Excellent job with the stove and the peek a boo window. I knew that the clear pot lid was going to end up on the floor. That glass is rated for maybe 600 F. You have been quite inspiring to me as I have been working on a stove very close in design as your own. I poured my core more than a month ago and I've been working on the rest of the layout of the heat exchanger. My difference is that I added wax tubes and jets for the secondary air and tertiary air and the intake for them come out the bottom of the riser. I fired the core in a makeshift kiln last week and removed the wax and string from the air ways. That way I can draw the preheated air from the air chamber below the heat exchanger. They both have their own adjustable air ways. The firebox will also have its own adjustable air way. So three separate valves to control the air flow that will be under the heat exchanger. I might have to add an experimental window to see how things flow before I finish building the top for it. When I get done, I will include pictures and videos. Thanks for the great ideas and plans.
+James Gulrich Hi James sounds really interesting what you are doing I love seeing new designs and improvements. I sort of knew the lid would die horribly only got around 5 mins out of it before it went. I have to keep saying to myself dont get involved in stoves as I have many things i want to do but its difficult when its in your blood. Cheers.
I want to open a business with you. We have been doing this for over twenty years. There are many different interesting developments. We do not have opportunities like your country. Look at our coal-fired boilers. According to our technology, coal burns much cleaner than gas in other boilers. We can apply electronics to this technology, as in modern cars.
Best Rocket Stove video I have ever seen. Well done! I plan to start building one using some of your methods next spring, but I want to use water as a thermal mass, and then pump the water through radiators attached to the central heater to heat the house. I want to use an Arduino for temperature control, to turn on water pumps and fan, and to open and close the air intakes automatically. I think it will be a fun build, and hope I can post vids next year.
+MindVaccine Thanks mate, no reason why your system wont work, once you get the water up to temp it should be easy enough to maintain by the stove. I would try and make the water exchanger as big as you can by maybe fitting jackets to the inside of the rocket exchanger, I had a thought about fitting small radiators to the inside of an exchanger and linking them together with iron pipe fittings to form the jacket, I dont think they would deteriorate as the inside of the exchanger on this stove has not suffered at all. Cheers and look forward to what you come up with.
Can you please tell me if you could make two stoves into one ?? Take a wood stove and attach it to a rocket stove so that it would burn for 8 hours so one can sleep ?? Thanks
@@LozHarrop Loz, do you think you could find out somehow ??? This is not my area of expertise. Thanks also fella. One last thing, Happy New Year seven days late.
Why not making hole in chimney tube, as neostove can, each hole with a short tube, oriented 45° (as vortex A.V.E.C. -search french quant'homme forum ). Also try cast iron plate, or someting like that (refractory brick) curved (watch samourai carpenter, stone), placed in fire chamber at basis chimney. Dragon stove seems making vortex (concentrating heat-fire on curved plate). -had to do a video of brick BBQ, but only just test- Have good automn.
А планета Земля-то .... КРУТИТСЯ-ВЕРТИТСЯ!!!, - "look into the burning riser" и увидишь по факту действие силы Кориолиса. (And Planet Earth .... cool, turns!!!, - "look into the burning riser" and see.... )
is there any science similarities between N of the equator toilets flush in a counter clockwise direction and below eq toilets flush in a clockwise direction......any relationship to riser vortexes? thank you! and admire your knowledge
d koshman that is a myth water does not i repeat does not spin in any particular direction wherever you are on earth its only the direction the water enters let`s say a toilet bowl sink tub try it in your kitchen sink
+Mike Nestle No Mike if it was incomplete there would be plenty of smoke coming off this is a very clean burn once the stove burns off the gas this does burn with a more blue flame.
thank you Pete, is it?would u please comment......is there any relationship between cubic ft. size of fire box, regards chimney pipe flue size ?thank u so much..I super enjoy your videos and knowledge.
+d koshman No mate my name is not Pete lol ...There is no real relationship and alot depends on the type of firebox too but say your flue is 6 inch you can make your firebox 9 inch and should not be a problem dont go too high with it though and never more than half the height of the exchanger in my experience. Cheers,
Smat system. What temperatures are developed in the riser? When the primary air is off what causes the gas from the wood to migrate to the area of burning?
Thanks, the riser base will be around 700C-800C on a full burn, the heat from the riser pulls the gasses from the firebox you do need a small amount of primary air to keep the flow fed or the fire dies out eventually.
Remove that small kaowool trough, and build/weld in a slightly bigger trough out of 5x30x30mm angle-iron around the inside of the top of the main body of your stove, and then fill it with iron-sand. Then weld a 5x30mm flat-bar standing on edge, on the underside of your square lid, so that it will fit centrally right around the 5x30x30mm angle-iron trough, and the iron-sand will seal it, whilst still allowing it to expand and contract, independently of the main body of the stove, and this also allows for easy removal/replacement of the lid.
Thanks Paul, Nice method that to seal the top. Ive actually had no problems since I welded the plate underneath properly, and i have learned i dont need to burn the stove at crazy heats, i just burn lower temps now and the workshop is still nice and warm. Cheers
Great set of videos progressing to this. Look at the following reference: bioenergylists.org/stovesdoc/Ogle/nordicarocket.pdf. They looked at stoves in various configurations. One of the observations was that the oxygen conversion (ie less O2 in the stack gas) was better as they lowered the pot closer to the top of the riser. The conclusion was that this reduced flow and allowed the slower burn resulted in a better burn out. This is in line with your throttling the primary and going for secondary burn of gasified wood gas. Nice job all round.
+Rex Zietsman Thanks Rex, read through some of the document less gap over the riser does slow down burn and increase temps at the top of the exchanger, while a bigger gap puts more heat into the sides of the exchanger sort of in line with their pan tests. but as they found not enough gap causes the fire to stall, causes problems with many builds as the fire then burns out of the batch box. Cheers.
Like the secondary air idea. I notice at the time of the filming it draws air from the shop instead of the outside. I gather because you where not finished yet. yours is the first I have seen with a completely enclosed firebox that prevents living space air from being vacuumed out the heater. Thus working counter productive. I like this design.
+Q Az Thank you, yes the intention was to have the stove feed from outside air supply preventing draughts inside and pulling warm air from inside, my intention (not done yet!) is to connect the sec air to the outer air feed on the outside of the air control damper so it can run independently. This is the reason the feed intake box was extended so far to the right to connect the sec air pipe in. Hope that makes sense. Cheers.
