Great idea. I rebuilt mine much the same way, only I used 1/4" steel for the baffle and it's warped beyond repair from the high temps of the secondary tubes.. My next step is to use firebrick on an angle iron frame for the upper baffle, which will keep the heat in the firebox, and won't warp. It's unbelievable to see hardly no flame on the wood and the secondaries burning like a gas burner. Lot less wood and alot hotter fire.
My first burners were galvanized pipe. They lasted two years. Believe it or not but i used an old barbeque burner this year and so far it's working great. You did a great fab job on yours. You won't be sorry. Just be sure to burn really dry wood. I'ts amazing how much more heat you'll get out of your wood.Great job and thanks for sharing.
I know that cold air from the attic is way more dense than super hot air. Way more oxygen for the burn. The down side, you need outside air inlet right near the stove ??? Otherwise you create a vacuum in the entire house which will cool the living quarters. Please let me know if you disagree with my logic Sir ?? Thanks
Good video, thank you. I think i've enhanced the pre-heating of air in the central tube (my own one is different but same purpose) by inserting a sheet of metal on wich i've cut a lot of little wings to create a turbulent air flow (
Nice work! I watch a LOT of RM videos and most of them don't seem to put much thought into the engineering of them. How refreshing to see someone FINALLY using their head and skills to improve this design,. I really appreciate your sharing. I hope that when you are done you will gift us with some detailed plans and description documents. That would be an awesome contribution to the commons. One thought: Have you considered running cold-air feed lines through the exterior walls of your space and into the new burners, thus feeding outside air and reducing the loss of warm air from your interior space?
Zerkbern yeah....that may be in an extra video after the next one. I'm going to first install a water heat exchange in the upper chamber and see if it heats the fish water enough. If the air is still warming more than the water, I was thinking about basically covering part of the sides in sheet metal with a gap between the stove and metal, and let the hot air that's captured in there get sucked into the secondary burners. Of course I don't want to contain too much heat inside the stove because then i'll get too much loss up the stack.
Next time you cut holes, drill you corners out, that way it leaves rhe corners rounded, so that as heat expands and contracts it wont start cracking in one or more corners.
nice to se ppl retrofit a "clean burn" system in to old stuff. the one you have is not easy to retrofit eater.. an old Jøtul 60cm is rely easy to retrofit in comparison. Here in norway just about every woodburner that have been sold the last 10-15 yers is clean burning. the first one we got was a Jøtul 201 about 30 yers ago. it was the first and ofc constructed a bit wrong so it "melted" the inside from normal use and did not last to long. Btw in norway 10-15% of all energy usage overal in the winter time is from wood burning ;) they say the power grid had collapsed without wood burner's. where i'm at now we onely have two (and one more to install) wood burner's.. in the old house we had it was 6 of them and all was needed to keep the old house up to temp during the cold month. and yes we use TONS of wood!!!
If the air is being drawn from outside the stove, its really not, "wood gas" being ignited but literal hot air. If you could somehow draw air from under the fire and route it up then that would be the actual wood gasses being ignited. I'm currently puzzling out how to do something like this in my diy stove. Half cat rims and half a hot water tank.
My stove is nothing like this. Can you explain a basic stove with a sliding secondary vent? Where is the secondary air coming from? I see no openings apart from an unclosable slit at the top from which black smoke issues
@1:30, You are saying that the secondary air doesn't have much time to pre-heat. Not only that, but whatever heat it gains, it takes it from the same place in the burn chamber, where it then mixes out with the products of gasification, which are supposed to be afterburnt there. That is kind of pointless, whatever temp you gain in the secondary air, you will lose the same temp (well, energy, to be precise) in the combustible gases. No fly! Have you been thinking about making a shrewd around the chimney stack, with the opening at the top of the shrewd, and sucking the air in through there? Had to be done very carefully, because you might create another unwanted "chimney" this way. Might require forced air. But this way, you are only using waste heat, and secondly, when there is counter-flow of the gases in the heat exchanger (i.e., waste heat/exhaust goes upwards, but the secondary air gets around it downwards), the heat exchange is very efficient (can be nearly complete exchange of temps, as exemplified by the domestic heat recuperating units.) All the best,
There is still an added efficiency by just burning these secondary gasses so the overall net gain is better. The additional heat that is produced will out weight what is "lost" by not preheating. I believe that even the modern wood stove just take ambient air for their secondary burn. It would certainly help using some kind of coaxial chimney, but it really isn't worth my time and expense dealing with it. ;-)
Just yank burners out of free or garbage bbq’s. Friction fit them on. They’re plentiful and basically disposable and free.I randomly encountered a half dozen bbq’s being thrown out and have a ton of them now
Instead of cutting those holes square, you could have just drilled large round holes and it would have worked fine. The square tube would have still welded over the round hole easily.. Nice little setup
Where i live in Ontario had to get rid of my old stove because the insurance company would not insure my home unless my stove was EPA approved ? careful look into whether your covered by your insurance with a homemade stove chances are NO???
great video. does it matter where the air enters the stove. I have a yeoman and used the rear boiler tube hole for the secondary burn tubes. these are 1 inch but it doesn't work at all. very disappointing.
