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Jamie Corne
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Well - we've drempt of the engineering behind our rocket baby...but we've never actually manifested it....until tonight. In South Dakota - the ingredients were hard to come by during the winter season...but we did it.

And here's what we've done so far.


Getting the stuff mixed and ready - and trying to keep small hands "out" of it LOL



Building the beginnings of the feed chamber:



Building the fire chamber:



Final Product....for tonight, anyway:




Any input would be appreciated. We're using the following:

Fire Clay mixed with hay (for reinforcement purposes) since we really don't have access to anything else that is within our budget currently.
Vermiculite
Fire Bricks (rated for 3000 degrees F)
Porcelain Tile (for the bottom of the fire chamber and to reinforce the fuel feed for the twigs and to help against deterioration)
Sand - all purpose and gritty

We ran a few "test" clumps of the fireclay mixed with the hay inside of our wood stove and got the wood stove as hot as it's going to get to see what it would do - and it withstood the heat - and nicely. We've found that putting the powdered fire clay on the outside of the finished product above..helped it to become "stronger" and "sturdier" as the pottery folk (43 years experience) had told us it would.

We are wanting to insulate the fire chamber really well so that we can get it pretty hot since it's going to be heating 4 average sized rooms (the rooms are open with open archways) - with the stove in the middle of them - kind of like a cross with the stove being in the quasi-center.

 
Chris Burge
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Jamie,

I commend you for your perseverance and frugality, but I have to stop you before you go any further and point out a few things:

First of all, from your photos, it looks like you're using an awful lot of rather heavy clay slip to put the fire core together. During the first few burns, most of what is covering the inside of the burn chamber is going to spall (peel off). An easier method to stick the bricks together, and use less clay, is to mix up a bucket of thin slip (just barely pour-able; like keifer or smoothie), and then just dip each brick in the slip and set in place. This helps ensure the thinnest possible joint between the bricks and will give you the best longevity. Plus, it's much easier to keep the surface of the bricks smooth and ready to accept the next course-- even if you have to leave the project overnight.

Second, and this is very important, porcelain tile will not only be unable to handle the heat, it will practically explode. I merely placed one over the feed tube of a 4" system, to use as draft control, and after about 30 min...POP! It shattered into 6 pieces and flew all over the fireplace. Also, porcelain tile is not a very good insulator. If the bottom of your core is only made up of tile (and is sitting directly on a plastic tarp? or about 1" of fireclay/straw cob?) then I strongly recommend (if not desperately request), that you start over while you still can. At this point, if you continued your build and actually lit a fire in there, the entire bottom will shatter and begin burning the plastic long before it eventually shattered the three walls of your feed tube. Even if you had a bottom course of firebrick instead of tile, it would still get plenty hot on the underside and wind up melting the plastic and releasing all kinds of nasty fumes and toxins into your home. You would do better if you simply built directly on top of the plywood, but only if you lay down a full course of brick for the bottom of your system before laying the first course of firebrick for the bottom of your feed tube/burn tunnel/riser.

I know... after committing to a task and making progress towards a goal, the last thing you want to hear is, "start over", but I not only want you to succeed, I also want you to avoid a potentially dangerous situation. Hopefully you haven't gotten any farther than your last photo and you won't be looking at that big of a reset.

Good luck, keep at it, and keep posting pics!

Chris
 
Jamie Corne
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Chris Burge wrote:Jamie,

I commend you for your perseverance and frugality, but I have to stop you before you go any further and point out a few things:

First of all, from your photos, it looks like you're using an awful lot of rather heavy clay slip to put the fire core together. During the first few burns, most of what is covering the inside of the burn chamber is going to spall (peel off). An easier method to stick the bricks together, and use less clay, is to mix up a bucket of thin slip (just barely pour-able; like keifer or smoothie), and then just dip each brick in the slip and set in place. This helps ensure the thinnest possible joint between the bricks and will give you the best longevity. Plus, it's much easier to keep the surface of the bricks smooth and ready to accept the next course-- even if you have to leave the project overnight.

Second, and this is very important, porcelain tile will not only be unable to handle the heat, it will practically explode. I merely placed one over the feed tube of a 4" system, to use as draft control, and after about 30 min...POP! It shattered into 6 pieces and flew all over the fireplace. Also, porcelain tile is not a very good insulator. If the bottom of your core is only made up of tile (and is sitting directly on a plastic tarp? or about 1" of fireclay/straw cob?) then I strongly recommend (if not desperately request), that you start over while you still can. At this point, if you continued your build and actually lit a fire in there, the entire bottom will shatter and begin burning the plastic long before it eventually shattered the three walls of your feed tube. Even if you had a bottom course of firebrick instead of tile, it would still get plenty hot on the underside and wind up melting the plastic and releasing all kinds of nasty fumes and toxins into your home. You would do better if you simply built directly on top of the plywood, but only if you lay down a full course of brick for the bottom of your system before laying the first course of firebrick for the bottom of your feed tube/burn tunnel/riser.

I know... after committing to a task and making progress towards a goal, the last thing you want to hear is, "start over", but I not only want you to succeed, I also want you to avoid a potentially dangerous situation. Hopefully you haven't gotten any farther than your last photo and you won't be looking at that big of a reset.

Good luck, keep at it, and keep posting pics!

Chris


Hey Chris,

Thanks for the input Greatly appreciated.

The plastic won't be staying. I had forgotten to mention that the tiles that are on the bottom of the burn chamber - aren't porclain. They are fire tiles and under those are hardy backer. The porcelain tiles are only lining the feed tube. The very bottom of the entire thing will be brick. What we planned on doing, is taking the entire thing (off of the plastic) and outside - covering it in fallen twigs and branches - and lighting it in order to "fire" the clay.