I noticed all your connector tubes are square or rectangular, can one use a round pipe ( 6-7 in. approx. ) for the connector tube from fbox to the riser tube ?? thanks!
I thought it was burning cleaner before the secondary air was used. Is there any reason not to have both air intakes open? Has anyone tried adding a preheated secondary air to the top of of the internal pipe. so inlet 1 would burn the wood, inlet 2 would burn any unburned gases. Taking this a step further has anyone tried having 3 burn chambers all feed with preheated air?
It probably burns TOO hot with the primary and secondary air full open/on at the same time. Obviously there has to be some primary air to burn the wood initially, when it is closed down, the primary air isn't COMPLETELY cut off. The secondary air really helps to burn off the smoke/woodgas produced in the firebox to give it a very efficient smokeless flame in the end. Get as much consumption of all fuel as possible.
Interesting videos. In the end of the video you mention you want to weld some fins on the stove to extract heat from surface of it. Who don't use the convection principle? You could put a piece of sheet metal around the heat exchanger part and put it so it has 1 inch clearance. Then the air will start to rise between the surface of the stove and the sheet metal. It will make a circulation of air in the room and distribute the heat much better into the room.
cast riser is your draw issue, not that it is a real problem for your use. if you had used a lower mass refractory with perlite, rock wool or light fire brick would help keep the heat inside. secondary air wouldn't be required.
+don ratcliff Hi Don, agreed when the riser is really cold it needs a bit more effort, but if the wind is blowing it makes no difference as the draw is really good.
i watched the videos of you making the rocket stove but not until now did i find this one!!! i love this stove and after seeing it in action i love the 2ndary air feed! i wasnt sure watching the build videos but seeing into the cast riser sold me!!! love that rocket stove sir!!! wish i would have found this video before i built my very cheap and efficient version of what you made!! gonna have to go through all your duild videos and make my own! love that thing!! thank you very much for the look into the riser and the 2ndary air in action!
Hi mr Ppotty1 You are always an inspiration, and thank you very much for the knowledge you share. Last year I watched all of your videos with RSH, and decided to make the one with the cast riser. I am not so experienced in working metalls, so it is a combination with metall and refractory bricks. The riser is cast with a refractory mixture. I can not put the video link with my construction Thanks again Tasos
+TASOS Hi Tasos thanks for your comment glad i helped you to build a rocket. I found your video..... very nice, it looks to be pumping out plenty of heat. Cheers,
Gary B here from Minnesota. I have been working on my version of your current stove. I thank you for your stove videos. They have really inspired me to build my own. I have my cast riser 2 months completed. All metal parts are built and I am ready to weld. Problem is my health has stopped my project. I have my first stove to get me by. We had 24 degrees F this morning so I had my first fire of this heating season and I have to say I really like my rocket stove. I am really looking forward to getting my new smaller, cast riser stove completed as my first stove is to high of BTU (I have to open windows with it no matter how cold it is. Thanks again
+Jacque B Hi Gary, From the vids I have seen of your stove it sure is well build and should last a very long time, you put alot of thought into it and get more than enough btu's out as a result. I really liked the free flowing air tubes in the exchanger I used a similar idea in this stove as you saw. Well I hope your health improves and you get back to your next build Id love to see what you have come up with this time. Regards.
Thank you for your fine videos! I appreciate your approach to workmanship. A question: How important do you think it is to have thermal mass for heat accumulation inside the fire box in order to get the temperatures high enough for gassification? I ask because I am more apt to make a stove cast from perlite / cement which aims for high insulation. Would higher density ceramic tiles lining the inside to store heat be sensible? The same thing applies to the heat riser.
+Derek Eder Thanks Derek, Inside the firebox anything that stores a little heat would do the job, the steel alone would not stay hot so you can use solids or more lightweight, solids will take longer to heat but store it for slightly longer, lighter will heat faster but still hold the heat for the duration of the burn which is all we need really. same applies to the riser. Solids are better outside the stove to store heat when the fire stops burning, Cheers.
Question. What if you could get your hands on a cast iron riser and insulate the outside of it with a refractory material? Would it be more trouble then it's worth?
Great series of videos! You answered many of my questions. With regard to the top plate deforming from the intense heat, couldn't you use a piece of cast iron or is the cost not worth it?
Hi Tom, yes cost a big factor the plate or sawblade underneath actually fixed the problem and probably with so many cycles of extreme heat the top maybe stabilised anyway
Can you tell me why you feel the incoming air needs to be preheated and further still after your final construction? As intercoolers on a Diesel engine try to cool the air to get a greater greater burn so what is your reasoning for heating it rather than cooling it please? thanks Duncan
Hi duncan, I guess the difference is that diesel has a lower flash point than wood, and maybe colder air going into an engine has other benefits.... pre-heating the air going over the timber releases the gasses within and makes a cleaner hotter burn, also slows down the burn rate of the timber. cheers
Two questions: On a cold day, what is the outside temperature where your at? Do you have any condensation anywhere from the cold outside air intake as it warms up? Thanks for the videos, CJ
+CJs Custom Tems as low as 25f some days last winter the nights colder. there are no issues with condensation on the incoming air and really only see the chimney condensation when the fire is first lit. Cheers.
Always illuminating...pardon the pun. So if one wanted to increase the heat retention, could one place soap stone or other materials around the stove to capture heat instead of creating a huge mass to store the heat? Thanks
+1timby Hi timby, yes that would capture heat for sure but too thick a mass around the exchanger would keep some heat locked inside which would end up going out of the chimney better to keep the mass near the bottom half of the exchanger and around the flue. Cheers.
excellent view of the vortex .. I use an Inconel vaporiser tube to feed propane into my Combustion zone . the secondary heated airflow I introduced in a fanned out delivery .. a bit like squeezing the end of a garden hosepipe to create a fan effect with greater surface area .Maybe if the lower portion of the riser was made like a bowel, the secondary air mixing and burn would have more time to mix prior to leaving to go up the riser . I achieved a torroidal mixing of the burning fuel and secondary heated airflow . almost pinning the tumbling air/fuel mixture towards the initial /lower end of the combustion zone .
