Well, a new heating season is begun and with it a new iteration of the previous Rocket stove, called a Double Shoebox Rocket.
The group over at the Donkey forum did some experimentation back in 2018 coming up with this concept, which was later abandoned by Peter van den Berg, the chief experimenter on the project, as being too unreliable.
By the time he had moved on to a different design I had already started building, it was getting colder, and looking at the elements that seemed to make the DSR run away with the burn, they did not seem as relevant to my design, so I just continued to build according to his best guess dimensions.
My 2018 build used a number of walls that were simply formed of clay, or a clay perlite mix, and a couple of the sides around the water tank were taken from an old washing machine, with some fiberglass insulation hastily fastened to the inside of the walls, with clay slopped around the top and edges to give a seal.
The door to the burn chamber, as in many projects done on the cheap was a problem until I finally bought a couple pieces of neoceram stove glass, which cost more than all the previous stoves from the last several years.
While this new glass has proved very durable, having a door that really is robust requires more than just a glass pane, so that is still in the development phase, although I’m pretty sure I have a workable solution which will likely happen sometime during this season. For now I continue to get a potholder if the glass is hot, and as gently as possible remove it and then wedge it back into place.
The other main change is the use of bricks to give a substantial continuous exterior that is well sealed and even looks a little better.
One other important note, my exhaust was set up for a low temperature ground level “stack” and to use the push of the j tube rather than the pull of a draft. Since the first batch box conversion about three years I found it necessary to install a fan at the end of the exhaust pipe to aid with the draft. This totally eliminates smoke at start up and keeps the draft more even.
So it’s getting pretty cold outside, and when I built the last version of my stove I promised a breakdown analysis after I had used it for a season and had a chance to sort out my experience. Now that I have rebuilt the beast it seems the time is here to write about it.
First I would say that overall it performed pretty well, the weakest part of the thing being the door. The visions cookware lid I started with did work, but I would not plan on using such a thing except in a pinch. Eventually the first one cracked, primarily from physical shocks because it really does get too hot to handle at times leading to bumps and drops, and once hot it will use any excuse to crack.
Over the three to four month life of the stove there were numerous tweaks and while the final product worked, it would never have lasted another four months without many more overhauls.
My building style was primitive, using lots of clay and perlite, which was always sufficient in the original rocket stoves I built, but with the more compact and intricate design of the DSR bricks are really the way to go for all vertical surfaces, not just inside the firebox/batch box. Also bricks give an element of speed to the construction, and the finished product is structurally more stable. With clay walls on much of the old stove, cracks were commonplace, and I often worried about them just falling completely apart. If you do want to use clay, make sure it is a continuous mold type process. Forming one wall one day and then adding to it or building an adjoining wall the next does not give a reliable bond.
The water tank was the next area of interest, primarily because it was an issue I had to revisit many times, especially after one spectacular failure. My theory that pex could withstand temperatures in excess of water boiling was good only to a point . Hot, therefore soft, pex under extra pressure will blow out. Use all metal fittings inside the heat chamber and for a distance outside the chamber, and of course, when heating water, always have the system open so steam can escape safely. Pressure relief valves are a real good extra insurance in case one forgets to depressurize the system.
Soot was present everywhere the exhaust touched , except the parts that got the hottest in the burn chambers. The thought occurred to me that I had basically turned the entire downstream part of the stove where heat was extracted into a creosote trap, and future builds will have to accommodate an easy access for periodic cleaning.
Future builds will also need to be more efficient, and since start up and cool down phases of the burn are the most problematic, shortening those periods compared to overall burn time will be a major concern. Quality dry fuel will become a major goal for operation of the next iteration of the stove.
Recently I read more about the continued development of the DSR II and it has taken some interesting turns. I’m not sure I will be using all the developments, but at some point I will likely be adding a short riser at the back of the firebox. That will likely wait for me to get some ceramic fiber board, so for now I’m just using the old DSR design.
