Thanks Peter, I think Ill add that in as I was already identifying that as an issue. I wasn't initially sure about the spacing, but I do have it at 2.5 inches so that is pretty darn close.
Peter, not actually much at all. I tossed it or else I would post a photo, but I would say it deteriorated about 6mm at the most. It wasn't much, though with my house I was only burning about 2 cords a year.
A huge thanks to your ever handy proportions table which I've used probably a thousand plus times in these last five years.
Those interested, the floor channel is a product of https://dragontechrmh.com/ and uses the RA330 stub which shouldn't deteriorate anytime soon. I'm also going to be building a 6" batch in a friend's house soon and will document and post accordingly.
Because I'm here typing and didn't see it any other place, what is the recommended floor space in the batch between the main air inlet and the floor channel where the cool air pools? Have the greater RMH minds figured out a percentage for that to use between different size stoves?
Yes I don’t think the half inch will greatly change it. Mine went from 13 to 11. The 15% reduction seems to have made much more of a difference. I’m going to let it cool down a bit more and the cut the port two inches taller.
Hey just wanted to share my conversion of my batch rocket 8”. I originally built this stove 5 years ago and it has ran very well with a p-channel in place.
However this year I decided to replace the barrel oven door with a nice glass door and at the same time take out the p-channel and replace with a floor channel.
Finished up the door and cob last night and did a test burn this morning. This is when I realized that I forgot to adjust the port height after the floor got raised!
Ran the right direction but wasn’t the cleanest of burns to say the least. I’ll make sure to report back once it modify the port to the correct size. Anyone else have info from their conversions?
I'd just throw one together out of brick, or take some fun time to make one out of cob. You can usually find the materials for cheap/free and have something that works better than the one you are looking at.
Honestly if it has holes and gauges in it then it probably wasn't well finished and was too soft. I would say take the finished layer out and see what you are dealing with. It is possible a membrane didn't get used, or maybe not a hard enough oil.
I feel like that video was the equal to a mike drop.
It's funny that this should pop up as I just recently discovered this by testing it out myself last week when it was in the 90's during the day. I've been sleeping in my 150 square foot strawbale shop that has a 6" J and after I accidentally forgot to close the windows for the day, I came home only to discover it was stupid warm inside! Then the thought came to me, maybe as it cools the rocket stove will draft the hot air out! Not a new concept obviously, but i can attest to its effectiveness. The barrel and mass were exceptionally cool in the morning as compared to other nights when I had only had windows open.
Back to the original post, I'm glad you posted this Paul as we have the green homes tour in the Bitterroot coming up and one house as a heat pump vs another that has an 8" batch. I'm sure this will be a question.
A great practice. I have a local who does this as a course at our local library. I provide notebooks and coloring supplies, she provides the instruction and they go to the park.
Hi Molly, I have used canvas, old carpet, and tarps for mixing. The problem with the canvas is the same as the carpet, they get pretty heavy with water by the end and break down fairly quickly.
I know using plastic isn't always nice, but if you can get your hands on some vinyl billboards they will go a really long way. I got some free from a local advertising company that are approximately 12x24 feet which makes 3 or 4 really nice stomping tarps. They are still in use even after three years of cobbing on them as they are much stronger than the cheap woven blue tarps.
This past week we had an awesome group come out to Victor, Montana to learn how to build with earthbags, bales, and cob. This was our first natural building intensive class and had ten participants for 9 days!
In the next few months we will be working on finishing the plaster, installing a 6" RMH, and pouring earthen floors. Check out our website for details how you can join us on these projects!
Hello everyone,
While I'm a long time poster at Permies, having frequently posted projects I've been working on, I thought it would be appropriate to add a dedicated page to all of our happenings in the Bitterroot Valley, Montana.
For more information about how to attend classes, who we are, or how to contact us, visit SpiritWood Natural Building
Trace, that is some great results. Great job sticking to the cold--it is a pain sometimes for sure but I swear it is worth it just for the mental exercise.
WHM practitioners call those shakes "after drop". Try a mental visualization afterward of breathing in hot air and exhaling cold air. This kind a visualization is akin to placebo, using your mind to make adjustments to the physical. The times I get after drop are after cold exposure when I'm not sufficiently concentrated enough on heating myself up, but go on to the humdrum of my normal routine like doing dishes or thinking about house improvements.
Would you mind sharing details about the cold showers? Curious how long you do it for, how many times a week when you started, how long it took you to get acclimated, those type of things.