combustion chamber testing / refining airflow . over 20 years ago I built a test rig for my small Turbine engine . this test rig gave me a HANDS ON insight to the problems I was experiencing with Flame outs and overheating Nozzle guide vanes (NGV). and glowing yellow hot turbine wheels .Seemingly excellent burn visible in the combustion chamber dashed to pieces by the huge slick of unburnt fuel on my workshop floor . The cure for this was to fan out the ends of the vaporiser tubes (annealed Inconel) resulting in the fuel FAN having a greater surface area allowing air / oxygen to the otherwise solid stream leaving the vaporiser tubes . Moving back to the solid STREAM of FUEL ,some of it containing a mixture of unburnt content . Hence your excellent thoughts to utilise a pre heated secondary heated airflow over the fuel / wood. Introducing it too early will have the effect of creating even more gasification .( A more fuel rich burn) . I am trying to imagine a way of introducing the superheated secondary airflow entering the burn tunnel in a vortex promoting stream .. similar somehow to your brilliant offsetting vortex generator prior to the fuel entering the Riser tube . So to recap. a similar offset entry .. ( like the flow director prior to the riser ) If that simple and brilliant thinking could be adapted to the entrance to the burn tunnel / tube . then the vortex generated along the burn tube would increase the mixing and some experimenting with the riser vortex generator entry shape could accelerate the spinning airflow entering the shaped lower portion of the riser tube .. Over to you, you are the man with the skills to make it happen . . Food for thought . All you need is 48 hours in every day .
Very much enjoyed your video. I'm here in Nova Scotia, Canada. I've started construction on a Rocket Mass Heater. I very much appreciate the time you are giving to share this information. Thank you.
Brilliant. Two questions: 1. Do you think this sort of system could be adapted to create an oven with hob similar to a traditional wood stove for cooking etc. 2. Could one rocket stove, like this one you have created, be used for heating water and as a cooker, multi-use, or is that wishful thinking even for a rocket stove.
Id say yes to both questions Dan, for heating water you would need to increase the size of the firebox to increase burn time and a fairly big tank to store the hot water if you are running it through radiators. Cooking is easier as you could heat a mass around the oven to even out the temps and to store the heat to cook the food, the hotplate is the easiest part of a cooker to build with one of these. My pizza oven rocket heats the stones inside now to 400c in 15 mins on a handful of sticks. the heat generation is terrific on rockets you need to think of ways to store that heat and use it for your needs. Cheers.
Thank you. Your explanation throughout the video was very nice. I had a couple questions if you don't mind... 1. At the entry to the riser tube, do you have a plate directing the air flow to one side to force the vortex or is it a open mouth of the same dimension as the inner riser diameter? I have seen a design where a plate directs the flow to create a vortex and am wondering if its necessary. 2. The secondary air intake, is that a straight pipe? Feeding from the outside, through the outer heat chamber/fire box, into the riser tube? I ask because others that have talked about the design of rocket stoves recommend heating the secondary air intake so the cold outside air does not cool down the gasses preventing gasification. Is this in line with what you've done? 3. If you have a slight air flow from seams letting in room temp drafts going through the fuel box (you mentioned the draft between the front fuel box and the fire box/ gassification chamber) does that diminish the level of gasification? 4. Continuing from 3, If the front cover were open while you were feeding in wood does that draw of cooler air disrupt you temperature greatly if left open? Will gasification stop to the point where steam and other gasses will exit the flue? I'm working on the design and acquiring the materials needed to build my own rocket stove so any input and time your willing to lend in response to these questions is greatly appreciated in advance. Thank You
Hi yes there is a turn in the riser mouth to direct the gasses etc, you could put a wedge directly in the back of the riser without a turn which does create a double vortex but its not as efficient I have tried many ways. The sec air tube is copper and doubled over inside the riser, gets very hot which is plenty of pre heat although its not really needed as it does not effect the gassing being colder. The fire box is not completly air tight when closed off there is slight seepage which is fine as you need a little air moving over the fuel without it the fuel would starve and slowly stop burning. If you leave the door open yes the gassing will suffer as too much air enters and the fuel burns away faster. once the stove is up to temp the condensation from the flue is not seen. Good luck with the build, there are a few videos on my channel showing the various elements on this build. Cheers
Sorry to ask so many questions but this is a fascinating concept. love your videos very informative. One question though , where would i buy the glass for any doors i may make.
I made my own rocket stove yesterday. Still have a few holes to drill , but it's 99% completed. Have to do my first fire. You got a great vortex and I like that window.
Steam coming out of the flue indicates that the wood is not dry. This is why the stove is taking time to heat up properly. Much better to start off with good dry wood.
+kitemanmusic Id regard 20% moisture content as dry wood but a rocket stove will still produce condensation when burning it, the sticks i start the fire with are probably 5% moisture and still produce it, the reason is the low flue temps. stove takes a little longer to get to temp due to cast riser, however steel riser will still produce condensation even though it heats up quicker.
This is amazing, I watched many rocket stove videos for research, and your videos and stove are the best. I plan to make one for house heating (central heating). I plan to put a tube spiral with water inside heat exchanger, and one thing wonders me, how long does it burn with hardwood, that interests me for the night?
+Jovan Ilic Thanks Jovan, A copper coil inside the exchanger would work really well and produce plenty of hot water. The burn time factor is a difficult one and hard to give a definitive answer and i will explain why. When you shut the air down the wood burns slower but gradually produces less heat, so on this firebox once up to temp i could fill it and expect around 4-5 hours of heat maybe a little more with good dry hardwood. Problem is if your trying to heat water you need constant heat not declining heat so you will get a downward curve in temps..this would be the same for any stove though. To compensate you need a much bigger firebox that will give off more heat for the same time period or burn alot longer with the same downward curve. However a very large firebox can cause problems when the stove is cold. I have not fabricated this yet but I have ideas for a bigger linked firebox meaning two or three times the current size but split in half, one half is used to heat the stove the other used for the slow burn period as you would overnight. there are a few ways to achieve it just need time to work on the idea. Good luck with your build if you get it right you wont be sorry you built it. Cheers.
+ppotty1 tnx for answer, I have just around 70 square meters of house to heat, and there would not be a lot of water in the system, and for that rason water will not be cooled a lot, whole system would be covered with around 30m of copper pipes 15mm in diameter, 3 radiators, and a coil inside a stove, all around 30l of water.
+ppotty1 You're welcome. Just watched some other video's this evening and really love it ! Can appreciate good 'ol craftsmanship and expertise. You're explaining everything in a good way and very pleasant to listen to it without yelling and using music. And just subscribed your channel. To bad you are not my neighbour. Thanks !
I want to make one of these from brick and build in the garden running the exhaust through a bench. You mention secondary air but where is the primary air intake or is this just the top of the fire box?
because the firebox is large without a lid it will burn out of the top, once the riser is screaming hot and drawing well the door can be opened without any problems
Hi Jd yes just make the riser in stainless steel the exchanger can be as thin as an oil drum, firebox can be 2mm thick as long as you line the inside with insulation or refractory. The latter makes for a better burn anyway.