The entire burn chamber is made of those 3000 degree bricks - sides and top.

We haven't gotten any further as of today because I was going to run into Lowes and grab some more fire tile. We will have to reset as you said then - and I'll purchase some more brick instead.

The brick for the fire chamber - does it have to be 3000 degree F brick...or can it just be clay bricks (pavers) from Lowes? I have some 3000 degree Fire bricks left...so we could line the chamber with them...and they are only available an hour away from us in Sioux Falls (we live near Brookings - one hour north of Sioux Falls).

Getting that quasi-clay wet...will it be reusable?
 
Chris Burge
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Klinker brick will hold up for a little while, and then fracture right in half.
Common red clay brick will fracture and break down.
Most 'off-the-shelf' pavers are actually cast concrete, rather than a kiln fired-brick, and will shatter the first time you fire them.

Usually, but not always, you can get unfired clay to go back into solution, but it may take a while. Most well-established potters have a 'slip vat', (which is just a bucket or tank of water and clay) of some kind where they throw rejects and scrap pieces of clay... worth a try.
 
Jamie Corne
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Chris Burge wrote:Klinker brick will hold up for a little while, and then fracture right in half.
Common red clay brick will fracture and break down.
Most 'off-the-shelf' pavers are actually cast concrete, rather than a kiln fired-brick, and will shatter the first time you fire them.

Usually, but not always, you can get unfired clay to go back into solution, but it may take a while. Most well-established potters have a 'slip vat', (which is just a bucket or tank of water and clay) of some kind where they throw rejects and scrap pieces of clay... worth a try.


Ok so I went to lowes and bought outdoor fire pit clay bricks - and met someone who had made their own rocket stove! woooo hoooo!!

Anyway - what I found out is that if we use the 3000 degree fire bricks for the entire fire chamber using the method you suggested with the slip...and then everything else with these fire pit bricks...it should last. We'll then mix the Vermiculite and other organics together for the "cob" that goes around the outside of the entire thing.

What say you? Think that would work? So you can see kinda what we're doing:



 
Jamie Corne
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I was wondering about something.

I've seen a lot of rocket heaters and mass thermal heaters where the "barrel" is exposed - and quite ugly. Then I've seen ones like in the picture below.

Does covering the barrel like that reduce the heat output?

 
K Nelfson
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Chris Burge wrote:Klinker brick will hold up for a little while, and then fracture right in half.
Common red clay brick will fracture and break down.
Most 'off-the-shelf' pavers are actually cast concrete, rather than a kiln fired-brick, and will shatter the first time you fire them.

Usually, but not always, you can get unfired clay to go back into solution, but it may take a while. Most well-established potters have a 'slip vat', (which is just a bucket or tank of water and clay) of some kind where they throw rejects and scrap pieces of clay... worth a try.


I built a pizza oven a while back and got a lot of advice that I should use firebrick. And it's good advice but the result is expensive. If you need top quality, fine, use firebrick everywhere. If you're on a budget, use firebrick where the coals sit. But for sure avoid those concrete pavers.
 
Matt Carkhuff
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from what I have read; covering the barrel does reduce the heat ouput (at least immediate heat) and can make the top hotter. I also have seen instants of videos where they claimed the drafting was reduced (looking for the video now) and that it was less "rockety".

my thought is that with young ones it may be a good idea; just leave some of it exposed like the top 14" or so. I am still gathering parts to build my first RMH so don't take my words as gold yet...
 
Jeremiah wales
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Jamie Corne wrote:I was wondering about something.

I've seen a lot of rocket heaters and mass thermal heaters where the "barrel" is exposed - and quite ugly. Then I've seen ones like in the picture below.

Does covering the barrel like that reduce the heat output?



I have also seen some people who have not used barrels, But they had a dome top on it instead of flat. I believe they used the end of a large Propane Tank instead of barrel. It looked a bit more custom. Wonder if it works the same being a dome instead of flat top?
 
Jamie Corne
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K Nelfson wrote:
Chris Burge wrote:Klinker brick will hold up for a little while, and then fracture right in half.
Common red clay brick will fracture and break down.
Most 'off-the-shelf' pavers are actually cast concrete, rather than a kiln fired-brick, and will shatter the first time you fire them.

Usually, but not always, you can get unfired clay to go back into solution, but it may take a while. Most well-established potters have a 'slip vat', (which is just a bucket or tank of water and clay) of some kind where they throw rejects and scrap pieces of clay... worth a try.


I built a pizza oven a while back and got a lot of advice that I should use firebrick. And it's good advice but the result is expensive. If you need top quality, fine, use firebrick everywhere. If you're on a budget, use firebrick where the coals sit. But for sure avoid those concrete pavers.


The firebrick that we could get is 2.19 a brick an hour from where we live. We got lucky and went to a Habitat Restore in Sioux Falls - and got 16 firebricks for .50 cents a piece...which was really nice. We lucked out - but I'm not sure that it will be enough. We'll see. We might have to make a trip back to Sioux Falls and buy the 2.19 bricks on the next paycheck. We are by no means rich...and after doing the math....it would put a huge damper on our progress - but probably worth it. Thanks so much for the post, Nelfson. Means a lot.
 
Jamie Corne
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Matt Carkhuff wrote:from what I have read; covering the barrel does reduce the heat ouput (at least immediate heat) and can make the top hotter. I also have seen instants of videos where they claimed the drafting was reduced (looking for the video now) and that it was less "rockety".

my thought is that with young ones it may be a good idea; just leave some of it exposed like the top 14" or so. I am still gathering parts to build my first RMH so don't take my words as gold yet...


We were thinking about the kids a lot - since one of them will be only 4 in April. She loves to climb too...just our luck.