I was a bit remiss taking pictures as I dismantled the old DSR, and obligations elsewhere meant much of the new construction was not overly documented, but look at the next post to see how the new DSR changed.
This has been a drastic change from last year when it was too wet to do much. This year it has been very dry, and instead of water, dust, dry powdery clay is the issue.
It’s kind of interesting to watch the tendency of the mind to be so centered on the moment and when right in the middle of a situation things can seem so permanent that it’s difficult to remember there can be another condition. When it’s dry for a long time it’s hard to remember the water, and when it’s wet, it’s hard to believe things will ever dry out.
Puts me in the mind of the Arkansas Traveler, and the man with the leaky roof who doesn’t feel need to mend it when it’s dry, and when it’s wet it’s impossible to mend it. The end result is the roof continues to leak.
But here that isn’t the case, I’ve had the backhoe in several places that would be impossible in wetter conditions. I went down to the oldest goldfish pond where I couldn’t begin to go last year at this time. With a firm footing underneath the backhoe can go more places and dig out ponds deeper and wider, with less mess.
Creating deeps in a pond is important for many reasons. It gives fish a place to hide to escape predators, provides protection from cold and heat, and also reduces surface area evaporation in extreme drought, giving the fish that last refuge when everything else has dried up.
Regardless of the purpose of the action, there seems to be a strange relationship between the opposite conditions, and often the solution for one extreme is found when the pendulum swings in the other direction.
When it is too wet it’s easy to see where water has found weaknesses in the design, when it is too dry it is possible to rearrange and correct the design for the next time when water is in abundance.
Close to 100 degrees yesterday, 80 today, and barely 70 tomorrow. This feels more like August than October. Just writing it has me even more amazed at the extremes.
It’s tough to keep the few plants left alive watered and with dwindling reserves and little rain in sight everything must be rationed. The middle dam gave some water to the goldfish pond, the small garden pond donated water to the pepper plants, and the catfish in the upper pond have to do without as I watch their pond recede.
Since dry clay does not compact well, backhoe work is limited to establishing the filtration system for the middle pond, and spreading gravel on the driveways.
Dry weather is a good time to work on the driveways, so scraping the drive on the front side of the creek yielded several loads of pine needles and wood chips for the gardens from the other side of the creek, and then adding gravel helps them become more even and dependable for wet weather that will eventually come.
The one area near the middle dam was a creative event to gather more clay for the middle dam, and the sharp cliff that was left will hopefully establish a micro climate for many of the fig trees that have been living in the green house. It’s time to put together mulch and soil there so they can be replanted for their first unprotected winter, and sand and wood chips with salvaged top soil from the pond sites will be primary soil builders for them. A little compost will help as well to contribute lots of soil organisms.
They will also get a very heavy mulch of leaves once planted and with some luck become a regular fig forest.
This post has now officially become a running commentary on the last several months. With other imperatives in my life aside from these projects in Permaculture my house and gardens have suffered serious neglect, but with luck that will change in the coming week.
The dry spell has definitely broken, and I have been told my ponds are filling up. Looks like I may be waiting another year if I want to do any more digging on the upper pond. In fact, back hoe adventures may be severely limited to smaller projects and times when driving it from one location to the next don’t dig deep ruts in the ground.
Retreating inside or to hand tasks in the garden does have its advantages. Rest and planning are at the top of the list. It would be easy to get bored and start chaffing at the bit, leading to misadventures and more harm than good, so having a variety of projects, both inside and out can be a very good thing.
As the weather gets cooler, I’m reminded that the newest version of the rocket mass heater needs to be built. There’s always inside cleanup, and the roof skeleton definitely needs some more work. Not to mention finally fleshing out this post with the pictures it so desperately needs to continue a complete coverage of ongoing developments.
With that I will close, but pictures will be added soon and maybe this post will actually get published. 🙂
These are the times a good water system is vital, both for crops and natural systems. With my dams still just babies, and deliberately draining the top dam early on, the water level up there is going down fast–but not as fast as last year. likewise the middle dam is going down, but even now it is still higher than at it’s peak last year.