+ppotty1 I've tried to scale the riser and heat exchanger back. Only have a 2.75" diameter riser. Hoping to extend the burn time to keep the tent warm at night...
a bigger firebox is the answer but you will struggle with your riser I would think about piling up rocks or stones inside some mesh behind the stove and the sides to store heat. it would be released over several hours when the fire goes out.
ppotty1 brilliant look forward to it , planning to build a similar one as building a garage 28x 18 and want toastie for a change!!, was thinking about making the outer octogon shape to help flow round with added fins on outside with mabe a small fan to move air over them
+Adrianus P.M. Heersche Hi Adrianus, Yes I still have the birds I have not bothered flying them too much due to moulting, kind of sends them a bit crazy, now darker nights are here which makes flying difficult.
The bricks would act as an insulator forcing much of the heat out of the flue, it would take along time to feel the heat radiating out you can stack them round the flue to absorb the heat form it. we use steel because it conducts the heat out fast meaning less goes up the flue.
Oh,never thought about that... So steel is crucial in this build.I dont have space in my house for long flue pipes like you have ,that is my problem so i wanted to use heat from the top of the exchanger. Thank you for your time,much appreciated!
that`s right kalimerahellas that`s why stars rotate in different directions from north or south shame it disproves flat earth p.s eric dubay is a dipshit who proves NOTHING
***** All refractory cement nothing else mixed in? I want a mass and straight out chimney so I would need to insulate around riser correct? I see a Rocket stove for sale 1200$ made with all metal. They tefloned inside chambers/riser no insulation(have fins outside burn chamber) so need a upright chimney for draw. Do you think refractory cement has enough insulation for verticle mass/pump action?? Thanks 563 517 1123
***** Some add perlite or other stuff to insulate so chimney works better to pump out the flue rather than pull out the flue gas. With hotter temp inside rizer vs outside there is better push of gas and chimney does not need to be as tall.
Наука
Excellent job with the stove and the peek a boo window. I knew that the clear pot lid was going to end up on the floor. That glass is rated for maybe 600 F. You have been quite inspiring to me as I have been working on a stove very close in design as your own. I poured my core more than a month ago and I've been working on the rest of the layout of the heat exchanger. My difference is that I added wax tubes and jets for the secondary air and tertiary air and the intake for them come out the bottom of the riser. I fired the core in a makeshift kiln last week and removed the wax and string from the air ways. That way I can draw the preheated air from the air chamber below the heat exchanger. They both have their own adjustable air ways. The firebox will also have its own adjustable air way. So three separate valves to control the air flow that will be under the heat exchanger. I might have to add an experimental window to see how things flow before I finish building the top for it. When I get done, I will include pictures and videos. Thanks for the great ideas and plans.
+James Gulrich Hi James sounds really interesting what you are doing I love seeing new designs and improvements. I sort of knew the lid would die horribly only got around 5 mins out of it before it went. I have to keep saying to myself dont get involved in stoves as I have many things i want to do but its difficult when its in your blood. Cheers.
Thanks very much for sharing! Much appreciated!
+Kevin Chamberlain cheers Kevin
성 남ㅍ남성
I want to open a business with you. We have been doing this for over twenty years. There are many different interesting developments. We do not have opportunities like your country. Look at our coal-fired boilers.
According to our technology, coal burns much cleaner than gas in other boilers.
We can apply electronics to this technology, as in modern cars.
You're a real craftsman, love this video. Thanks for subscribing to my channel! Ta for now....
Great information, I really like looking inside the containment vessel down into the Vortex in the riser tube. Thank you!
thanks its hot down there for sure.
I've been waiting for this video! Stove is looking great. Thank you for taking your time and showing us.
+BSM Prod Thanks happy you enjoyed it.
I cimbali
Very nice explanation of the stove and secondary combustion too.
Glad you liked it!
I enjoyed this video quite a lot! Thanks for taking time to explain the "why" of how it all works!
+freestylebotanist thanks for that.
Excellent videos!! Have you ever considered introducing waste oil into a rocket stove? I'm wondering what it would take to accomplish that.
a tray with refractory ceramic fibre soaked in oil placed in the combustion chamber works very well
Flame, gassy burny flame in there.. Lol
love technical terms. lol
Best Rocket Stove video I have ever seen. Well done! I plan to start building one using some of your methods next spring, but I want to use water as a thermal mass, and then pump the water through radiators attached to the central heater to heat the house. I want to use an Arduino for temperature control, to turn on water pumps and fan, and to open and close the air intakes automatically. I think it will be a fun build, and hope I can post vids next year.
+MindVaccine Thanks mate, no reason why your system wont work, once you get the water up to temp it should be easy enough to maintain by the stove. I would try and make the water exchanger as big as you can by maybe fitting jackets to the inside of the rocket exchanger, I had a thought about fitting small radiators to the inside of an exchanger and linking them together with iron pipe fittings to form the jacket, I dont think they would deteriorate as the inside of the exchanger on this stove has not suffered at all. Cheers and look forward to what you come up with.
Can you please tell me if you could make two stoves into one ?? Take a wood stove and attach it to a rocket stove so that it would burn for 8 hours so one can sleep ?? Thanks
you probably could but not sure how clean it would burn
@@LozHarrop Loz, do you think you could find out somehow ??? This is not my area of expertise. Thanks also fella. One last thing, Happy New Year seven days late.
@@LozHarrop We have already done. Even rubber burns without harmful emissions. We can make various boilers from the smallest to the largest.
Well-Done
Hey boss tons of design and fabrication in action, looks fantastic and works the best I've utube , keep up the good welds, lol
Cheers
what is the mix for the refractory, and where can it be purchased
2/3 refractory 1/3 perlite I used the high temp castable refractory from castree kiln
Why not making hole in chimney tube, as neostove can,
each hole with a short tube, oriented 45° (as vortex A.V.E.C. -search french quant'homme forum ).
Also try cast iron plate, or someting like that (refractory brick)
curved (watch samourai carpenter, stone),
placed in fire chamber at basis chimney.
Dragon stove seems making vortex (concentrating heat-fire on curved plate).
-had to do a video of brick BBQ, but only just test-
Have good automn.
+fred san Thanks for the comments Fred look forward to your video. Cheers.