I will have to check some videos out. It's hard to find videos that go into detail on these things as I don't need so much "opinion" as I do fact...since it's our family we're dealing with here. Thank you so much for the response though - a lot of useful information and much appreciated!
 
Jamie Corne
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Jeremiah wales wrote:
Jamie Corne wrote:I was wondering about something.

I've seen a lot of rocket heaters and mass thermal heaters where the "barrel" is exposed - and quite ugly. Then I've seen ones like in the picture below.

Does covering the barrel like that reduce the heat output?



I have also seen some people who have not used barrels, But they had a dome top on it instead of flat. I believe they used the end of a large Propane Tank instead of barrel. It looked a bit more custom. Wonder if it works the same being a dome instead of flat top?


Oddly enough - my mother just had my uncle bring her pressure tank (it's huge - 6 foot tall) up from the basement as the bottom rotted out - and he cut it with a torch to get it out - it's red/maroon and would probably make for one heck of container that would replace the barrel. It does have a domed top...

I wonder.......hm.....

Darnit lol you guys just put so much ideas into this skull of mine - my husband is going to hate y'all! lol. j/k

Thank you so much for your thoughts This is going to be such a fun adventure
 
Satamax Antone
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Michael Newby
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Jamie Corne wrote:
Matt Carkhuff wrote:from what I have read; covering the barrel does reduce the heat ouput (at least immediate heat) and can make the top hotter. I also have seen instants of videos where they claimed the drafting was reduced (looking for the video now) and that it was less "rockety".

my thought is that with young ones it may be a good idea; just leave some of it exposed like the top 14" or so. I am still gathering parts to build my first RMH so don't take my words as gold yet...


We were thinking about the kids a lot - since one of them will be only 4 in April. She loves to climb too...just our luck.

I will have to check some videos out. It's hard to find videos that go into detail on these things as I don't need so much "opinion" as I do fact...since it's our family we're dealing with here. Thank you so much for the response though - a lot of useful information and much appreciated!


One of the main functions of the barrel is to create a difference in temperature between the hot gases in the heat riser and the cooler gases between the heat riser and the barrel. It's this difference in temperature that creates the rocketing draft - the bigger the difference in temp the better the draft, all other thing being kept constant. If you cover the barrel with cob, the stove works great while the cob is heating up until the cob gets really hot and diminishes that difference in temp.

This doesn't mean that it can't be done, just that you'll have to account for the lack of rocket effect by creating draft some other way.
 
Jamie Corne
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Michael Newby wrote:
Jamie Corne wrote:
Matt Carkhuff wrote:from what I have read; covering the barrel does reduce the heat ouput (at least immediate heat) and can make the top hotter. I also have seen instants of videos where they claimed the drafting was reduced (looking for the video now) and that it was less "rockety".

my thought is that with young ones it may be a good idea; just leave some of it exposed like the top 14" or so. I am still gathering parts to build my first RMH so don't take my words as gold yet...


We were thinking about the kids a lot - since one of them will be only 4 in April. She loves to climb too...just our luck.

I will have to check some videos out. It's hard to find videos that go into detail on these things as I don't need so much "opinion" as I do fact...since it's our family we're dealing with here. Thank you so much for the response though - a lot of useful information and much appreciated!


One of the main functions of the barrel is to create a difference in temperature between the hot gases in the heat riser and the cooler gases between the heat riser and the barrel. It's this difference in temperature that creates the rocketing draft - the bigger the difference in temp the better the draft, all other thing being kept constant. If you cover the barrel with cob, the stove works great while the cob is heating up until the cob gets really hot and diminishes that difference in temp.

This doesn't mean that it can't be done, just that you'll have to account for the lack of rocket effect by creating draft some other way.


We are in no way done with this project - but consulted the pottery company. We bought higher quality clay that is normally used to create high heat fire bricks with - and used it as "slip" as suggested above to us...

The riser is filled with Vermiculite and clay mixed just enough so it holds it shape, but when squeezed...it explodes in my hand. I then mixed a little bit of it heavier with clay to fill in the base of the riser - where you see the "clay" looking material at.

The entire fire chamber was redone using nothing but fire bricks - and then we lined the firebricks on the outside with other bricks.




We ran a test burn with some kindling - and my o my...what a draft! It was cold in the place that we did the test burn so if what you are saying is accurate - that's probably what caused the draft. The fire went sideways and we had minimal to no smoke - even without the other barrel. I was pretty impressed. Today, we're gonna put the outside barrel on and put brick and cob against that blue wall to prevent fire. Good thing too - we got an arctic storm heading our way for this weekend!

Thanks for the information on the barrel. Do you have suggestions for other ways to create the temp difference?
 
Jamie Corne
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One thing that crossed my mind today...

What would happen if we didn't insulate the riser all the way up - but left 12 inches without any insulation? Would that create turbulence...or would it stop the draft? This is purely just a thought-experiment...I'd not dare try it with our first project here.

Just wondering if anyone has done this to see what would happen?
 
Gerald O'Hara
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Jamie,
It isn't much colder in my area of the state than yours but at least you are 1 hour from SF. I am 4 hours away. I'd be better off going to Watertown or Fargo...LOL
One thing that caught my eye was the fact that you are using a galvanized metal for your insulation jacket. I am informed that galvanized metal gives off bad fumes when heated... so you may want to think about that before putting the barrel on and covering it with the cob. (just a thought). One day, I'll have to drive down there and see your RMH. I am in the initial stages of building rocket stoves with steel combustion chambers and chimney and using an old compressor tank for the insulation jacket. I'll let you know how that goes.

I would however like to know where you got those $.50/brick fire bricks? That might be worth a trip down that far.
 