As the dams grow in height and excavation inside the pond winds down, I will be able to fill that upper dam and keep more water for a much longer time. the swales (once they are built) will keep the water in the soil saturating much more of the landscape.
In a few years any carbon I lost cutting young trees will be compensated by faster, better tree growth during times like this. Also of course, the garden will have ready access to gravity fed water once the pipes are buried and the siphon systems are in place.
Way back before I ever suspected a dam or high water storage, I installed an extra 3/4 inch pipe from garden to cistern. I never knew what it might do, and for a long time I thought it was wasted energy, but now that pipe will be one chain in the link of the coming irrigation system.
Also, looking at the top pond, it is very green- thanks to the catfish-algae that will make excellent fertilizer for everything. Soiled water may not be ideal for house uses, but the plants love it.
Anyway, this is the weather I’ve been waiting for, time to get the backhoe moving dirt from the back of the pond to the dam. I’ll also have to dig the sediment pond in back and establish some sort of small fish nursery/ fish food cultivation system.
I don’t anticipate much swimming in that upper pond, but a sediment system could also act as a filtration system just by adding a pump if swimming does become popular.
It has been an interesting week, going back to salvaging an older, but still quite nice entertainment center. Bringing more stuff back to my junk yard might seem counterproductive, but in finding a place and setting it up I had to clear an entire wall near the work area.
That particular wall seemed to have stuff that was difficult to move and get to, so it was difficult to even consider cleaning it up. The results however were great. That entertainment center is a nice addition, some places for storage, but more important, it is close to the wall and unlikely to creep further into the room.
Of course the real fun part (cosmic humor) was that my tv does not fit, So the original idea to create a functional station for many sorts of entertainment has a fatal flaw–at least partially, but then I started to consider an entertainment center I had salvaged years ago, but never assembled. And yesterday I played detective and csi investigator, matching holes and misc connectors until I had the whole thing put together in it’s original configuration.
That in itself was a great feat, and the tv fit, but the new old center was in much worse shape than the first one, and would need most of another wall to install, one already occupied with very intense storage. I took the radical step to disassemble and commit it to recycling, even to the extent of removing the quick connector studs and other recyclable parts.
And then I looked again at the storage wall. Numerous mismatched drawers and a couple sets of plastic shelves now partially displaced by the first entertainment center, and, with a rainy day ahead, it seemed the thing to do was to remove it all and build the work bench storage area I had always intended for that space.
So here I am, after taking a break from a quick tour of the ponds after about 3-4 inches of rain -everything working fine- and planting a few more pepper plants and weeding a bit, writing a blog and putting off the next steps which will involve doing an accurate jop on that wall, putting in better quality studs and securing the top plates in a more permanent way. Then it will be time to bring order back from the temporary chaos, the goal being an open work area, with easily accessible storage, and lots of stuff losing it’s place cluttering my house.
and the living is easy. Catfish jumping and the Kale is high.
The grapes aren’t quite at the point of shielding the glass enough or cooling the air enough, so I put up the sheet again this year to keep the sun out of the greenhouse, maybe next year with a better trellis and more growth of the vines.
A couple days ago as I started misc tasks around the house, one of my trips past the fish tank I noticed all the Koi had died during the night.
I have had fish die before, but never so many so suddenly; and obviously, the buck had to stop with me, since there is no one else taking responsibility. I like to be casual with my projects, expecting everything to work out without getting too anal retentive about things, but I need to remember there are some things that need scrupulous care, and my normal “it can wait” attitude needs a little adjustment with some things, especially living systems that depend on artificial support.
Perhaps the issue will turn out to be some rare disease that I had no control over, but right now I’m operating under the assumption that the issue was warming water with warming temps in the greenhouse, and an algae bloom that consumed all the oxygen overnight. Something I was well aware of in theory, but really didn’t understand the practical implications.
