This is a separate question, so I thought I would create another post.
I am interested in sending some 'Flat Packed' Rocket Stoves to some buddies currently serving in Afghanistan. Ideally something made out of a flat piece of sheet metal that can be quickly assembled with included sheet metal screws or rivets and insulated with localash. While the flat pack concept has some mass-disaster response possibilities, I was just planning to ship a few so my Army Civil Affairs* associates could show the locals the design concept and once proven and accepted they could be replicated locally.
If anyone has any designs please let know. If anyone can make one (of a few), I will pay for the materials and shipping and follow up with their implementation in Afghanistan.
MAJ Patrick Freeburger 445 Civil Affairs Battalion USAR
* The Army Civil Affairs branch is tasked with working with the local population to establish local governments, local infrastructure, and provide humanitarian assistance. Because we are armed and trained to defend ourselves we can go places where most NGOs and private organizations cannot.
I am focusing my unit on appropriate technologies and attached are some pictures of a coffee can stove I built as a demonstration for my soldiers with designs on the web. FYI - The second coffee can is too small for proper insulation and will be replaced by a bigger can - A small can of water boiled in a few minutes, but the black soot implied it was not getting a good secondary burn.
I could see you mailing (flat) instructions, wire, bendable sheet metal and templates for constructing the bricks. Those receiving would then form the molds from your flat templates much like taking a flat cardboard box and folding/taping it into a 3-D object. They would then make the six bricks required for one stove. The templates could be designed to accommodate the opening so sawing of the bricks could be eliminated.
With this set up many stoves could be mailed and made.
I believe this would be a simpler solution than a fully metal design. Check it out and let me know what you think...
Nesting 6 forms to ship is certainly possible, my bigger concern is the local effort of finding the right clay/charcoal mix and the kiln to fire it in. The vermiculite or other mixes would not be feasible. I will find out their kiln capabilities and what the local soil type is.
PS Sorry for the over-sized photos in the original post - I don't think I can edit them now.
Shouldn't be a problem. panels with a hinge loop along the edges and the hinge pins could be either permanent or slipped through the loops, flue and fuel feed could slide into each other and then pack the body with clay or ash. Folding would be ideal with hinge pins permanently attached so you wouldn't loose anything. Similar to construction of a "Pyromid" stove made in Redmond, Oregon.
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Yes, sorry about leaving out the firing of the bricks (forgive me)...but I've read where bricks for indoor use can be just sun dried in arid climates. So this might be something you could test out. And armed with the great info Joel provided some kind of simple brick rocket stove should meet your requirements.
The first known bricks have been dated to about 7,500 BC and were made from sun dried mud in the Upper Tigris area of south eastern Turkey. Archeological evidence shows the first fired bricks were probably produced in the third millennium BC in the middle east. Mud bricks don't stand up to tough weather conditions, so the development of fired bricks meant permanent buildings could be constructed in areas with high rainfall or extreme weather. Bricks have the added advantage of being good insulators and storing heat during the day and releasing it slowly when the sun goes down.
Appropriate design for local needs depends on local conditions.
I haven't been to Afghanistan. If you want to get back to me about local conditions, I'd be happy to help tailor a set of instructions that your guys can work with.
From my 'armchair,' I get the impression that Afghanistan is arid and mountainous, with limited areas fertile enough for commercial agriculture.
Arid, hilly regions in the US west often have excellent subsoils for making adobe or cob, but fuel is scarce.
Firing bricks uses a ton of fuel. Might be a problem if you're trying to help the locals with low-fuel stoves. If it's economical to fire bricks there, locals will have a method and access to bricks. If not, it may be more trouble than it's worth. Insulative bricks can be created without firing, either by using cement or by building in place with minimal transport.
Local ash can certainly be a good insulator. Sawdust and clay make an insulative foam (the sawdust burns out, leaving holes). Local agricultural wastes like wheat chaff could be used in the same way, mixed thoroughly with local clay slip.
I'd also look to local waste products for forms and liners - like your coffee can example. If a special tin kit gets shipped over, it will be hard to replicate locally. There are probably some ubiquitous scrap materials that will still be plentiful after the Army leaves, and these would be a good source for liners.
Some of the SE Asian fruit drinks, for example, come in very sturdy steel cans for extended shipping. If those are also common in Afghanistan, try them as a cylindrical liner for a tiny portable stove chimney, with a larger can around the outside. Rectangular steel cans from kerosene or cooking oil can also be handy, if they are locally disposable rather than reused.
One risk I see with this approach is that it could seem 'junky.' Earthen bricks might fit in better, and be easier to maintain locally once the liaisons are gone.
You may not get a completely clean burn with any of these small stoves. Approvecho http://www.aprovecho.org/lab/index.php has been developing variations on insulated metal stoves for years. (They sell kits / instructions too.) They are aiming for clean air, but they all put out some amount of soot. A chimney on the stove, or a hearth vent, can help reduce indoor smoke in cold regions.
There's also a thread on these forums for a "fox stove" that you dig into the ground for camp cooking. Can be useful for folks on the move.
Your guys on the ground may find the locals are pretty sophisticated about fire; more so than most Americans, who have the utilities to fall back on. As long as they're willing to learn as well as teach, it could be a great cultural outreach project.
Ernie points out that sheet metal in a war zone can be salvaged from munitions as well as canned goods. In Pakistan, this historically included children going out to collect both spent and unexploded shells for their brass casings. This is likely to happen regardless of stove design, but it might be a consideration in promoting brick vs. metal.
So: questions about local conditions: 1) What foods are they cooking, and how? Fried, baked, boiled, steamed? 2) What do the current local stoves look like? Are they indoors or outdoors? 3) What fuels are commonly used? 4) What materials do they have on hand? Junkpile, barnyard, dump, rag-pickers? 5) What secondary use do they expect from a cookstove? eg home heating, portable, trash disposal, aesthetics, etc.
Cultural Considerations: 6) Do they share communal kitchens/bakeries, or is cooking done in each small household? 7) Does the liaison team have the ability to work directly with Afghani women/cooks? Helps if there are women and/or cooks on the team. Teams working in Africa who talked to the men (not the cooks) were led astray by uninformed opinion and enthusiasm, and the resulting stoves were pushed on the women but not widely accepted or replicated. Who builds the stoves? Cooks, family members, the community, or specialists?
These are the questions we'd be asking if we were on the ground. Knowing the answers can make or break the appropriateness of a new cooking technology.
Hope this helps.
If you've already considered these things and just want kits, please get in touch. We can help create instructions and other flat-packable supplements to the materials on the ground.
Best of luck with the project. Please let us know how it goes!