Jamie Corne
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Gerald O'Hara wrote:Jamie,
It isn't much colder in my area of the state than yours but at least you are 1 hour from SF. I am 4 hours away. I'd be better off going to Watertown or Fargo...LOL
One thing that caught my eye was the fact that you are using a galvanized metal for your insulation jacket. I am informed that galvanized metal gives off bad fumes when heated... so you may want to think about that before putting the barrel on and covering it with the cob. (just a thought). One day, I'll have to drive down there and see your RMH. I am in the initial stages of building rocket stoves with steel combustion chambers and chimney and using an old compressor tank for the insulation jacket. I'll let you know how that goes.

I would however like to know where you got those $.50/brick fire bricks? That might be worth a trip down that far.


Hey Gerald! You ready for the arctic freeze this weekend? You're more north so I'm going to assume it's going to get colder and windier up there...hopefully not.



As far as the tube that is galvanized - as far as I know - you have to heat zinc to 900 degrees before it gives off toxic fumes that could harm anyone - but as Ernie has stated on the forum here...it's really not that big of a problem since we are venting outside and the fumes would be so minimal...

I appreciate the sentiments though. Our first complete burn will be highly ventilated - just to be on the safe side. Never hurts to be safe.

That fire brick that we found was at the Habitat for Humanity Restore Store in Sioux Falls. They tore down a house with a massive fireplace - and they got A LOT of the brick that was still usable. From what I understand - many Habitat Restore's across the nation have them from time to time because they tear down many different types of homes - older ones especially, which tend to have fire places. Otherwise, if you go to I-29 brick in Sioux Falls - they are 2.19 a brick - for the 3000 degree F rated bricks (used for kilns).

Watertown doesn't have ANYTHING for rocket stoves. Don't waste your time there. No firebricks - no fire clay - no Vermiculite in the winter - nothing. Brookings either. Hopefully that will change soon, if we can get people to move to rocket stoves and mass thermal heaters.

It would be great to have you come on down (or over as the case might be) and see our rocket baby. Building it hasn't been without its headaches...that's for sure...but this weekend, we're planning on being awfully warm without having to make a bunch of trips out to the woodshed for logs. That...will be nice for a change. And waking up in the morning with it still being quasi-warm instead of bone-chilling cold...we can't wait

I hope to have more conversations with ya - especially about the stoves that you build. Take care and if we don't talk before the storm is over - stay warm and stay safe!
 
Jamie Corne
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So we did the first "actual" burn - with everything put together and of course - things went wrong.

Without the barrel on - we get excellent draft and no smoke from the riser; but put the barrel on - and we get minimal draft and lots of smoke.

Our first thought was that the exhaust was malfunctioning.

Our second thought was that the barrel has too much height from the riser (approximately 4.5-5.0ish inches). I tried closing the feed tube down a bit to see what would happen - nothing. More smoke.

So I took the barrel off and I am reworking the base under the riser and fitting a bigger exhaust tube to the barrel.

If that doesn't work - we'll take the barrel back off - and cut it down about 1.5-2.0ish inches. That will leave us with a 2 inch gap between the riser and the barrel top.

Any other suggestions that we haven't tried yet? (we've essentially been reading this forum for solutions most of the night). Thanks.
 
Peter van den Berg
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Jamie Corne wrote:So we did the first "actual" burn - with everything put together and of course - things went wrong.
Without the barrel on - we get excellent draft and no smoke from the riser; but put the barrel on - and we get minimal draft and lots of smoke.
Our first thought was that the exhaust was malfunctioning.
Our second thought was that the barrel has too much height from the riser (approximately 4.5-5.0ish inches). I tried closing the feed tube down a bit to see what would happen - nothing. More smoke.
So I took the barrel off and I am reworking the base under the riser and fitting a bigger exhaust tube to the barrel.

This exhaust from the barrel to the bench duct, the manifold, is 9 times out of 10 the source of the trouble. There's a minimum size for the top gap, but in practise no maximum at all. I've had a stove running smoothly with a top gap as large as a yard, no problems whatsoever.

Please try this forum link for a good explanation about the ins and outs of the manifold quirks.
 
Devon Olsen
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Jamie Corne wrote:I was wondering about something.

I've seen a lot of rocket heaters and mass thermal heaters where the "barrel" is exposed - and quite ugly. Then I've seen ones like in the picture below.

Does covering the barrel like that reduce the heat output?



perhaps if you were to take this design and provide some "holes" from down near ones feet that fed to the bottom of the barrel... therefore allowing for a convection to occur around the barrel and greatly increasing your initial heat output comparative to this current design, while still keeping the designs seemingly superior long-term heat

honestly, i think thats a great design, and there is a thread on here somewhere about what to do to get rid of that ugly barrel... i think that is thinking in JUST the right direction, i absolutely love it
 
Jamie Corne
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Peter Berg wrote:
Jamie Corne wrote:So we did the first "actual" burn - with everything put together and of course - things went wrong.
Without the barrel on - we get excellent draft and no smoke from the riser; but put the barrel on - and we get minimal draft and lots of smoke.
Our first thought was that the exhaust was malfunctioning.
Our second thought was that the barrel has too much height from the riser (approximately 4.5-5.0ish inches). I tried closing the feed tube down a bit to see what would happen - nothing. More smoke.
So I took the barrel off and I am reworking the base under the riser and fitting a bigger exhaust tube to the barrel.

This exhaust from the barrel to the bench duct, the manifold, is 9 times out of 10 the source of the trouble. There's a minimum size for the top gap, but in practise no maximum at all. I've had a stove running smoothly with a top gap as large as a yard, no problems whatsoever.

Please try this forum link for a good explanation about the ins and outs of the manifold quirks.