Hello, How is the material you use in the center, This is resistent, and I don't know it. Tahnk you so much. Anna
А планета Земля-то .... КРУТИТСЯ-ВЕРТИТСЯ!!!, - "look into the burning riser" и увидишь по факту действие силы Кориолиса.
(And Planet Earth .... cool, turns!!!, - "look into the burning riser" and see.... )
so you could be making biochar and also hot fires. using less wood and then removing charcoal after??
Awesome! :)
is there any science similarities between N of the equator toilets flush in a counter clockwise direction and below eq toilets flush in a clockwise direction......any relationship to riser vortexes? thank you! and admire your knowledge
no it does not make any difference.
d koshman that is a myth water does not i repeat does not spin in any particular direction wherever you are on earth its only the direction the water enters let`s say a toilet bowl sink tub try it in your kitchen sink
Doesn't the yellow color of the fire suggest incomplete burning?
+Mike Nestle No Mike if it was incomplete there would be plenty of smoke coming off this is a very clean burn once the stove burns off the gas this does burn with a more blue flame.
thank you Pete, is it?would u please comment......is there any relationship between cubic ft. size of fire box, regards chimney pipe flue size ?thank u so much..I super enjoy your videos and knowledge.
+d koshman No mate my name is not Pete lol ...There is no real relationship and alot depends on the type of firebox too but say your flue is 6 inch you can make your firebox 9 inch and should not be a problem dont go too high with it though and never more than half the height of the exchanger in my experience. Cheers,
Smat system.
What temperatures are developed in the riser?
When the primary air is off what causes the gas from the wood to migrate to the area of burning?
Thanks, the riser base will be around 700C-800C on a full burn, the heat from the riser pulls the gasses from the firebox you do need a small amount of primary air to keep the flow fed or the fire dies out eventually.
Remove that small kaowool trough, and build/weld in a slightly bigger trough out of 5x30x30mm angle-iron around the inside of the top of the main body of your stove, and then fill it with iron-sand. Then weld a 5x30mm flat-bar standing on edge, on the underside of your square lid, so that it will fit centrally right around the 5x30x30mm angle-iron trough, and the iron-sand will seal it, whilst still allowing it to expand and contract, independently of the main body of the stove, and this also allows for easy removal/replacement of the lid.
Thanks Paul, Nice method that to seal the top. Ive actually had no problems since I welded the plate underneath properly, and i have learned i dont need to burn the stove at crazy heats, i just burn lower temps now and the workshop is still nice and warm. Cheers
Excellent stuff. I've been hoping for while that you'd show how the cast riser is holding up. Thanks a lot.
+Marcel Lenormand Thanks Marcel.
Great set of videos progressing to this. Look at the following reference: bioenergylists.org/stovesdoc/Ogle/nordicarocket.pdf. They looked at stoves in various configurations. One of the observations was that the oxygen conversion (ie less O2 in the stack gas) was better as they lowered the pot closer to the top of the riser. The conclusion was that this reduced flow and allowed the slower burn resulted in a better burn out. This is in line with your throttling the primary and going for secondary burn of gasified wood gas. Nice job all round.
+Rex Zietsman Thanks Rex, read through some of the document less gap over the riser does slow down burn and increase temps at the top of the exchanger, while a bigger gap puts more heat into the sides of the exchanger sort of in line with their pan tests. but as they found not enough gap causes the fire to stall, causes problems with many builds as the fire then burns out of the batch box. Cheers.
I am going to build a rocket stove some day. So very good info thank
Go for it mate
outstanding stove. You used a cast riser I was wondering if a ceramic pipe would make a good riser with refacory brick fire box. just a a thought.
+Ascoolone thank you yes ceramics and fire brick are good combinations
Like the secondary air idea. I notice at the time of the filming it draws air from the shop instead of the outside. I gather because you where not finished yet. yours is the first I have seen with a completely enclosed firebox that prevents living space air from being vacuumed out the heater. Thus working counter productive. I like this design.
+Q Az Thank you, yes the intention was to have the stove feed from outside air supply preventing draughts inside and pulling warm air from inside, my intention (not done yet!) is to connect the sec air to the outer air feed on the outside of the air control damper so it can run independently. This is the reason the feed intake box was extended so far to the right to connect the sec air pipe in. Hope that makes sense. Cheers.
Very good , love the explanation....Burning my Gasifier right now...
Thanks Mate
I noticed all your connector tubes are square or rectangular, can one use a round pipe ( 6-7 in. approx. ) for the connector tube from fbox to the riser tube ?? thanks!
+d koshman Yes you can use round tube without any issues. Cheers.
I thought it was burning cleaner before the secondary air was used.
Is there any reason not to have both air intakes open?
Has anyone tried adding a preheated secondary air to the top of of the internal pipe.
so inlet 1 would burn the wood, inlet 2 would burn any unburned gases.
Taking this a step further has anyone tried having 3 burn chambers all feed with preheated air?
It probably burns TOO hot with the primary and secondary air full open/on at the same time. Obviously there has to be some primary air to burn the wood initially, when it is closed down, the primary air isn't COMPLETELY cut off. The secondary air really helps to burn off the smoke/woodgas produced in the firebox to give it a very efficient smokeless flame in the end. Get as much consumption of all fuel as possible.
Nice work. Great info. Can you share with me your mixture for your riser? I am getting ready to do a build soon
Interesting videos. In the end of the video you mention you want to weld some fins on the stove to extract heat from surface of it. Who don't use the convection principle? You could put a piece of sheet metal around the heat exchanger part and put it so it has 1 inch clearance. Then the air will start to rise between the surface of the stove and the sheet metal. It will make a circulation of air in the room and distribute the heat much better into the room.
+Jan Holst I plan to do that around the upright flue section Jan cheers.
Hi ppotty1, Very good videos. Cant wait to start building one like this. Thanks for building this.
+Harry Clark Thanks Harry, I hope you do build one and see how much heat you can produce from so little fuel and how clean they burn.
cast riser is your draw issue, not that it is a real problem for your use. if you had used a lower mass refractory with perlite, rock wool or light fire brick would help keep the heat inside. secondary air wouldn't be required.
+don ratcliff Hi Don, agreed when the riser is really cold it needs a bit more effort, but if the wind is blowing it makes no difference as the draw is really good.
i watched the videos of you making the rocket stove but not until now did i find this one!!! i love this stove and after seeing it in action i love the 2ndary air feed! i wasnt sure watching the build videos but seeing into the cast riser sold me!!! love that rocket stove sir!!! wish i would have found this video before i built my very cheap and efficient version of what you made!! gonna have to go through all your duild videos and make my own! love that thing!! thank you very much for the look into the riser and the 2ndary air in action!
