I'm studying the feasibility of fitting the green machine into my workshop.
The only prob, it's a 6 incher. but through the wall, i have only a 4 inch ish hole , 111mm exactly. The wall is about 60cm thick and the pipe running through the wall makes a slight elbow. The chimney above that hole is 14cmx20cm so that's a smidge less than 8 inch csa. Inside the workshop, i can do pretty much what i want. I tried like this, ans obviously the draft was weak and it was smoking a smidge. Or may be steaming. I havent' been up a lader to check. I did open the top of the stove, to check, it didn't seem to smoke through the 3/4 inch hole. But what do i know.
The question is, could i run this thing with 6 inch pipe all the way to the wall, then get through the restriction and then up the chimney, and it still would work all right? There would be a vertical 2 barrel bell next to the stove, then about one metre or so up after the bell, about 7 metres horizontal run. Then the restriction, and the 6 metres high brick chimney. The thing is, it would cost a fair bit to buy the pipe, so, it's better to check before what others think!
Last Edit: Nov 3, 2013 9:11:50 GMT -8 by peterberg
Umm. My impression is, that stove arrangement doesn't loose enough heat to trust that the exhaust will fit through a 4 inch opening reliably. Maybe, just maybe, if you lead it through a second metal bell or a masonry one and REALLY cool off the exhaust, it may have shrunk enough to work. It's a big gamble and may not work properly at all, under any condition.
The chimney above that hole is 14cmx20cm so that's a smidge less than 8 inch csa.
Max, I don't think that's correct. That rectangle stack won't carry the same gas velocity/volume as one of 8". The formula is this: 2 x width x depth of the chimney channel, divided by (width + depth) = 16.47 cm (6.48") diameter of a comparable round channel.
There's a very, very slim chance it would work without that 7 m (23') horizontal run. But even then, the restriction is not straight up and short but there's a sort of elbow inside. That brick chimney could be good enough, but you have to break through the chimney wall or open up the existing hole wide enough in order to get the draft you need.
Thanks a lot guys. Whatever i do to heat up that workshop to normal temps in the winter is doomed, as it seems.
Nother option, buy somme flex pipe used to line the chimneys, and go through the window. But the pipe wouldn't go up much on the outside, and go through 4' of snow in the winter, or more! May be i could have a shorter run too. But it would be hard to fit the double bell thing. Mind you, the stove on the workshop side and the bell in the other room, which i usualy don't heat could be done too. Or the previous place i was thinking, and use insulated tube for the horizontal 7 metres. Well, DIY insulated tube ! Rockwool around normal pipe.
So, i tried to increase the lengh with proper tubing and to make the transition smoother.
I also filled a gap on the external part of the chimney. It's definately drafting a smidge better. But not enough. Fire goes through the port, and is sometimes good enough. But at some other times, the fire is lazy.
I went to an old company i worked for, which has closed down, and recuperated about twenty insulating firebricks. And i will try to reduce the width of the firebox with thoses. I might put two pieces of metal to protect them.
A daft question, i could go through the window, and reach the bottom of the outside chimney, which i have closed down. This would be the proper size tubing. and chimney. But the tube, in the winted would be on the ground, and under the snow. Would that impair the draft too much? I would have about 2m of vertical going out of the stove, then about 8 ish metres horizontal, then another five vertical, in form of a brick chimney. And the good thing is, i would have the stove just next to the workbench Which should be nice.
The plan is to add a double barrel bell just after. Same as Peter's. workshop stove. And try to fit it in my workshop! And devise a P chanel!
Peter, please, if you see this, If i made a bent piece of thick steel, which would be the ceiling of the firebox, and the end of it, down to the required depth below the port, with a lip bent so it touches the end of the firebox, and the proper size cut into that lip to make the P chanel port? I'll draw it later.
Last Edit: Sept 12, 2013 11:46:32 GMT -8 by satamax
I tried the ofcuts from the insulating bricks as the ramps on each side.
Whoah, what a change. It started pulsating straight away. I'm definately converted to insulating firebricks for the batch box!
I just can't explain how chuffed i am.
This thing is a monster. Tomorow i will cut a proper ramp out of some arch (you know the ones which are narower on one side) insulating firebricks , which i can't use elsewhere. And try to capture the sound properly. It seems that my phone just cancels the sound, as if it was the wind.
