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Deagen Demientieff
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Some of you might find this exciting. I have a sony camera and very good video and audio editing skills great for documenting professionally. I am building a earthbag home in North Pole alaska. I have had a horrible time finding clay for this project so will be using other fill material and insulation for the bags. However, I did manage to go down river and find Enough clay for a rocket mass heater. I have bought the books recommended, and read them, I am determined to build one. I have never seen one before in real life. I have never felt the heat from one. All I know about a RMH I have read or learned from his forum and the ebooks. The winters here are VERY cold and can go from 30 degrees to -20 below in just a day sometimes a few week cold spell of -45 -50. With my conventional wood stove I burn well over 4 cords of wood before February. What I am doing and documenting is to see how well this natural building and RMH can withstand the most extreme of cold climates. I would like some guidance from some experienced people here regarding the rocket mass heater. Do you think it can hold up and perform well in these kind of extreme climates? I will be following the basic RMH design mentioned in the ebooks with the 55 gal drum combustion chamber and a cob bench for thermal mass. It is my first RMH and as far as a know the only one here in fairbanks/Northpole alaska. If this whole project works I will be heavily promoting it in my community maybe even starting a permie community in alaska. Wouldn't that be amazing. XD


Also I have friends who have built log cabins and live in army tents with barrel wood stoves for heat while building the cabin .Even during -40 below!As long as the wood stove was running it was warm in the tent. I don't think this would be possible with a RMH. Also a lot of people that I have talked to have said then RMH will never work and I'm wasting my time. I would like to prove them wrong. I want this to work here in alaska so other Alaskans can see we don't have to burn 20 cords of wood a winter or spend tons of $$$$$ on toyo oil heaters or have super high electric bills to be comfortable and warm. If I can accomplish just 1 small successful earthbag home with a RMH and spread the awareness to the younger generation ,maybe start some workshops, I could see permie culture becoming very popular here.
 
Satamax Antone
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thomas rubino
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Hi Deagen; Congrats on being the innovator! when i found out about RMH 's i told all my friends and neighbors about them . They all thought i was crazy, wasting my time ! my green house was going to be frozen the first below zero morning! Well guess what,... they all had to eat crow ! northern montana ,10 below, howling wind no fire in the plastic greenhouse after 11 pm and at 6 the next morning it was 41 degrees ! I haven't gotten a good number on how much wood i used out there last winter , i'm guessing apx 6 cord, on previous winters it was 12-15 cord and hope it warmed up soon. I'm working to much this summer to build my next one out in the shop , but this winter if i'm off i want one between both bays in the shop to warm up any vehicles inside as well as a warm place to sit ! after that comes the one in the house! These things really do work AWESOME ! Don't let anything stop you, you won't be sorry and all your friends and neighbors are going to want to know how to build one . Good Luck and keep us posted with pictures here on permies !
 
Deagen Demientieff
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I was able to get some clay but I fear I won't be able to get enough. I have roughly a 100ib of clay however the river has gone waaaay up due to record breaking rains this month. It probably won't be down again till September. What else could a use to make my thermal battery bench out of? Could I use a lime plaster also? What types of things , rocks steel etc. could I pile into my mass and cover up with a plaster that would be great for giving off heat?
 
Satamax Antone
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Deagen, rocks, plenty of them, and concrete is good enough! imho.
 
Deagen Demientieff
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Could I use a lot of rocks as the mass and do a concrete/lime mix to shape the bench? With a lime plaster finish? What about mixing what clay I have with the mix?
 
Satamax Antone
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Deagen Demientieff wrote:Could I use a lot of rocks as the mass and do a concrete/lime mix to shape the bench? With a lime plaster finish? What about mixing what clay I have with the mix?


Well, whatever suits you.

he only thing to avoid is insulating products for the mass, exept if you want to slow the heat release.

One thing thought, use a stainless pipe when you enter the mass, so you don't have the concrezte flaking off and blocking the flue. May on two meters. Normaly concrete resists up to 400C°, but you never know.
 