Definitely. The cold showers are the way to go because you don't actually need to be that cold to reap the benefits. I love hot showers, so I start hot to relax then after a few minutes switch the taps to cold and stay there for at least 3 minutes. By that point, any increase in heart rate and feeling of dread is gone. It takes a good week of daily practice to get to the point where the cold water doesn't bother you too much anymore. It is an interesting thing, because your brain still says "no!", but the water ends up not feeling that bad any longer. A WHM instructor once told me that you don't get as many benefits if you finish on hot, but instead let your body warm itself up so I never finish with a hot shower.
When I soak in the pond I tend to stay in longer, about 5 to 10 minutes--just a different experience with the trees around you and not that rushed feeling of being inside.
So in summary I take short 3-5 minute showers 6-7 times a week, cold soaks in the pond 1-2 times a week, and the breathing exercises for about 20-30 minutes every morning when I wake up.
great to see this thread. I've been practicing the Wim Hof Method for almost seven years now and it is fantastic. I hit my pond often, but do cold showers daily coupled with the breathwork that Wim is known for practicing. Keeps me cold free (both temperature and sick).
I'll state up front that I am a big supporter of ADA. The idea behind crypto is a sound one, especially with companies like ADA who are focusing on building smart contracts and cutting out banking systems.
As for NFTs--I dont see much of a purpose really other than digital collector items. We all have things that we collect--I have several decks of permaculture playing cards that have not been opened.
Look at NFT's for what they are--they are a gimmicky perk that would help raise money for other ventures.
And basically anyone has used their apples to make discounted purchases through vendors listed on permies already has a basic understanding of crypto. You "paid" permies.com with knowledge instead of cash, and earned an alternative to money.
Behold the worlds tiniest rocket mass heater. I printed this for my daughter to play with to incorporate into her doll houses and such. A to scale version of the 8" batch rocket at wheaton labs. The system size is 2.5cm if anyone was wondering. Barrels are removeable for riser inspections.
Thomas, great thinking of the kiln shelf. I checked with my coworker who is a long time potter and she had 12"x24" shelves that have been pitted from the glaze she uses to give me for free. Excellent! I'll post a photo of the new 8" I'm working on next weekend.
Hi everyone, a recent post made me curious as to what everyone has used (successfully and unsuccessfully) for their batch rocket mas heater lids. This would be the material used to span the box of the rocket mass heater.
I can attest that a thick cast iron griddle has been working well for four years of burning in an 8".
A friend has a sheet of steel on his 6" batch with a layer of superwool protecting it.
I feel like I've seen bricks being used for smaller systems, but for the 8" brmh you need to span that 11+ inch gap.
Would a thin board of ceramic fiber board be strong enough? I'm inclined to keep using cast iron as it can handle many years of being knocked by wood.
So I’ll second what Peter had mentioned just to make sure it is noted. The pipe transitioning the barrels to the bench is too small in diameter. I believe this should be 1.5x the diameter of the stove or bigger. I’d shoot for this transition to be around 10” in diameter or else it will restrict the flow. I’m on my phone so didn’t open the sketch up but this transition should be at least 4” from the bottom of the barrel to allow the gases to exit on all sides.
Piped masses can be done but add friction to the gases. Much easier to stratify and get all the heat without running it through a pipe. Also it is harder to total the ISA of a pipe versus bell. The pipe doesn’t stratify so only the top 2/3 actually count. Peter’s math on the brmh site was done for bells. Again, not impossible just adds a lot of unknowns.
Hi everyone, I am shortly going to be building another 8" batch rocket in a strawbale house. I have not done a floor channel, only P channels in the batches I've built.
I understand that the floor channel is much easier to replace later on, but after I watched Matt Walker's video on his floor channel design and he said that he was needing to replace his vertical piece every year--???-- it made me wonder if the longevity of the p channel is worth it.
My P channel on my batch rocket has gone through three years without any serious degradation. Why are Matt's floor channels wearing down so quickly? And what are your experiences? Is it from smacking that vertical piece with wood? Is it that much hotter at that section of the port?
Peter covered most of everything I was thinking. I will just add that I did a cooktop on the firebox of an 8" batch. Used a cast iron top which has had no problem after 4 winters, but it tends too get too hot for anything but a kettle. Also at a terrible height for people to get burned. I have a three year old and have subsequently insulated and cobbed over the cast iron.
Here are some photos of a little 6" J we built this year for our strawbale guest shop. The core was built during a one day RMH class. I double stacked the barrels to create a large enough bell as we didn't want a full bench. Temperature of the barrel is about 500F and the exhaust is leaving at around 140F. Probably the prettiest one i've made to date.
Hi Becky,
I do similar programs at my library in Montana--am planning on a summer of homesteading during 2023.
Some of the ideas I have tossing around are:
Composting basics
Cheese Making
Raising Chickens
How to butcher
solar panel basics
beekeeping
I'm not sure where you are located, but many of these programs I have sourced for free from knowledgeable individuals who were happy to come in and spread knowledge or drum up business for themselves and their farms.