I want to shout to the world, and convert everybody! Try this one with thoses insulating firebricks. It's a noots machine. Peter, you were also right about my firebox being too wide. Obviously. Have you tried any of thoses in your prototyping stages? If not, please do. Please!
Huh, btw, i still have the narrowing with 1m of 111mm tube and the elbow through the wall. It doesn't seem to affect the thing a smidge now. And i've bought more than ten metres of double wall stainless bendable pipe from my usual supplier of construction materials. I might even be talking gibberish. There might be more than ten. All that for 30 euros. It's all unsellable offcuts. Most being around the 2 to 3 metres mark. So the thingy might move soon.
Last Edit: Sept 14, 2013 14:01:38 GMT -8 by satamax
Well, this one is insulated with 5cm of rockwool on the exhaust side, and ten on all the other sides, but it was taking time to kick. While, with the insulating firebricks, it kicks instantly. On a whim, i should say!
dan1941300: If possible in metric cm, how many Celsius at the chimney? Is there anything you would do different if building again? Sorry for my bad english, my language is german, austrian. thx a lot
May 11, 2018 9:38:02 GMT -8
smarty: Dan my batchbox reached 1150C so refractory cement rated to at least 1200C
May 21, 2018 22:53:56 GMT -8
mercedes: Not sure where this question will end up...I just registered. HOW THICK SHOULD PERLITE/VERMICULATE/CLAY INSULATION BE BEHIND THE THERMAL BATTERY/COB BENCH IF IT BACKS UP TO A STRAW BALE WALL? Thanks! Can you please also post me: firstname.lastname@example.org thnx!!
May 28, 2018 20:05:23 GMT -8
kkp: Mercedes: Benches don't get real hot. In fact, they are rather cool compared to other areas. You shouldn't need a mix like you described
Jun 7, 2018 18:10:52 GMT -8
maartenmartens: beste Peter, ik heb je eergisteren een mail gestuurd via het contact formulier op je website , heb je die goed ontvangen ? mvg Maarten Martens, architect - geobioloog (mail betreffende de bouw van onze eigen RMH)
Jun 20, 2018 13:21:57 GMT -8
martinm: any one here with info \ experience with heat (from a mass heater) distribution with ducts throughout two storey house ?
Sept 8, 2018 22:58:52 GMT -8
padica: Good morning, this is a wonderful subject, please someone can help me with the theme of double and triple combustion, how it is achieved, theory and design, thank you
Sept 15, 2018 7:13:40 GMT -8
wiscojames: I'm afraid you won't get a response to such a vague question - I suggest reading through some of the threads related to your questions before asking for an explanation. People will be very generous with their knowledge if your question is more specific.
Sept 18, 2018 4:48:00 GMT -8
daniel: in my experience as I am working now on something of that nature, I have thought of making a heat exchanger and distributing the heat through vents using a slower fan. Now after a few years I realize that mass heaters give out primarily radiant heat, for
Nov 30, 2018 12:48:38 GMT -8
coastalrocketeer: Anyone posting in this shout box... if you have something you want people to see and respond to, create a thread in the appropriate forum section... this is not the place...
Dec 16, 2018 18:10:49 GMT -8
vesuvius: High Temperature Glass options,
Jan 4, 2019 16:28:17 GMT -8
vesuvius: Do any of you have experience with using the glass from home oven doors on a rocket stove? I'd like to have a viewing port on my stove but don't want to fork out for new ceramic glass. Any thought as to whether it would take the heat of a rocket stove?
Jan 4, 2019 16:30:40 GMT -8
yaya: you dont need the blowair for that temp..
Jan 13, 2019 16:43:57 GMT -8
flybywire: Glass window from an old washing machine is designed to take high temps. Cheap solution to your need.
Jan 27, 2019 0:10:58 GMT -8
coastalrocketeer: Anyone posting in this shout box... if you have something you want people to see and respond to, create a thread in the appropriate forum section... this is not the place to have a discussion... it is for short announcements
Feb 7, 2019 0:11:23 GMT -8
coastalrocketeer: you won’t likely get replies to questions here, and it is not a spot that makes holding an ongoing discussion possible...
Feb 7, 2019 0:12:22 GMT -8