Brian Van Dine

I first became aware of rocket stoves for cooking before I became aware of rocket mass heaters. I have found a good resource for learning about the technical aspects of rocket stove design. There is a facility that is devoted to exploring sustainable technologies and rocket stoves for cooking are a primary focus. The resource is www.aprovecho.org. On the home page of this website you can download a PDF book of over 100 pages that details laboratory experiments they've run with different rocket stoves - they actually have built a lab with testing equipment! The PDF examines that various factors of rocket stove effectiveness and what they've discovered are key issues. They also produce videos and at least one video I found on Youtube by this group details how they make their rocket stove for cooking. They actually make their own fire brick, which implies they must have a ceramics kiln on site as well.

It would be nice to know how to construct a wood fired kiln in order to make one's own fire brick. Interestingly, I did do a little web surfing to try to find small wood fire kiln designs. I found some forums that primarily consisted of professional or amateur potters, understandably so, but there were also a couple of posts from folks who had homesteads and who made their own earthen vessels on site. Also, it seemed like most of the commenters weren't aware of rocket stoves, but one post did raise the question of whether rocket stove technology might work for kiln design. There appears to be a potential opportunity for some cross-over discussions which might eventually yield a design for a hybrid between rocket stove and kiln. Who knows?

Just an idea. Any of the racks pictured in previous posts would seem to work, but if you didn't want to hang it directly over the sink, but would rather hang it over another counter area, you could simply take some thin sheet aluminum to make a custom-fit shallow tray that is attached to the bottom of the rack. The edges of the tray could be bent up wards and the corners - with tabs - folded over and pop riveted. The bottom of the tray could be flexed from diagonal corner to diagonal corner (before folding the edges) to make a slight "X" bend in the flat of the tray. This would cause the intersection of the bends at the center of the "X" to be the lowest spot so, water would collect there. Drill a drip hole at that point. If you need a small spout to protrude beneath the drip hole to guide the drips you can use a short piece of small diameter brass tubing - the best being a spent .38 cal. brass casing as it has a flange at one end to keep it from falling through the drip hole. If you can find a spent .38 cal. casing you would drill out the primer base to enlarge the hole to facilitate drips. If you can't obtain a casing, you might just solder a washer to a piece of brass tubing to make a flange, instead.

When using the rack for drying, place a cup beneath the drip hole to collect the water. Use the collected water to hydrate a house plant.

Kyrt Ryder wrote:

Brian Van Dine wrote:Although, I've always been interested in finding ways to work with nature instead of against it.....Contemporary building practices work

These two statements seem rather contradictory to me. Do you mean you want to see alternative technologies that are compatible with contemporary buildings as part of a transitional phase while we get out of these horribly inefficient, non-sustainable and oppressive-to-owner-builders contemporary building practices?

The short answer is, "Yes." Personally, I don't view what I said as contradictory. Some activities work very well with natural principles in the short-term, they are expedient solutions to immediate problems, but eventually reach long term limitations. The global warming phenomenon is just such a thing. The internal combustion engine, as I mentioned in my first post did enable society to create industries and institutions that overall support more total human beings. However, we are starting to see what the limitations to these technologies are and of the institutions that rely on them.

I used to make wine and beer. I found it interesting how the yeast would multiply rapidly in the beginning when there was ample sugar available to consume. However, over time the yeast drown themselves in their own waste output - alcohol and CO2. Global warming is sort of like the yeast.

The way society does things (the inefficient, non-sustainable and oppressive-to-owner-builders contemporary building practices) didn't just happen overnight. They evolved over time in increments. Each increment represents a short-term solution that seemed to work at the time. Institutions evolved from this process. Institutions interact with one another and form a social ecology such that the activities of each institution reinforce the others. The outputs of one institution are consumed by the next and so on. Gypsum producers sell product to drywall manufacturers who sell to building supply outlets who sell to contractors who employ dry wall installers who are ultimately paid by the house buyer. That's just one chain of ecological interactions and it's not easy to interrupt.

So, changes have to be made gradually. Transitions need to happen where more sustainable technologies are introduced along side conventional ones. New institutions have to evolve around those new technologies such that the end result is more sustainable. To accomplish that will take longer-range thinking than what the yeast were capable of, or even perhaps, what people are capable of. Any way. That's how I see it.