Joe Sylwestrzak
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I commend you on RMH for Alaska. Built my first last winter in MI. as last resort after being violated by propane price. A 4 inch J tube into a 13 gallon compressor tank with no mass vented out window pic included. Frigging amazing. Started heating with it when low temp was 30 at end of winter. Heated 1800 of my 2100 foot ranch home on 1/2 milk crate of wood a day. Last 6 weeks of heating cost me 1/2 face cord = 25$ awesome but was not enuf to heat my home in the dead of winter. Today I bought and had delivered 2 55 gal barrels and 60 insulating firebricks to build 1 with mass for home and 1 with heat exchanger for garage. RMH = way less pollution,deforestation and wood cutting. Cant imagine how much work you Alaska guys put into wood cutting. Alaska need this!
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Deagen Demientieff
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Here's an update on the house with a YouTube video and some questions enjoy. More updates soon. The question are better explained visually do watch the video.
I just have some questions about the layout of the thermal mass I have a few options. I wanna make a heated bed/ bench. Enjoy the video




 
Burra Maluca
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I've embedded the video below.

 
allen lumley
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Deagon Demientieff : Short version, your last choice is out, here's why ! With a 6'' rocket mass heater RMH,you get to have 30' of Horizontal pipe to embed in a thermal
mass. That is 30' - 5' for every Elbow in Your system ! A three elbow system is about the best you could hope for, that is a straight run off of the manifold below the barrel,
8' and then use (2) 90 degree elbows to turn around and come back to the barrel and then a 3rd 90 degree elbow for your final vertical chimney straight up through your
roof !

While the RMH is a wonderful heater it works best if you start out with a Blank sheet of paper, put the RMH in the center and then design a house around it !Often starting
out with a house and trying to retro-fit an RMH inside it Sucks!

With this 6'' system you Have to have a rectangular or oval shaped house ! And its not me you need to get to change my mind its Physics and Mother Nature ! You are not
the only one even to be caught in this trap, With a bigger system we could have a few more elbows, but a bigger system would be to big for your space ! Draw up a sketch
of your present structure, and shoot it to us, and we will play with the impossible.

I want too suggest that you go to Rocketstoves.com, to download a PDF Copy of The Brand New 3rd Edition of Rocket Mass Heaters, this will help you to figure
out what is possible on your own, if we come up with some thing it will be a need copy of the 3 elbow set up, so if you want to wait on an answer from your fellow members
here at Permies, before you invest in the book I/we will understand, but you will need it often to understand exactly what we are saying to you if we can save this Build !

You can be sure if together we say we can do it, it can be done, we will not allow the creation of a failed RMH and a Homeless House Dragon !

For the good of the Craft ! Big AL

 
Deagen Demientieff
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Awesome I could just go straight out the back then eh? Just make a small heated bed? Btw Owen Gieger and Allen are my Heros
 
Deagen Demientieff
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I have the book to btw
 
allen lumley
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Deagen D. Up and out Through the roof !We want he very shortest amount of final vertical chimney exposed to the Extreme Cold ! Also It will allow us to configure
the rocket mass heaters RMHs burner base and Thermal Mass to the smallest possible space !

Right now I need a rough idea of the size and shape to put down on paper here, and your more carefully figured follow-up sketch of your interior!

Let me be a little more clear, and see if I can earn a little of your trust, At the very bottom of this page locate the permies >> forums >> energy >> rocket stoves,

click on the rocket stoves the next page lists all Rocket Stoves Forum Threads, most recent 1st, find the Thread labeled

:::--> video:great rocket mass heaters in upstate N.Y. and Quebec and click on it, It is the 1st video I want you to watch.

The house and the RMH custom made for it are both to big for your use, I wanted you to see the backrest on that daybed and see that we can shrink the footprint
so that you can recline on a slightly Lower shelf ( For Safety), with your head high enough to easily monitor your flames at the Feed Tube and easily reach out and
drop in another piece of fire wood !

