Green machine and 4 inch tube? Help!

[satamax]

Hi everybody.

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!



Thanks.

Max.

[Donkey]

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.

[peterberg]

Sept 2, 2013 12:50:46 GMT -8 satamax said:

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.

[satamax]

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.

Thanks again.

Max.

[satamax]

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.

[satamax]

So, huge progress has been made, pics and videos are to follow in about an hour, time to eat and upload

Attachments:

[satamax]

Not smoking much at startup hey?

I'm realy thinking about doing the V out of insulating firebrick too! When the thing got hot, what a growl!

Attachments:

[satamax]

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.

[satamax]

Soooo, rockety enough?

[satamax]

Sorry, i don't know how to rotate thoses videos on youtube or my computer. And my mobile phone is crap at capturing the sound.

[matthewwalker]

Looking good Max!

[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.

[satamax]

All lined up with insulating firebricks. I made some videos, but bad quality.

[matthewwalker]

Well Max, that's what we've been saying all along Mate! Insulate man! Seriously though, nice work. It's amazing what a difference an insulated firebox makes.

[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!