiny ad:
The Intentional Community Summit - Feb 21-23 (2025) - online
https://permies.com/t/273995/Intentional-Community-Summit-Feb-online
reply
    Bookmark Topic Watch Topic
  • New Topic