This will use up the smallest amount of space, center our RMH and give you 360 degrees of Travel around the outside of the 6'' RMH, and the inside of your House !

For the Craft! Think like Fire! Flow like Gas! Don't Be a Marshmallow! As always, your comments and questions are solicited and welcome! Pyro-logically Big AL
 
Deagen Demientieff
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Cool Allen i liked that video it was very inspiring. I'll make a sketch and post it. I need to get into rmh mode. All summer I've been in earthbag mode so now it's time to do this and get it working. Then finish the house. More updates soon.
 
Deagen Demientieff
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Well I until I make a sketch I could tell you the structure is 14x14 with door on the east and a window on the south. There will be a upstairs. The rmh should go downstairs there are inner buttresses. One on the north wall an two on the west wall. They stick out only about a foot and a half. Maybe less. So I can position the rmh in the square. I can change the interior structure a bit as long as I don't have to tear earthbag walls down. Also the outer walls with have insulation so I can use the thermal mass on the inside and protect the bags from extreme cold
 
Deagen Demientieff
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Here I just drew this rough sketch up right now. This is the current plan. Tell me what I need to do to make his work I was hoping to make a heated bed to lay on.
image.jpg
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Deagen Demientieff
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B=buttress the extra squared connected on them is the bags that step down off the top buttress. They make a enclosed area I was going to use for storage but I thought I might be able to make a heated thermal mass there. I can Change this and go back to using it for storage if need be. I really don't wanna move the buttresses.
 
Glenn Herbert
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Is the 14' x 14' interior or exterior dimensions? I would think interior, as wall thickness would make the other possibility miniscule inside. Even a 14' interior dimension renders the corner mass placement the only reasonable choice given the buttresses.

If your sketch of the stepped north buttress is accurate, you would probably need to send one or both of the flues through the buttress, where the heat would damage the earthbags' exterior wrapper. You will need to replace some of that material with heat-resistant material at least for the first penetration from the barrel outlet.

Integrating the buttresses with the thermal mass would make sense - let the heat get into those as well as the bench and it will be comfortable to lean up against.

 
Deagen Demientieff
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14x14 is the interior dimensions. The northern buttress steps down enough for the flu. If i lime plaster over the bags will that protect them from the heat? Or should I use cement over the bags?for where the heat will touch the bags? Should I just use the that corner of the building as my single mass and have my ducting and clean outs run through it then up through the roof? Or out the side of the house? Near the roof?
 
allen lumley
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Deagen D. : In no particular order, If we build everything into the north wall you are going to promptly dedicate 20-25%
of the total floor plan to Your RMHs build.

If You can accept the placement of Your RMH in the center of your mass We will actually use Less floorspace about 15-20%
and have better radiantheat distribution everywhere else !

You will need to do a soil sediment test, to determine the % of clay in your soil, Google -fu also a test to determine the
workability of your clay. I understand that many skim coats and lime washes have portland cement in them, it is there as a
readily obtainable way to stiffen the mortar/wash mix and make application go better, I personally have a bias against the
high energy costs of cement, and have avoided using it and have
zero experience with it, However we will get you at least a couple of working Recipes.

If you look at the RMH video I showed you earlier, at about 2:00 there is a good look at the long axis of the RMH, mostly the
day bed and lounging side! If we keep the location of the feed tube barrel axis the same and come out of it about 4' then use
an elbow and a short length of pipe and then an elbow we can turn 180 degrees and run along side of the Barrel and feed tube
and have a sitting area and then a day bed.

Given your inside dimensions a diagonal line drawn from the northwest to southeast is ~19' 9.6''~ I propose to install your RMH
some where on that line.probably with the day bed / lounge on the door side and able to see the window !

Assuming that you have no major broken bones to bake at the fire, I am assuming that you will want your dominate/stronger
arm on the inside close to the RMHs feed tube, here the test is your muscle memory, in which hand do you normally hold a drink!
By anticipating things like this we elevate our RMHs build from something you like to something you love!