On another note, many of the videos you are thinking about presenting would fall under "educational" and do not necessarily need to be licensed to present at the library.
107. Limitations on exclusive rights: Fair use
Notwithstanding the provisions of sections 106 and 106A, the fair use of a copyrighted work, including such use by reproduction in copies or phonorecords or by any other means specified by that section, for purposes such as criticism, comment, news reporting, teaching (including multiple copies for classroom use), scholarship, or research, is not an infringement of copyright. In determining whether the use made of a work in any particular case is a fair use the factors to be considered shall include-
(1) the purpose and character of the use, including whether such use is of a commercial nature or is for nonprofit educational purposes;
(2) the nature of the copyrighted work;
(3) the amount and substantiality of the portion used in relation to the copyrighted work as a whole; and
(4) the effect of the use upon the potential market for or value of the copyrighted work.
I think your main concern about the bags sitting for so long is valid. The material going into the bags needs to have an adequate moisture content to get them to conform and set properly, if the material sits and dries, even if you retamp, it won't necessarily be the correct consistency for a strong brick. The labor on bagging isn't horrible. Instead you could fill enough bags to do a single layer, then lay and tamp. Use the machine to lift the bags for higher on the walls and save yourself the lifting. If UV is a major concern-get good uv protected bags and after you do two feet, spray with a clay slip to help keep the sun off.
Bags take some unique muscles to get them in place and tamped. If you've never done a building, bagging and tamping sucks for about a week, but then your body begins to figure it out and it you'll be doing double the number you could the first week.
Hi everyone, thought I would plug an upcoming cob pizza oven workshop in Hamilton Montana. Check out the link posted as we partner with O'Hara Commons non profit in Hamilton Montana. The workshop is July 16 and 17. pizza oven workshop
Also, I've attached some photos of another oven recently built. We did an urbanite foundation and used insulation blanket for the insulation. Oven temps are around 1300F and the outside shell has gone as high as 68F. Makes great pizzas!
Hi Rich,
basically there are two types of popular systems in the RMH world, the piped bench and the bell. The piped bench uses ductwork to run the RMH exhaust through high mass which sucks up the heat and releases it into the space. A bell system works differently in that you have a much larger open cavity that the exhaust pools in and stratifies with the hot gases on top and the cooler gases below. This system can be ideal for spaces where a large mass bench is not possible. A bell can allow you to build vertically with a thin shell that will release heat more rapidly than a mass bench. Check out https://permies.com/t/102393/Horizontal-bench-vertical-bell for more discussion on this topic.
I've seen two portable clay plaster structures. The first was in the UK and I cannot for the life of me find it again, but the other was done by the Canelo project. https://caneloproject.com/projects/tiny-house/
I haven't seen it in person, but it is a beautiful structure.
My immediate thought would be that the plaster would crack with any sort of towing, but Athena Steen is so experienced, she would know best.
Hi everyone, we have an earthen floors workshop coming up in April I thought I would share. This is a collaboration project between Spiritwood Natural Building in Victor, Montana and Sage Oasis Retreat Center in Hot Springs Montana. Check out the info and links below!
Date: April 22-23, 2022
Cost: $75-$125
Location: Sage Oasis Retreat Center, Hot Springs MT
A candle isn't going to throw off much heat. That being said, a butt warmer really doesn't need much does it? Unless it was in direct contact with the seat it wouldn't do much warming. Seems a lot of work to keep the goose pimples off your bum.
After 3 stoves and 5 barrels, I've done away with trying to burn away the paint. I've used the pocket rocket method, sanding, blowtorching and I'm always left with an unsatisfactory level of paint and/or sooty residue that takes way too much time to remove. The last two barrels I did, I just took into a car detailing shop and had them sandblast. Costs 35 bucks per barrel, but saves me an entire day of cleaning and burning.
Hi Betsy, my house is built with a rubble trench foundation with layer of insulation on the outside of the foundation to prevent heave. I believe in MN you would need the apron to extend out from the foundation 2 feet, but I would double check. With a shallow trench foundation you are relying, I believe, and someone please correct me if I am wrong, relies on trapping the heat from the stable earth temp and the heat produced from the house. Even with some insulation you are going to have heat loss to the ground which is actually positive for those cold winter days when you are preventing frost from ruining your foundation. The rubble trench is also superior in that it wicks moisture away from under the house. No water, no frost, no heave.
No concrete slab is necessary for your construction of an earthen floor. Just level, put down 4-6" of gravel, use a moisture barrier, put down rigid foam insulation, do a base earthen layer (quarries have road base that works well), then do a finish layer of earthen floor that gets oiled once dry.