The one thing that annoys the heck out of my husband about me is that facts, figures and diagrams do not compute in my head. I have to have a direct "hands on" experience in order to understand how something works. I have literally spent hours...researching these things, reading books, watching videos...and it wasn't until we tried building it "literally" and "physically" that I understand how it works.

I am an ASE certified mechanic.

I am 100% sure that we tried putting a 2cm exhaust pipe on a V8 motor and expected it to work. I had filled the base with cob to "seal up" any holes temporarily to see if it was going to work...a little "too" much..that it pushed up inside and blocked off the exhaust nearly all the way.

We're attempting again tonight - in the arctic freeze we're experiencing. Our old wood stove (traditional) is pulling double duty...but keeping us warm.
 
Jamie Corne
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Devon Olsen wrote:
Jamie Corne wrote:I was wondering about something.

I've seen a lot of rocket heaters and mass thermal heaters where the "barrel" is exposed - and quite ugly. Then I've seen ones like in the picture below.

Does covering the barrel like that reduce the heat output?



perhaps if you were to take this design and provide some "holes" from down near ones feet that fed to the bottom of the barrel... therefore allowing for a convection to occur around the barrel and greatly increasing your initial heat output comparative to this current design, while still keeping the designs seemingly superior long-term heat

honestly, i think thats a great design, and there is a thread on here somewhere about what to do to get rid of that ugly barrel... i think that is thinking in JUST the right direction, i absolutely love it


I thought it was an excellent design as well I cannot take credit though as it's not ours. I wish though lol.

I'm wondering about the holes near the bottom that you talk about. I'm wondering if that would create a "slow down" in the riser...which would result in smoke coming out from those holes...

Would be worth a shot to see if it works though!
 
Devon Olsen
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well those holes should not be in any way connected to any place where it would have smoke venting, it'd simply be a serperate tube if you will that is heated by its proximity to the the hot barrel and insulator, causing the air to rise and creating a convection current
i dont see why there would be smoke unless there was a hole burned in the barrel or something...
 
Jamie Corne
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Devon Olsen wrote:well those holes should not be in any way connected to any place where it would have smoke venting, it'd simply be a serperate tube if you will that is heated by its proximity to the the hot barrel and insulator, causing the air to rise and creating a convection current
i dont see why there would be smoke unless there was a hole burned in the barrel or something...


oooooh!

I thought you meant the holes could be coming directly from under the outer barrel.

Yep, I think I must of been having a blonde moment for sure *blush*

 
Gerald O'Hara
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Jamie Corne wrote: Hey Gerald! You ready for the arctic freeze this weekend? You're more north so I'm going to assume it's going to get colder and windier up there...hopefully not.

As far as the tube that is galvanized - as far as I know - you have to heat zinc to 900 degrees before it gives off toxic fumes that could harm anyone - but as Ernie has stated on the forum here...it's really not that big of a problem since we are venting outside and the fumes would be so minimal...

Well, here it is Sunday AM and it is pretty cold. We got a little fresh white dust last night but that is about it.

Jamie Corne wrote: I appreciate the sentiments though. Our first complete burn will be highly ventilated - just to be on the safe side. Never hurts to be safe.
Old habits from flying with the Navy...always say somthing when it comes to questions of safety. THere is no such thing as "Keeping your mouth shut" if safety is in question. I understand your point. Hopefully it won't get THAT hot inside your barrel.


Jamie Corne wrote: That fire brick that we found was at the Habitat for Humanity Restore Store in Sioux Falls. They tore down a house with a massive fireplace - and they got A LOT of the brick that was still usable. From what I understand - many Habitat Restore's across the nation have them from time to time because they tear down many different types of homes - older ones especially, which tend to have fire places. Otherwise, if you go to I-29 brick in Sioux Falls - they are 2.19 a brick - for the 3000 degree F rated bricks (used for kilns).
My luck they won't have any left and I'll have to pay the $2.10/each. While I can do that, and currently, it is worth it to me to have them than skip that part, I do believe that going the distance with the "right bricks" is the only way to go. I (as I said above) don't like to compromise safety or anthing that would challenge my existence.

Jamie Corne wrote: Watertown doesn't have ANYTHING for rocket stoves. Don't waste your time there. No firebricks - no fire clay - no Vermiculite in the winter - nothing. Brookings either. Hopefully that will change soon, if we can get people to move to rocket stoves and mass thermal heaters.

It would be great to have you come on down (or over as the case might be) and see our rocket baby. Building it hasn't been without its headaches...that's for sure...but this weekend, we're planning on being awfully warm without having to make a bunch of trips out to the woodshed for logs. That...will be nice for a change. And waking up in the morning with it still being quasi-warm instead of bone-chilling cold...we can't wait


I'll let you know when I come by that way. It may be next week since I only work two days a week. I like to plan big trips in advance and since I have to bring my dog, and feed the animals before I leave for the day, I have to do split second planning. I'll skip the stop-over in Watertown though. Since shipping is so brutally expensive out here and very unreliable, I will have to drive my truck to get these items.

Jamie Corne wrote: I hope to have more conversations with ya - especially about the stoves that you build. Take care and if we don't talk before the storm is over - stay warm and stay safe!

You can if you like send me a PM and I will be happy to discuss this with you. I shouldn't put my email address here, I guess.

I got the rocket stove outer jacket built yesterday and I only had one bag of perlite so it didn't fill up very much but now I have to grind the welds (they look awful because the N2 tank wasn't working right at first.) and weld the top on it, make some legs for it and add some spacers for the top to hold a pot. I did manage to boil water on it yesterday though. I had a tea kettle full of ice and in no time at all, I had it whistle. That was really a great feeling. Once I have the insulation in and the top on it, I should be ready to do another one and this time use an old water heater tank that I salvaged and see what I can accomplish.
More as it happens...
 