If we think of the total shape of the RMH less the thermal mass generally we would call that shape a Keyhole, or say its shape
was close to theoutline of a Edison based incandescent light bulb !

The thermal mass in the video is like a big Pork chop kind of wrapped around the keyhole. The bone side of the pork chop clearly
represented by the backrest/spine shown in the video. The meaty part of the pork chop makes up the day bed position in the
video. we will be using a similar layout just a different cut of meat !

I assume you have a plan for visitors using the loft space and a little thought must be given where we run the final vertical stove
pipe up through that space and out thru your roof, but our total budget for elbows is 3 and we Must stick to that, we can move
the location of the RMH around in the House until it is actually built!

Look at the video again , try to think of the questions raised and get back to me ! for the Good of the Crafts Big AL
 
Glenn Herbert
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With a 14' interior dimension, a 6' long daybed would leave only 3 1/2' on each side all around it, NOT counting buttresses on two sides... essentially making it occupy the entire center of the room with barely enough space to move around it and have anything else at all in the room. If you want storage space on this level, you might put in a shallow closet in the NW alcove you identified and move the daybed just out from it, allowing a door/walkway at one side of the daybed. Letting the back of the daybed be against a wall gives much more flexibility in floor arrangement. If the bed is built against the north buttress and incorporates the steps inside it, that part of the impediment will go away. How big of a bed surface were you wanting? Enough for two, or just one? Given the space it seems it should double as sitting area with a back.

As a thought experiment, if the W end of the bed is 3 1/2' from the W wall, that leaves 2' to get between it and the W buttresses into the closet area in the NW corner. A 6' bed leaves 3 1/2' clear to the E wall. If the back incorporates the buttress steps and leaves a useable storage space behind it, it will be 2' or say 2 1/2' from the N wall. Assuming 3' depth including backrest, that leaves 8 1/2' clear to the south wall... not a bad distance for radiant heat to reach.
The bed (centered on the N wall) will have about 2 1/2' x 2 1/2' alcove behind it considering buttress thickness. Maybe the barrel can go in that space (slightly adjusted for clearances etc.) with the feed tube peeking out from behind it, arranged to be convenient to reach from the bed/bench. The 3 1/2' wide alcove left in the NE corner should leave enough space for some indoor wood storage as I don't expect you want to have to go outside more than once a day to get wood. It would only be a couple of feet from the door.

A paper sketch would be good at this point, to fully grasp the space potential. Draw a uniform 1' grid first to help with layout and keep you honest
 
Glenn Herbert
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Another notion: Given the duct run restrictions counting elbows, and the tight space, you might not be able to fit enough 6" duct for good heat transfer. Look at Matthew Walker's "half-barrel bell" concept - it can dramatically increase the heat transfer area and reduce friction losses while fitting under a bench.
 
allen lumley
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Glen : And the last shall be 1st, and the 1st shall be last ! I really like the idea of 1/2 barrels, which Should be do-able in Fairbanks, just a little into the country
that may be a problem ! Why don't You P. M. Him and see if he wants to join this conversation !

With a 14' X 14' cabin the diagonal axis is 19' 9.6''-ish My propose all is to center the mass, otherwise Double D's room will shrink to 10 by 14 with more space
unavailable!

I am missing your entire point about the buttress steps, but perhaps you got a clearer look at the cabins interior than I did !

Deagen find som graph paper and do something to scale, right now we are just eliminating what you cant live with, But, we are running out of time !

For the Good of the Craft ! Big AL
 
Deagen Demientieff
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Ok I will make a better sketch and get some good interior pictures next time I go out there so I can take some measurements. I am not opposed to changeling the interior at all to get optimal space and efficiency. As for clay% it's zero. There is no clay on my area it is rare and I had to take a boat on the river just to get a little bit for a small pizza oven I might make later. So my mass will have to be made of mostly stone and cement/lime. I don't know when I'll be out there next but I'll try to get out there tomorrow morning to take some pictures and measurements and make a sketch
 
allen lumley
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Deagen D. : Regular concrete made from Portland cement, all imported, (for you, mostly it comes from So. Korea) starts to fall apart at temperatures above

400dC.