Although, I've always been interested in finding ways to work with nature instead of against it (it just seems more efficient) I'm relatively new to the study of Permaculture. For this reason, recently when I saw a “Sustainability Fair” being put on by a local community college, I went to check it out.

I was dismayed, however, to see that very few vendors were actually offering real permaculture information or technologies. There were several groups organizing a protest march against BP Oil, some selling buttons and bumper stickers about how we should get along and make love not war, etc., there was a vendor selling crystals for healing, a chiropractor promoting natural health, and even an organic hair salon – what ever that is? There were a number of vendors handing out pamphlets about adopting more “green” behaviors and they were vocal about saying, “We have to do something!.” Yet, when I questioned them in depth about what steps we should take they were less clear about their visions.

My first comment is that for permaculture to be taken seriously by the masses it will have to gain adherents in the sciences, economics, and politics (Al Gore doesn't count). Folks promoting protests and folks selling crystals that are supposed to have healing powers don't, in my opinion make for the best spokespersons for a positive impression that Permaculture is something to be taken seriously by the scientific community.

My second comment is that although I am fascinated by rocket stoves, bio-digestors for methane production, composting, and other natural technologies, I'm very turned off when the result of these pursuits leads to a dwelling that is more suitable to Frodo of Lord of the Rings than for contemporary suburban America. Contemporary building practices work for most Americans. Not only are they practical to live in but they keep a lot of folks employed building and maintaining them and the building codes are institutionalized.

My third comment is more an observation. In the 1800s, the industrial age produced a situation where it was more profitable for the average person to migrate to the city for a factory job, leaving fewer farmers who were mechanizing (due to the tractor and internal combustion engine) to produce the food. This eventually led to large corporations, including corporate farms and agricultural product producers. Without these corporate farms, millions of people in the cities would starve to death.

Fourth, individuals, small businesses or large multinational corporations, like all living things, have a strong urge to survive. Unless I'm mistaken, the field of permaculture is intimately related to the study of ecology. In the 1960s, the Social Sciences adopted the ecological perspective from biology and derived “Social Systems Theory” from it. This theory views human organizations as like organisms functioning within an ecological environment, something which I should think might come rather naturally to those studying permaculture.

My third and fourth points are to stress that when viewing the problem of large corporations, how they operate, and the damage they do to sustainability, we must view these institutions in light of ecology. If a pest issue arose with your permaculture food crops, how might you address it? The modern way would be to use potent poisons to eradicate the invaders as quickly as possible without regard for the side effects. I expect though, the person who embraces permaculture might try a more sophisticated, natural approach by studying the various ecological cycles involved, brainstorming how to divert the pests to a new target or how to erect some natural obstacle to the invaders. The goal being to change the homeostasis of the entire ecological system so that the food crops would be spared.

Permaculture contains the word “culture” in it. Culture is derived from “Cult,” or what people believe collectively. You can't promote permaculture to the masses and get them to buy into it if it doesn't address their perceived needs. If permaculture as a field of study can be embraced by the scientific community, the economy, and politicians it will gain wider acceptance. If the technologies used in permaculture can be made to work in greater harmony with contemporary building techniques and architecture, this too, will cause more people to take the plunge toward permaculture. Corporations, industries, institutions and individuals all have a strong instinct to survive and they do this by ingesting income. People will flock to permaculture if it can be made commercially successful.

If these things cannot be done, permaculture will remain the realm of a relatively few individuals who live rurally and fairly isolated at the fringes of society and that would be a shame, I think.

Thank you for this great info! It sounds like my initial build is salvageable at least and now I am more aware of key concepts for my next build attempt.

Thanks for the advice.

To answer your questions

The insert the sticks lay on is as long as the horizontal pipe - 18"

I'll get to work on reshaping the insert as you suggest. I'm a little surprised as I thought more air was the critical factor and that I was somehow going to have to figure a way to get more air into the chamber. But, reshaping the insert is an easy fix.