Jamie Corne
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Gerald O'Hara wrote:
Jamie Corne wrote: Hey Gerald! You ready for the arctic freeze this weekend? You're more north so I'm going to assume it's going to get colder and windier up there...hopefully not.

As far as the tube that is galvanized - as far as I know - you have to heat zinc to 900 degrees before it gives off toxic fumes that could harm anyone - but as Ernie has stated on the forum here...it's really not that big of a problem since we are venting outside and the fumes would be so minimal...

Well, here it is Sunday AM and it is pretty cold. We got a little fresh white dust last night but that is about it.

Jamie Corne wrote: I appreciate the sentiments though. Our first complete burn will be highly ventilated - just to be on the safe side. Never hurts to be safe.
Old habits from flying with the Navy...always say somthing when it comes to questions of safety. THere is no such thing as "Keeping your mouth shut" if safety is in question. I understand your point. Hopefully it won't get THAT hot inside your barrel.


Jamie Corne wrote: That fire brick that we found was at the Habitat for Humanity Restore Store in Sioux Falls. They tore down a house with a massive fireplace - and they got A LOT of the brick that was still usable. From what I understand - many Habitat Restore's across the nation have them from time to time because they tear down many different types of homes - older ones especially, which tend to have fire places. Otherwise, if you go to I-29 brick in Sioux Falls - they are 2.19 a brick - for the 3000 degree F rated bricks (used for kilns).
My luck they won't have any left and I'll have to pay the $2.10/each. While I can do that, and currently, it is worth it to me to have them than skip that part, I do believe that going the distance with the "right bricks" is the only way to go. I (as I said above) don't like to compromise safety or anthing that would challenge my existence.

Jamie Corne wrote: Watertown doesn't have ANYTHING for rocket stoves. Don't waste your time there. No firebricks - no fire clay - no Vermiculite in the winter - nothing. Brookings either. Hopefully that will change soon, if we can get people to move to rocket stoves and mass thermal heaters.

It would be great to have you come on down (or over as the case might be) and see our rocket baby. Building it hasn't been without its headaches...that's for sure...but this weekend, we're planning on being awfully warm without having to make a bunch of trips out to the woodshed for logs. That...will be nice for a change. And waking up in the morning with it still being quasi-warm instead of bone-chilling cold...we can't wait


I'll let you know when I come by that way. It may be next week since I only work two days a week. I like to plan big trips in advance and since I have to bring my dog, and feed the animals before I leave for the day, I have to do split second planning. I'll skip the stop-over in Watertown though. Since shipping is so brutally expensive out here and very unreliable, I will have to drive my truck to get these items.

Jamie Corne wrote: I hope to have more conversations with ya - especially about the stoves that you build. Take care and if we don't talk before the storm is over - stay warm and stay safe!

You can if you like send me a PM and I will be happy to discuss this with you. I shouldn't put my email address here, I guess.

I got the rocket stove outer jacket built yesterday and I only had one bag of perlite so it didn't fill up very much but now I have to grind the welds (they look awful because the N2 tank wasn't working right at first.) and weld the top on it, make some legs for it and add some spacers for the top to hold a pot. I did manage to boil water on it yesterday though. I had a tea kettle full of ice and in no time at all, I had it whistle. That was really a great feeling. Once I have the insulation in and the top on it, I should be ready to do another one and this time use an old water heater tank that I salvaged and see what I can accomplish.
More as it happens...


My husband is a Navy vet He said that in the Navy, "there is no such thing as accidents" and if there is a supposed "accident" it was because the person wasn't doing something while being aware.

Safety is the main thing we argued about over this rocket stove. From galvanized pipe...to exploding bricks...we finally came to a reasonable compromise. It was definitely an experience - and hopefully a streamlined one with time and experience.

We didn't get but 4 to 6 inches of dust down here - but the cold...was another story. Took the garden hose out to do chores and it had a bit of fluid in it from last time I watered the sheep - within 100 yards, it froze inside of the hose which caused us to bring it back in and thaw it - and run the next trip out there before it froze. Sigh...sometimes, it's not so glorious living here in good ol' South Dakota - but I wouldn't change it, at least not right now.

I am a journalist, actually - so my email is pretty widely known. You can email me at either of my addresses if you fancy doing so:

jjbrinkman6525@jacks.sdstate.edu
or
jamie@gcherald.com

There is a permaculture "farm" in Estelline - about 10 miles north of where I live that I covered this past summer. The first in our area that anyone has heard of (other than SDSU's permaculture club). They got some pretty neat stuff going on over there. At the time, I was writing for the Watertown Public Opnion Newspaper as their political, business and environmental (and investigative) reporter. I ended up quitting that job though - due to the unethical nature of the editors there and what they asked me to do.

I will be writing a story very soon about this website as well. I am thinking that the Wall Street Journal is going to be the one to get my bid - either that or Reuters. I'm partial to Reuters...for personal reasons lol. Now if I could just get people whom I PM on this site to actually "respond" it might just happen.

There are so many knowledgeable people on this forum...the story would be absolutely enlightening to some individuals across the nation (and perhaps the world).

Well anyway - I'm looking forward to pictures and more of your progress. I should have a progress report on the morrow

PS: with regard to coming to our home...I have brain cancer, and have to go in for some major stuff soon...but we can talk about that in the email if you like
 
Andor Horvath
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Hi Jaime,

say, if you're a visual learner, please consider downloading Sketchup, it's free.

It will allow you to draw if you're so inclined, otherwise will allow you to download and 'fly through"/examice other peoples models...

lot's of people are using it on this and "the other" rocket discussion board.