The internal temperatures of the Combustion Core are above 1100dC, you can not use Concrete within the Keyhole footprint of the RMH !

You can do a google search for more information or just search for this information from your neighbors the Cold Climate Housing Research Center, an arm
of the University of Alaska Fairbanks! www.cchrc.org While looking at the cchrc.org site please remember that there is a boat load of steaming crap
out there in U-tube land, I sent you to cchrc.org because I trust them, I know Cold, They KNOW COLD ! !!!

No clay, no RMH footprint, you can buy it as a 50 lb, bag and will probably need 3 bags of 'Fire-clay' probably shipped up from the states ! If, you want to go
that route !

Also, I have to give you some home ork, which requires you to buy the text book, You need to goto rocketstoves.com and download a pdf copy of the
brand-new 3rd Edition of Rocket Mass Heaters, this is a must as we get to the heart of this build ! 4 the craft Big AL
 
Deagen Demientieff
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Nice Glenn I checked that half barrel bell idea out and it looks like a great idea if I use 2 10" ducting. I also like how the mass was filled and elevated off the floor with forms. As for not using cement I'm all for it. I know I can use gravel and rocks and sand for most of my mass. Could I cover that in a lime/sand plaster mix?
 
Satamax Antone
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Deagen Demientieff
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Using barrels instead of ducting takes up more room and provides less space for mass. However don't the barrel bells get hotter? Is the draft pull better? Does the thermal mass heat up faster when barrel bells are used rather than ducting? I def have more barrels than ducting available.
 
Satamax Antone
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Deagen Demientieff wrote:Using barrels instead of ducting takes up more room and provides less space for mass. However don't the barrel bells get hotter? Is the draft pull better? Does the thermal mass heat up faster when barrel bells are used rather than ducting? I def have more barrels than ducting available.


Deagen, it's dead simple.

Exchange time and exchange surface.

Mass can accumulate more calories, or BTU's than you think. If a mass heats up at 120C° instead of 60C° it stores twice the power than at 60C°

Let's compare an 8 inch flue, to an55 gallon barrel of equal lengh.

Let's say 20ft long.

8x3.1415926 =25,1327inch. X 12 x20= 9047.78sqin.

A barrel is 22.83 in diameter.

So, 22.83 x3.1415926 = 71.72 in. /2 for a half barrel =35.86inch plus 22.83inch for the base. =58,69" x12 x20 =14085sqin

So it's about 1.55 times the surface of a 8 inch flue. Well, in both case, the whole heat exchange surface is not active, and there's differences between round and half round. But there's differences in the heat exchange surface.

Plus the cross sectional area is different. 8x8x3.1415926 = 201.06 sqin/4 =50,26sqin x12x20 =12063 cubic inch for the 8 flue

Compared to

22,83x22,83 x3.1415926 /4 =409,35 sqin. x12 x20 =98245 cubic inch /2 for a half barrel =49122 cubic inch

So it's about 4.07 times the volume. So gases slow down in there about 4 times.

If the flue gases have 1.55 times the surface to exchange the heat, and more than four times the time to exchange it. You bet it's more efficient at transfering heat into the mass. Even if there's less of it to store the heat. It will heat up far more. Andfurthermore, since the half barrels can be used as a bell, gases stagnate in thoses, so exchange time is even more increased!

Get it?

Hth.

Max.
 
allen lumley
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" Max" : I know where you are going, but I got lost on the journey there, THE Inside Surface Area is sometimes just an extension of the units CSA, but sometimes
its like the other side of the coin! I Always say you don't know the subject ,if you cant explain it to your grandmother ! Give ME a little time to review CSAs and to
attempt to get my head around this, and Lets see If I can get It right !