You asked about the space in the back for fuel/air mixing. The horizontal pipe only protrudes into the riser about 1", so I'd say, given the riser is a 6" stove pipe that there is about 5" beyond the horizontal pipe. Is that too much space, perhaps?

You mention the ash pit isn't useful. I'm not picturing the modification you are suggesting involving something about the horizontal pipe an inch long and a "tee." Are you saying that the intake pipe is way too long and should only be about an inch long? The horizontal intake pipe is already inserted through a hole in the side of the larger riser pipe - is that what you mean by a tee? I can shorten the horizontal intake pipe to what ever length is recommended. Trying to place additional fittings on the back end, however, would be tricky as there isn't a lot of room to work inside the 6" riser into which the horizontal pipe is inserted

I have considered the benefits of lining the metal with clay or something but I'm not sure what material to use? When you suggest a clay mix is it the ceramics clay like potters use or something different? Where does one purchase said material? Thanks.

Greetings!

I'm new to the forums, but having been reading through them I'm impressed with the expertise available. A couple of years ago I made a coffee can rocket stove that seemed to work well enough to heat a pot of soup to boiling. Having read how they burn wood more efficiently at higher heat, I thought, "That's what I need for Asian stir fries in the WOK." So, I set out to make a larger version to use on my deck utilizing what I thought were most of the same principles that seemed to work in the coffee can rocket stove.

CONSTRUCTION:
I've attached a few photos to help communicate the design. I used a galvanized steel garbage can for the shell. The riser pipe is 6" stove pipe, the bottom of which is capped off with the fitting for that purpose. The horizontal intake pipe (which actually inclines towards the center of the stove ever-so-slightly) is of steel. I don't know what kind of pipe it is but it came with an aluminum liner inside which I have removed in order to get more inner diameter. I fashioned a tray for holding the sticks in the upper chamber of the intake pipe from steel sheet metal which simply slides into the intake pipe.

I cut a hole in the stove pipe (riser) into which the horizontal intake pipe could be fit. The bottom - capped portion of the stove pipe riser is about 2/1/2 - 3" below the lower lip of the intake pipe. which creates an "ash catch basin."

I was concerned about the device tipping over either because of wind gusts or becoming top heavy with a WOK full of hot/sour soup sitting on it. Therefore, I sought to add some ballast which I accomplished by mixing some hypertufa (1:1 cement and pete-moss). I figured that since hypertufa is lighter than straight cement it is due to the pete-moss filler and so the hypertufa might have a better insulating effect than straight cement. I was trying to avoid a big heat sink. The base of the garbage can is filled with hypertufa which is about two inches thick. It comes up to just under where the horizontal intake pipe comes into the riser. I did use a small amount of the hypertufa to seal any gaps where the two pipes came together.

The remainder of the garbage can is completely filled with a mica-insulation (billed as vermiculite) and it must be effective because the outside of the garbage can doesn't even get warm no matter how much fire is in the hole.

At the exit of the riser I measured, cut, and bent two inch wide tabs every other one either bending inward or outward, the result being two concentric circles consisting of five tabs each which serve as grates on which to rest pots, pans, or WOK of different sizes.

PERFORMANCE:
I consider this device to be a failure overall, but providing good opportunities to learn. To ignite the stove I wrapped several smaller sticks about the diameter of my fingers, each in several sheets of news paper and shoved them down the barrel of the riser. The fire quickly builds into an audible roaring fire as air is pulled into the intake pipe and jet-like flames shoot out the top. However, as the fuel in the vertical riser is consumed and used up, the sticks protruding in horizontally from the intake tube are insufficient to keep the fire going. I end up with glowing embers. On a particularly windy day, facing the intake pipe into the prevailing wind, a few prolonged gusts did reignite the glowing sticks into flames, but they quickly went back to glowing embers when the wind died down.

What I seem to have is a good incinerator. A lot of fuel in the vertical riser can cause enough draft to get it going. However, the main fuel sticks are insufficient to maintain any drafting, therefore, I don't consider this to be a workable rocket stove. As an added note, the hypertufa does heat up and maintains significant warmth hours after the fire goes out as the bottom of the garbage can is quite warm to the touch.

I would appreciate any insights the experts can offer about what I might have done right and where I went wrong. Thanks.