+Benjamin Beardsley Tahnks Benjamin its a little furnace when it gets going.
Hi mr Ppotty1
You are always an inspiration, and thank you very much for the knowledge you share.
Last year I watched all of your videos with RSH, and decided to make the one with the cast riser. I am not so experienced in working metalls, so it is a combination with metall and refractory bricks. The riser is cast with a refractory mixture.
I can not put the video link with my construction
Thanks again Tasos
+TASOS Hi Tasos thanks for your comment glad i helped you to build a rocket. I found your video..... very nice, it looks to be pumping out plenty of heat. Cheers,
It looks like you have your own crematory. that vortex tells the tale--awesome.
Gary B here from Minnesota. I have been working on my version of your current stove. I thank you for your stove videos. They have really inspired me to build my own. I have my cast riser 2 months completed. All metal parts are built and I am ready to weld. Problem is my health has stopped my project. I have my first stove to get me by. We had 24 degrees F this morning so I had my first fire of this heating season and I have to say I really like my rocket stove. I am really looking forward to getting my new smaller, cast riser stove completed as my first stove is to high of BTU (I have to open windows with it no matter how cold it is. Thanks again
+Jacque B Hi Gary, From the vids I have seen of your stove it sure is well build and should last a very long time, you put alot of thought into it and get more than enough btu's out as a result. I really liked the free flowing air tubes in the exchanger I used a similar idea in this stove as you saw. Well I hope your health improves and you get back to your next build Id love to see what you have come up with this time. Regards.
If from usa,will the vortex circulate ,turn in the opposite direction than that from the East side of the pond ?
No idea mate but it makes no difference which way it turns.
THANKSGIVING
Thank you for your fine videos! I appreciate your approach to workmanship.
A question: How important do you think it is to have thermal mass for heat accumulation inside the fire box in order to get the temperatures high enough for gassification? I ask because I am more apt to make a stove cast from perlite / cement which aims for high insulation. Would higher density ceramic tiles lining the inside to store heat be sensible? The same thing applies to the heat riser.
+Derek Eder Thanks Derek, Inside the firebox anything that stores a little heat would do the job, the steel alone would not stay hot so you can use solids or more lightweight, solids will take longer to heat but store it for slightly longer, lighter will heat faster but still hold the heat for the duration of the burn which is all we need really. same applies to the riser. Solids are better outside the stove to store heat when the fire stops burning, Cheers.
Question. What if you could get your hands on a cast iron riser and insulate the outside of it with a refractory material? Would it be more trouble then it's worth?
Yes probably would be, you could wrap the outside in Kao wool to keep the heat inside though.
Great series of videos! You answered many of my questions. With regard to the top plate deforming from the intense heat, couldn't you use a piece of cast iron or is the cost not worth it?
Hi Tom, yes cost a big factor the plate or sawblade underneath actually fixed the problem and probably with so many cycles of extreme heat the top maybe stabilised anyway
Hi Ppotty, does this have a fan or is completely powered by natural draft?
+big10zin yes just under its own draught no fan.
Mine is similar but get my spin from a curved semi exhaust tip mounted in the cleanout door but this is defiantly better.
Thank you
Can you tell me why you feel the incoming air needs to be preheated and further still after your final construction? As intercoolers on a Diesel engine try to cool the air to get a greater greater burn so what is your reasoning for heating it rather than cooling it please? thanks Duncan
Hi duncan, I guess the difference is that diesel has a lower flash point than wood, and maybe colder air going into an engine has other benefits.... pre-heating the air going over the timber releases the gasses within and makes a cleaner hotter burn, also slows down the burn rate of the timber. cheers
Thank you for showing us what's going on in your rocket stove. That vortex is impressive.
+KindGuitar Thanks mate, it was interesting for me too.
Two questions: On a cold day, what is the outside temperature where your at?
Do you have any condensation anywhere from the cold outside air intake as it warms up? Thanks for the videos, CJ
+CJs Custom Tems as low as 25f some days last winter the nights colder. there are no issues with condensation on the incoming air and really only see the chimney condensation when the fire is first lit. Cheers.
Always illuminating...pardon the pun.
So if one wanted to increase the heat retention, could one place soap stone or other materials around the stove to capture heat instead of creating a huge mass to store the heat?
Thanks
+1timby Hi timby, yes that would capture heat for sure but too thick a mass around the exchanger would keep some heat locked inside which would end up going out of the chimney better to keep the mass near the bottom half of the exchanger and around the flue. Cheers.
***** Hmm so one could add soapstone or some other mass around the bottom part. Can you cook on the top if needed?
Thanks
+1timby yes more that enough heat to cook on the top, you could fabricate an oven that would work well on the top.
Thanks!
See
Very good!
+kbbacon thanks as always Kev.
Marvelous, ramble as much as you want. I'm taking it all in.
+ROBERT AITKEN Thanks Robert I generally remove 2 hours of rambling from each video lol..
excellent view of the vortex .. I use an Inconel vaporiser tube to feed propane into my Combustion zone . the secondary heated airflow I introduced in a fanned out delivery .. a bit like squeezing the end of a garden hosepipe to create a fan effect with greater surface area .Maybe if the lower portion of the riser was made like a bowel, the secondary air mixing and burn would have more time to mix prior to leaving to go up the riser . I achieved a torroidal mixing of the burning fuel and secondary heated airflow . almost pinning the tumbling air/fuel mixture towards the initial /lower end of the combustion zone .
Interesting idea Richard. cheers
combustion chamber testing / refining airflow . over 20 years ago I built a test rig for my small Turbine engine . this test rig gave me a HANDS ON insight to the problems I was experiencing with Flame outs and overheating Nozzle guide vanes (NGV). and glowing yellow hot turbine wheels .Seemingly excellent burn visible in the combustion chamber dashed to pieces by the huge slick of unburnt fuel on my workshop floor . The cure for this was to fan out the ends of the vaporiser tubes (annealed Inconel) resulting in the fuel FAN having a greater surface area allowing air / oxygen to the otherwise solid stream leaving the vaporiser tubes . Moving back to the solid STREAM of FUEL ,some of it containing a mixture of unburnt content . Hence your excellent thoughts to utilise a pre heated secondary heated airflow over the fuel / wood. Introducing it too early will have the effect of creating even more gasification .( A more fuel rich burn) . I am trying to imagine a way of introducing the superheated secondary airflow entering the burn tunnel in a vortex promoting stream .. similar somehow to your brilliant offsetting vortex generator prior to the fuel entering the Riser tube . So to recap. a similar offset entry .. ( like the flow director prior to the riser ) If that simple and brilliant thinking could be adapted to the entrance to the burn tunnel / tube . then the vortex generated along the burn tube would increase the mixing and some experimenting with the riser vortex generator entry shape could accelerate the spinning airflow entering the shaped lower portion of the riser tube .. Over to you, you are the man with the skills to make it happen . . Food for thought . All you need is 48 hours in every day .