[I have no $ interest in the software, in fact am finding frustrating to learn after using Autocad, Cadkey...]

please also check out:

builditsolar.com DIY links/advice and how to's about all things renewable energy related
onestrawrob.com a friend here in WI that is a permaculture hero

hope this helps, contact me via IM or post somehow if there are further food/energy/transportation items I can help with,
sorry to hear the "C" word

Andor
 
Andor Horvath
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examice = examine...

also, are you in a location where you can find "refractories" or foundry supplies in the yellow pagesin a city nearby, if so, ask them about "riser sleeves".

if you can great, but keep it to yourself until my next post....

andor
 
Jamie Corne
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Andor Horvath wrote:Hi Jaime,

say, if you're a visual learner, please consider downloading Sketchup, it's free.

It will allow you to draw if you're so inclined, otherwise will allow you to download and 'fly through"/examice other peoples models...

lot's of people are using it on this and "the other" rocket discussion board.

[I have no $ interest in the software, in fact am finding frustrating to learn after using Autocad, Cadkey...]

please also check out:

builditsolar.com DIY links/advice and how to's about all things renewable energy related
onestrawrob.com a friend here in WI that is a permaculture hero

hope this helps, contact me via IM or post somehow if there are further food/energy/transportation items I can help with,
sorry to hear the "C" word

Andor


Hey Andrew,

SketchUp. I recently began using it, but it's a bit different from other AutoCad programs that I'm used to using. I think though, that my favorite part about it is the xray view. My husband used to work in a foundry *grin* but that was when he was young (lol he'll read this later and give me heck for saying that lol).

I appreciate the thoughts - especially about SketchUp. We actually downloaded it a couple weeks ago in order to view a rocket kitchen design that I had got in the email not knowing that I had to have a program other than what I already had to open it. After dinking around with it for about 3 hours - I got the general "gist" of how to work it, although trying to design with it is gonna take me probably another entire day to get it streamlined.

We tried again last night with our rocket stove. It worked and heated...but wasn't as rockety as we'd like it. It's a moderate draft...but I still think we have some work to do to it. Some pics:



Took a negative shot to show the smoke being sucked into the burn chamber instead of out into the room:






We gotta find a way to create more of a draft to make it rocketier. When the barrel is off - it gets really good draft. When the barrel and exhaust are on - it reduces the draft a tad bit.





We're still working on the feed tube - so when we get that done, it might promote draft. As you can see - I just had a stick holding up the upper brick there.





 
Jamie Corne
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Ok, update.

So we burned a second time today and was going to let it burn for a few hours instead of just for an hour - to see how it would do.

I am noticing a problem right off the bat. The wood doesn't want to stay lit. So we thought perhaps we were using too thick of wood. We sliced it down into slivers.

About 15 minutes into the burn, I noticed smoke coming out of the exhaust. Sigh....

Ventilator mask comes in at this point. /not amused.

So I pulled the exhaust tube off while it was still smoking to get a look into the barrel. See images below:













So about 5 minutes along of having the exhaust tube off - the smoke tapered down...but didn't go away completely. But odd - the fire went out shortly after the smoke started coming out.

So, I'm no "fire engineer" but I know that in order for fire to occur - it must get oxygen. It has plenty of oxygen. The wood is sitting in the feed tube as such (in the picture below, however, the outer barrel is not on):



We have very little "suction" with regard to the fire....but the smoke is sucking just fine into the burn chamber.

Now...I'm stumped and researching again.

Any thoughts to help me along?

 
Peter van den Berg
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Jamie Corne wrote:Any thoughts to help me along?

Usually, the second largest problem is the exhaust. When this stove is built inside a house or shed which is high inside and/or do consist of more than one floor there ought to be trouble. Especcially when the exhaust is leading straight outside horizontal without vertical stack. A dryer vent style exhaust is only possible inside a one storey shack equipped with an airtight roof. Read this article about the question: Is Your House a Better Chimney Than Your Chimney?

So, try to add a vertical stack, preferably reaching above the eaves. The stove will run better 99 times out of 100.
 
Jamie Corne
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Peter Berg wrote:
Jamie Corne wrote:Any thoughts to help me along?

Usually, the second largest problem is the exhaust. When this stove is built inside a house or shed which is high inside and/or do consist of more than one floor there ought to be trouble. Especcially when the exhaust is leading straight outside horizontal without vertical stack. A dryer vent style exhaust is only possible inside a one storey shack equipped with an airtight roof. Read this article about the question: Is Your House a Better Chimney Than Your Chimney?

So, try to add a vertical stack, preferably reaching above the eaves. The stove will run better 99 times out of 100.


Would that increase the draw because if it wouldn't - we barely have "any" draw whatsoever when the exhaust pipe is on. It's gonna take quite a bit of energy to get that heavy smoke to to up that vertical tube...isn't it?

Another question...

Do Erika and Ernie come on this forum anymore? I've PM'd Erika over a week ago with no reply and I've emailed Ernie with questions....

I appreciate your helping Peter.
 
Peter van den Berg
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Jamie Corne wrote:It's gonna take quite a bit of energy to get that heavy smoke to to up that vertical tube...isn't it?

No, it isn't. Smoke will go up the stack when it's warmer than the outside air, that's all. Gases of higher temperature are expanded, therefore lighter and tend to rise. So this "heavy" smoke do get it's rising energy from the earth's gravity.

(Hope this is clear, I'm wrestling with the English language all the time.)
 
Jamie Corne
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Peter Berg wrote:
Jamie Corne wrote:It's gonna take quite a bit of energy to get that heavy smoke to to up that vertical tube...isn't it?