The day before everything seemed fine, but I had noticed some murkiness to the water. The fish were doing their normal feeding, competing at the surface for the pellets as I dropped them in the water. The sudden deaths took me completely by surprise, and the shock was even greater when I started looking at replacements on ebay. The money loss was likely in the neighborhood of a couple hundred dollars.
And it all could have been avoided if I had just a little more experience and/or caution. I believe a water replacement of about 1/3 the day before would have avoided the disaster. An air pump would have avoided the disaster. A better filter would have avoided the disaster.
The fact is I got complacent and didn’t do everything I could have done to ensure their survival, and the only consolation is that these are still early days in my fish raising adventures, so I at least will have this failure to learn from. Going into the more expensive Koi I will be inspired to be more serious in protecting them.
The month has been wet and cold, every week seems to be a combination of a few sunny often warm days, followed be several days of wet, sometimes intense rain days, with a couple small episodes of snowfall, but nothing lasting more than a day or so.
The roof has held up fairly well in it’s temporary configuration, and there will likely be no changes made till summer, although occasionally the wind rattles the metal sheets and I cross my fingers .
The increased solar panels and battery bank size have weathered the many days in a row at times with no real trouble. I do treat the sunny days with an extra bit of personal energy to take care of the things that draw the most electricity. Charging my tool batteries, washing clothes, etc, and though they don’t take great amounts of energy or time, remembering to do them in a timely manner can be a challenge, since sunny days I’m more likely to be outside as well.
I discovered this past weekend that my charge controller is not a true MPPT one. This means the 36 volt current coming from the solar panels has largely been wasted, and although I had been planning to buy a new small AC refrigerator to replace the propane one, I decided to scrap that idea and started looking for DC refrigerators in an effort to save money and conserve energy.
Which is the next project, although it will likely be a slow paced one. It will involve getting a new dc compressor charged with the new world standard refrigerant. Isobutane and isopropane. I finally found a somewhat obscure document last night documenting test results from an experiment that replaced freon R134a in a conventional fridge with R600a . It will require a new compressor, and I will try and find a shop to do that for me,(as soon as I find a suitable refrigerator body for my new frankenstein monster refrigerator.
While new dc high efficiency fridges cost upwards of 1200$, the one I plan to put together should cost around 400. It will require about 30% less electricity than an ac refrigerator which requires an inverter, and there should also be some efficiency gains with the new coolant.
After writing the last couple paragraphs I got a new charge controller in the mail, wonderful, it is multiplying amperage just like it’s supposed to, and has a couple of other features I will be exploring, but that is one part of the energy solution here.
The ponds got some more attention over the last few days of the month, everything from chipping up brush piles and general cleanup of the surrounding areas.
On the keeping machinery functional side of things I was able to start and run both chippers and that will help keep gas fresh and carburetors clean.
As a final act with the backhoe in February I dug up the rosa rugosa in the garden, it develops a net of roots underground, and I’m very curious to find out how sensitive it may be to being separated and transplanted. I have about half of the clump still in a big ball of earth just in case the individual transplants don’t survive with the minimal care I’ve given them.
The DSR stove has been performing better since I installed the steel fittings at the hot water exit from the tank. It is easy to take a temperature reading there to monitor the heat of the tank, but the location of the fitting on the side of the tank makes the system a bit awkward in use, and normal operation heating unpressurized water wastes a fair amount of water , and I plan to only use tanks from now on with a hot water fitting on the top of the tank.
The Koi are doing quite well, I feed several times a day, and wait for them to come to the top of the tank before I start dropping in food, and, when they all go back to the bottom of the tank I stop feeding. This means there isn’t extra food floating around, and they are slowly losing their fear of me.
I have a plan to enlarge the kitchen garden pond into a much larger koi pond, but probably in the short term I will reinforce the repairs on one of the smaller preformed plastic ponds and use it for the first part of the summer while their main pond is taking shape. I plan to buy a regular pond liner and really make an attempt to keep the water clear, possibly even have it deep enough to swim in.