Thanks very much for taking the time and going to the trouble of creating and sharing this video. Extremely insightful, as always.
+Vince Busch Thanks Vince,
Very much enjoyed your video. I'm here in Nova Scotia, Canada. I've started construction on a Rocket Mass Heater. I very much appreciate the time you are giving to share this information. Thank you.
+Mike Porter Cheers Mike, you will wonder why you never built one sooner.
ppotty1
Brilliant. Two questions:
1. Do you think this sort of system could be adapted to create an oven with hob similar to a traditional wood stove for cooking etc.
2. Could one rocket stove, like this one you have created, be used for heating water and as a cooker, multi-use, or is that wishful thinking even for a rocket stove.
Id say yes to both questions Dan, for heating water you would need to increase the size of the firebox to increase burn time and a fairly big tank to store the hot water if you are running it through radiators. Cooking is easier as you could heat a mass around the oven to even out the temps and to store the heat to cook the food, the hotplate is the easiest part of a cooker to build with one of these. My pizza oven rocket heats the stones inside now to 400c in 15 mins on a handful of sticks. the heat generation is terrific on rockets you need to think of ways to store that heat and use it for your needs. Cheers.
Much appreciated, Cheers.
Thank you. Your explanation throughout the video was very nice. I had a couple questions if you don't mind...
1. At the entry to the riser tube, do you have a plate directing the air flow to one side to force the vortex or is it a open mouth of the same dimension as the inner riser diameter? I have seen a design where a plate directs the flow to create a vortex and am wondering if its necessary.
2. The secondary air intake, is that a straight pipe? Feeding from the outside, through the outer heat chamber/fire box, into the riser tube? I ask because others that have talked about the design of rocket stoves recommend heating the secondary air intake so the cold outside air does not cool down the gasses preventing gasification. Is this in line with what you've done?
3. If you have a slight air flow from seams letting in room temp drafts going through the fuel box (you mentioned the draft between the front fuel box and the fire box/ gassification chamber) does that diminish the level of gasification?
4. Continuing from 3, If the front cover were open while you were feeding in wood does that draw of cooler air disrupt you temperature greatly if left open? Will gasification stop to the point where steam and other gasses will exit the flue?
I'm working on the design and acquiring the materials needed to build my own rocket stove so any input and time your willing to lend in response to these questions is greatly appreciated in advance.
Thank You
Hi yes there is a turn in the riser mouth to direct the gasses etc, you could put a wedge directly in the back of the riser without a turn which does create a double vortex but its not as efficient I have tried many ways.
The sec air tube is copper and doubled over inside the riser, gets very hot which is plenty of pre heat although its not really needed as it does not effect the gassing being colder.
The fire box is not completly air tight when closed off there is slight seepage which is fine as you need a little air moving over the fuel without it the fuel would starve and slowly stop burning.
If you leave the door open yes the gassing will suffer as too much air enters and the fuel burns away faster. once the stove is up to temp the condensation from the flue is not seen.
Good luck with the build, there are a few videos on my channel showing the various elements on this build. Cheers
having two channels confuses the hell out of you tube lol
Sorry to ask so many questions but this is a fascinating concept. love your videos very informative. One question though , where would i buy the glass for any doors i may make.
you can get it cut on ebay or online suppliers ceramic glass for wood stoves
all glass has failed me. Ceramic is all that is left to try.
Great job.
Thank you! Cheers!
The secondary air pipe . How do you put that in?
I made my own rocket stove yesterday. Still have a few holes to drill , but it's 99% completed. Have to do my first fire. You got a great vortex and I like that window.
+Tim Spriggs you should get a video up Tim be good to see it.
If I can figure out how to combine the separate lil' videos I made, in Linux. thank you tho.
Hi, I'm gonna make something like this, do you think it's ok to use a cement mixer to make the refraction mix ??
Atb Lee
+fleabag72 Yea that would be fine Lee put all the dry stuff in first so it mixes properly.
+ppotty1 cheers mate
Hi thanks for the reply but I am really a novice here. When you say refractory what is that, cement?
Its a high temp mixture that fire bricks are made of...link here for the 1400c stuff. www.castreekilns.co.uk/insulating-castable-191-c.asp
Steam coming out of the flue indicates that the wood is not dry. This is why the stove is taking time to heat up properly. Much better to start off with good dry wood.
+kitemanmusic Id regard 20% moisture content as dry wood but a rocket stove will still produce condensation when burning it, the sticks i start the fire with are probably 5% moisture and still produce it, the reason is the low flue temps.
stove takes a little longer to get to temp due to cast riser, however steel riser will still produce condensation even though it heats up quicker.
+ppotty1 Thanks for your reply. I have a regular woodburning stove which does not give out much heat with damp wood.
the riser what is is it made from did you purchase it or make it?
p.s felt warmer just watching nice work
Hi I cast it from refractory mixture, thanks
AMAZING! Thanks for sharing and taking the time to teach us others :)
Cheers, no problem
This is amazing, I watched many rocket stove videos for research, and your videos and stove are the best. I plan to make one for house heating (central heating). I plan to put a tube spiral with water inside heat exchanger, and one thing wonders me, how long does it burn with hardwood, that interests me for the night?
+Jovan Ilic Thanks Jovan, A copper coil inside the exchanger would work really well and produce plenty of hot water. The burn time factor is a difficult one and hard to give a definitive answer and i will explain why.
When you shut the air down the wood burns slower but gradually produces less heat, so on this firebox once up to temp i could fill it and expect around 4-5 hours of heat maybe a little more with good dry hardwood.
Problem is if your trying to heat water you need constant heat not declining heat so you will get a downward curve in temps..this would be the same for any stove though.
To compensate you need a much bigger firebox that will give off more heat for the same time period or burn alot longer with the same downward curve. However a very large firebox can cause problems when the stove is cold.