For the Good of the Craft ! Big AL
 
Deagen Demientieff
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Ok so idk when I'm going back out there to the earthbag house might not be for another week. I can use barrels but I need to use something natural to take up most of the mass rock or silt or gravel with sand?. I can order a clay plaster from American clay or somewhere to give it a nice finish if I can't use lime. I'm doin a lime/sand plaster over the bags so if like to do that over the rmh if I can to match it but not for the bulk of the rmh.
 
Satamax Antone
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allen lumley wrote:" Max" : I know where you are going, but I got lost on the journey there, THE Inside Surface Area is sometimes just an extension of the units CSA, but sometimes
its like the other side of the coin! I Always say you don't know the subject ,if you cant explain it to your grandmother ! Give ME a little time to review CSAs and to
attempt to get my head around this, and Lets see If I can get It right !

For the Good of the Craft ! Big AL


Internal surface area (ISA) and cross sectional area (CSA) are not related (much!)

We know so far, that a 6 inch batch box can whistand a single bell made of mass; of 6m² ISA (64 sqft) , the floor is not accounted for, if the bottom of the intake and exhaust are at three inches or more from the floor. You reduce that to 5m², if you have a metal bell.

If you have a double bell, you reduce the total isa by 15%, and by 35% if you have a triple bell.

A 6 inch J tube can whistand 3m² ISA aproximately, on top of the 1.8m² from the barrel. That's suposedely an absolute maximum with a good drafting chimney.


I should say CSA and ISA are loosely related. You need the first one, in conjunction with the type of core, to decide the second.
 
Satamax Antone
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Deagen Demientieff wrote:Using barrels instead of ducting takes up more room and provides less space for mass. However don't the barrel bells get hotter? Is the draft pull better? Does the thermal mass heat up faster when barrel bells are used rather than ducting? I def have more barrels than ducting available.



Well, i didn't adress that.

the answer is yes, if the barrels are used as a bell. A taller bell has less friction than the half barrel system (invented by Matthew Walker) But the half barrel system has less friction than an eight inch flue for example. All due to the boundary layer and laminar flow.

For example, if we were making a cubic bell of the same volume as the half barrel 20ft long bell described earlier.

For 49122cubic inches, we have a bell of 36.62 inches per side. (root of three or third root?)

That means, not accounting for the floor, we have 36.62x36.62 =1341sqin X5 for the four walls and ceiling, =6705sqin or 46.53sqft of ISA, for 36.62 inches of travel.

Compared to the 14085sqin of the half barrel system described earlier, but traveling 20ft in that case.

You double the height of the bell, and you're nearly at the same square footage as the half barrels.

In the case of that 36in cubic bell, we're at about 2/3 of the surface of the 8 inch flue, but for only 1/7 aproximately of the travel. And most of it is friction of gases on gases. Not gases on stalling gases stuck to a pipe wall.

So, as long as you haven't exceded the maximum isa (which is given by the condensation point) where all the gases stall in the bell; a bell lets the draft pass better than an horizontal flue.

About Matt's half barrel system, there's also a trick, down low intake and exhaust of the bell, but at the same end, for less travel That's called a dead end bell. And can also be done with a brick bell or else. As long as the floor surface area is 4x the CSA.
 
Linda Cozzini-McKirgan
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Deagen Demientieff, how goes the project? Our Fairbanks RMH is coming along with some design adjustments. We are using a front feed with fresh air supply and a sealable door.
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Deagen Demientieff
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the building has come to a halt for winter. Im renting a cabin now and i go out to the earthbag house occasionaly to check on it. Cant wait to start back up in may! This is a really fun and rewarding hobby! Linda? thats a good looking rmh with a batch box. Are you currently living with it? Its been a warm winter so far.
 
Linda Cozzini-McKirgan
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Hey Deagen,
We are using the heater as we continue to add mass. It is a crazy warm winter, so it is hard to compare energy costs with last year...no complaints.
It will be cool to see your project continue in May.
Some of my middle school students said they saw good clay by the new Tanana recreation area this summer? I ordered some extra clay from Oregon to continue with my bench.
Take care, Linda
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Deagen Demientieff
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THis is just great linda !! Would you like to meet for coffee?
 
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