No, it isn't. Smoke will go up the stack when it's warmer than the outside air, that's all. Gases of higher temperature are expanded, therefore lighter and tend to rise. So this "heavy" smoke do get it's rising energy from the earth's gravity.

(Hope this is clear, I'm wrestling with the English language all the time.)


See the problem with running it vertically is that we are going to be running it into a thermal mass and then venting it outside after the mass has been laid...

I am actually getting thoroughly frustrated - which is highly unusual for me during a project that involves problem solving.

If one looks at it like an algebraic problem...something in the line of reasoning isn't adding up.

We are getting sideways fire - but not "enough."

We are getting draft - but not "enough"

We are getting smoke coming out of the horizontal feed tube - just a little

We are getting smoke coming out the flue - a lot.

Now because we've taken the barrel off - which completely solved the smoke issue as well as the draft issue - the problem has to be between the barrel and the exhaust somewhere.

Arg...
 
David Corne
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Peter Berg wrote:
Jamie Corne wrote:It's gonna take quite a bit of energy to get that heavy smoke to to up that vertical tube...isn't it?

No, it isn't. Smoke will go up the stack when it's warmer than the outside air, that's all. Gases of higher temperature are expanded, therefore lighter and tend to rise. So this "heavy" smoke do get it's rising energy from the earth's gravity.

(Hope this is clear, I'm wrestling with the English language all the time.)


Hello Peter, and thank you for your input and continued interest.

We had considered a vertical run for a temporary solution, which would make our rmh into a conventional woodstove with a heat exchanger, but that would be to admit defeat. we are determined to have a honest to goodness rmh.
 
Devon Olsen
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i see nothing non-RMH about an elevated "chimney" after all the mass
the main reason i would say it is not getting draft would be taht it has no rise at the other end, for GOOD drafting to occur the exhaust has to exit higher than the feed comes in
i would first try simply making sure that the exhaust is higher than the barrel before making it higher than the whole house
the warmed air rising out of the exhaust creates a vacuum of sorts and pulls air through the rest of the setup, if the exhaust isnt higher than the barrel (theoretically the highest point in the design) than the vacuum is weak and doesn't have enough power to really pull it through and create that rocketty goodness

in a cherokee fire pit (im calling it cherokee because i forgot the name of the tribe that did this and it sounds right to me) is basically two holes close to each other and connected at the bottom, burning your fire at the bottom of the lower hole created a draft and sucked the fire up through the second hole, which was higher up, creating less smoke and concentrating heat for cooking, also saving fuel, the fire pit doesn not work very well, if at all, if the exhaust pit is not higher than the burn pit
and i think thats your main problem here, the heat goes to the highest point, working against the draft and slowing it down, also preventing burning past that point because any oxygen that does manage to get drafted in gets smothered with CO2 due to this
 
Jamie Corne
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Devon Olsen wrote:i see nothing non-RMH about an elevated "chimney" after all the mass
the main reason i would say it is not getting draft would be taht it has no rise at the other end, for GOOD drafting to occur the exhaust has to exit higher than the feed comes in
i would first try simply making sure that the exhaust is higher than the barrel before making it higher than the whole house
the warmed air rising out of the exhaust creates a vacuum of sorts and pulls air through the rest of the setup, if the exhaust isnt higher than the barrel (theoretically the highest point in the design) than the vacuum is weak and doesn't have enough power to really pull it through and create that rocketty goodness

in a cherokee fire pit (im calling it cherokee because i forgot the name of the tribe that did this and it sounds right to me) is basically two holes close to each other and connected at the bottom, burning your fire at the bottom of the lower hole created a draft and sucked the fire up through the second hole, which was higher up, creating less smoke and concentrating heat for cooking, also saving fuel, the fire pit doesn not work very well, if at all, if the exhaust pit is not higher than the burn pit
and i think thats your main problem here, the heat goes to the highest point, working against the draft and slowing it down, also preventing burning past that point because any oxygen that does manage to get drafted in gets smothered with CO2 due to this


Here is a sideways angle view. Our exhaust is higher than the feed tube:

 
Devon Olsen
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I should start this one by saying i havent built one myself but from my understanding of how it all works, from fire itself to draft creation etc etc
i would say that the reason you are getting any draft at all would be because the exhaust is higher than the feed tube, but i would assume it needs to be higher than the barrel to create a STRONG draft
another thing that can affect it, how much length do you have on your exhaust, to a certain extent making it longer creates a stronger vacuum when you need it, helping to create a stronger pull
for instance 20 ft of piping would be weaker than 30 ft of piping in your exhaust

another question, is all the exhaust stuff mostly airtight? i would think a small hole could greatly effect the usefulness of the draft
 
Jamie Corne
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Devon Olsen wrote:I should start this one by saying i havent built one myself but from my understanding of how it all works, from fire itself to draft creation etc etc
i would say that the reason you are getting any draft at all would be because the exhaust is higher than the feed tube, but i would assume it needs to be higher than the barrel to create a STRONG draft
another thing that can affect it, how much length do you have on your exhaust, to a certain extent making it longer creates a stronger vacuum when you need it, helping to create a stronger pull
for instance 20 ft of piping would be weaker than 30 ft of piping in your exhaust

another question, is all the exhaust stuff mostly airtight? i would think a small hole could greatly effect the usefulness of the draft


That particular piece of galvanized pipe that we're using as a test exhaust that will eventually lead into the thermal mass..is about 4 feet long.

I haven't seen any leaks with any smoke or steam coming out anywhere around the unit...so I'm thinking we're okay as far as leaks go.

It is confusing once you actually begin making these. It looks so easy on the screen...but boy o boy...does it ever get complicated and the questions just start flowing once you're knee deep in the project lol.
 
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