I have not fabricated this yet but I have ideas for a bigger linked firebox meaning two or three times the current size but split in half, one half is used to heat the stove the other used for the slow burn period as you would overnight. there are a few ways to achieve it just need time to work on the idea. Good luck with your build if you get it right you wont be sorry you built it. Cheers.
+ppotty1 tnx for answer, I have just around 70 square meters of house to heat, and there would not be a lot of water in the system, and for that rason water will not be cooled a lot, whole system would be covered with around 30m of copper pipes 15mm in diameter, 3 radiators, and a coil inside a stove, all around 30l of water.
Rocket stove genius. Did you do any of the voices for Thomas the Tank Engine?
+Peter Beyer Think that was Ringo star mate.
What is the distance between your riser and the saw blade?
roughly 3 inch mate
Never happens that much that i watch whole 30 min of a youtube video. Good job ! Could watch this whole evening.
+GlennnD Thanks Glen glad you enjoyed it.
+ppotty1 You're welcome. Just watched some other video's this evening and really love it ! Can appreciate good 'ol craftsmanship and expertise. You're explaining everything in a good way and very pleasant to listen to it without yelling and using music. And just subscribed your channel. To bad you are not my neighbour. Thanks !
when are you going to upload a pigeon update?
Great to see the riser has held up so well. Did you make the rocketstove boiler after the prototype?
+Robert Seal thanks robert no movement on that as yet.
sweet gave me sum ideas
Thanks
I want to make one of these from brick and build in the garden running the exhaust through a bench. You mention secondary air but where is the primary air intake or is this just the top of the fire box?
One of the vids shows the primary air path, it enters under the door on each side.
Is that the door on top of the box where you put the wood. I see many builds with the wood burner box open. Is there a reason you have yours covered?
because the firebox is large without a lid it will burn out of the top, once the riser is screaming hot and drawing well the door can be opened without any problems
I'm trying to build this stove in a lightweight hunting stove. Any suggestions where to lighten it up. Only needs to burn a couple weeks a year.
Hi Jd yes just make the riser in stainless steel the exchanger can be as thin as an oil drum, firebox can be 2mm thick as long as you line the inside with insulation or refractory. The latter makes for a better burn anyway.
+ppotty1 I've tried to scale the riser and heat exchanger back. Only have a 2.75" diameter riser. Hoping to extend the burn time to keep the tent warm at night...
a bigger firebox is the answer but you will struggle with your riser I would think about piling up rocks or stones inside some mesh behind the stove and the sides to store heat. it would be released over several hours when the fire goes out.
+ppotty1 so you think a 4" riser is the minimum?
you can go smaller than 4 but i found its not as efficient larger risers suit a vortex which make a difference you can burn a vortex in 4 inch.
Very interesting and nicely made video. Thank you.
+effyleven Thanks
terrible fire
another great video! thanks for sharing your experience and information!
+scott jenkins Cheers Scott
Do you have any plans you can share
There is a couple of videos on my channel showing the complete build.
hi,
good!
any update on this stove?
Still performing as good as when it was built mate, i might do an update on it as it will be 3 years since it was built
Do you see any deterioration in the cast?
thanks for video. nice job!
Thank you.
great job and explanations. what a beast!
+Stuart McDonnell Thanks Stuart it is mate doing some work on the flue system this year to improve things.
great understanding of what is needed .
thank you.
Any more updates on the heater , great job
Hi Andrew, Thanks yes i keep meaning to do an update on it, will try and get one done this next week. Cheers.
ppotty1 brilliant look forward to it , planning to build a similar one as building a garage 28x 18 and want toastie for a change!!, was thinking about making the outer octogon shape to help flow round with added fins on outside with mabe a small fan to move air over them
Hi , any luck with update
Just waiting for some new stove glass Andrew to finish off the video, will post it up this week mate.
How did you make the raiser?
It was cast from refractory cement mix
Loz, you still have roller pigeons? ;) ;)
+Adrianus P.M. Heersche Hi Adrianus, Yes I still have the birds I have not bothered flying them too much due to moulting, kind of sends them a bit crazy, now darker nights are here which makes flying difficult.
Yes Loz, over here we have the same problems although at least we have 1.5 hours more daytime than in the UK
Amazing work man!!One question,what about fire bricks or clay bricks for building heat exchanger and firebox?
heat exchanger should be steel so it will release the heat faster but the firebox would be good in fire brick even the riser. Cheers
Clay bricks could work for heat exchanger because they conduct and accumulate heat and fire bricks for the rest.Or am i wrong again :)
The bricks would act as an insulator forcing much of the heat out of the flue, it would take along time to feel the heat radiating out you can stack them round the flue to absorb the heat form it. we use steel because it conducts the heat out fast meaning less goes up the flue.
Oh,never thought about that... So steel is crucial in this build.I dont have space in my house for long flue pipes like you have ,that is my problem so i wanted to use heat from the top of the exchanger. Thank you for your time,much appreciated!
In a house you want to build a rocket MASS heater.
Very nice mate
+Jason Bentley thanks Jason
GR8 vid, thanks.
+nFlames2 Cheers.
man I see the sun down there at 28:40
It is possible the real sun to work that way.
+kalimeraHellas Maybe so it is a ball of burning gas after all.
*****
We don't know that! We know that the earth is flat like eric dubay proves. Lets stay on facts because everything from the nasa is a bold lie.
that`s right kalimerahellas that`s why stars rotate in different directions from north or south shame it disproves flat earth
p.s eric dubay is a dipshit who proves NOTHING
stfu you paid nsa jewish troll.
Good to see the rocket stove is back :)
+Stephen Owens yea getting some sheet steel in the morning to finally finish it all off. Cheers.
could you cook on this?
yes easily it boils water very fast when up to temp
Is that 2500 or 3000 degree refractory in rizer?
+putheflamesou 1600 C around 2900f
***** All refractory cement nothing else mixed in? I want a mass and straight out chimney so I would need to insulate around riser correct? I see a Rocket stove for sale 1200$ made with all metal. They tefloned inside chambers/riser no insulation(have fins outside burn chamber) so need a upright chimney for draw. Do you think refractory cement has enough insulation for verticle mass/pump action?? Thanks 563 517 1123
Im not sure what you mean mate, but the refractory I used was pre-mixed like a concrete with the grog added so only needed water. Cheers.
***** Some add perlite or other stuff to insulate so chimney works better to pump out the flue rather than pull out the flue gas. With hotter temp inside rizer vs outside there is better push of gas and chimney does not need to be as tall.
Awesome vortex!!!!
+John Holmes cheers John.