So there’s no way to regulate the air coming in the second burner?Seems like that would be necessary for a longer burn at night, and from letting the wood get all the air it wants and burning up faster and creating excessive heat .
usually there's some smoke when I first start it up and then load too much wood into it. Usually I can just manually open the damper for a minute to stokeit up a bit more.
Hi Could You tell me what size holes you drilled in your Burner tube? I have a small 20lb propane tank stove for my ice shack and i have made a burner but with only a 3 inch flue pipe I am torn as to what size of holes to drill. I am leaning toward 5/32. Any thoughts would be appreciated Thanks.
I have a Question for you as you seem to have a really good grasp on engineering etc. Ok i built this 20lb propane tank stove 3 inch flue. I built a secondary burner two 1 inch square tubing 12" with a 7.5"cross piece to join them. I did not have the space To run another length of tube like you did to really preheat things. The secondary burner is at the very top so i am hoping it will get the air hot enough in a 12 inch run. My dilemma is I have to drill my holes in the 7.5 cross piece before i weld the secondary burn tube in place and I cannot decide what size to make the holes. My thoughts are the 3 inch flue does not draw a alot of air, if i make the holes small will it draw enough air out of a small hole. If I make the holes to big the air exchange inside the tubes will be so fast the air will not heat up enough to get a good secondary ignition. I dont have a ton of room for holes either so my drill holes probably wont equal the air intake size of the square tube. Sorry for the long rant. Any thoughts? Thanks
@@Bigelowbrook I'm going to have a go mine is a bit tricky it's a boiler stove I'll have to put on my thinking hat I'll probably use stainless steel box or pipe is you pipe inch. 👍
@@mazman8343 stainless is the best option! I was just sort of experimenting so i didn't care about the material....of course temporary has become permanent! ;-)
a plasma cutter would be a lot faster than your grinder. it would cost about the same as your welder , but you'd not need to use the cutting disk except for delicate cutting or grinding
How much secondairy air do I need, because with mine stove it do not ignite, but the preheat system is oke,, it looks that I get to much air what cool down the fire.
Not really understanding the mechanism of pre-cheating of the air. As air getting hotter the less dense and less caloric is, hence the intercooler used in cars.
Yes, would someone explain why preheated air is good for combustion? Cool/ cold air is denser and more oxygen rich. Wouldn't the fire burn hotter with more oxygen-rich air? Maybe we should preheat the air that enters our car motors and get a more efficient combustion...the gearheads out there would get a chuckle outa that.
@@adollarshort1573wood gases require a temperature of many hundred degrees - I forget the exact number - before they will light even in the presence of enough oxygen and if you flood the wood gases with too much cold air, the gases never light off at all, regardless of the oxidizer density, sending the wood gases up the stack un-combusted and semi-diluted instead. It has always been a balancing act with wood fires to keep these gases hot enough to combust while mixing in secondary air. Modern stoves, furnaces, masonry heaters, etc. obtain secondary combustion with hot fireboxes, lined with semi-insulating material like firebrick and somehow heating the secondary air enough for light off. Stoves, with their somewhat light mass and relative small size, have to carefully preheat and inject the secondary air to get secondary combustion. The secondary air has to be injected above the coals/wood as well because the solid, burning carbon will consume just about all the oxygen you attempt to run through it, no matter how fast you try. Therefore the secondary air must enter above the solids, but then the question becomes, are you going to over-cool that secondary air/wood gas mixture and fail to ignite it? Another technique is to use a catalytic honeycomb combuster which works by chemically allowing/forcing secondary combustion at a lower, more easily obtained temperature, but catalytic combustors generally restrict air flow, are prone to failure due to fuel contamination, and generally wear out after several years. Still, for very low fires, combustors work. There are so-called hybrid stoves that have both secondary air tubes and catalytic combustors and can be operated with one or the other, depending on the desired stove firing rate.
@@Bigelowbrook Thank you for the reply. Do you recall how large the holes you drilled were and the spacing? Or does it make much difference? Thanks again.
srsly stop designing stoves dude... i watched the first video of your rocket stove and thought immediatly that it will light the wood supply at some point. how can u be that inconsiderate with such dangerous things?
This stove has been running fine for a few years now. Are you a professional stove designer that is a leading expert in retrofitting old stoves and can actually contribute some knowledge to the advancement of wood burning? Perhaps you could clarify which part is "dangerous".
My kind of information, quick, complete without a lot of unnecessary fluff...and nice craftsmanship!
Great idea. I rebuilt mine much the same way, only I used 1/4" steel for the baffle and it's warped beyond repair from the high temps of the secondary tubes.. My next step is to use firebrick on an angle iron frame for the upper baffle, which will keep the heat in the firebox, and won't warp. It's unbelievable to see hardly no flame on the wood and the secondaries burning like a gas burner. Lot less wood and alot hotter fire.
Did you see longer burn times when adding secondary burners
My first burners were galvanized pipe. They lasted two years. Believe it or not but i used an old barbeque burner this year and so far it's working great. You did a great fab job on yours. You won't be sorry. Just be sure to burn really dry wood. I'ts amazing how much more heat you'll get out of your wood.Great job and thanks for sharing.
Did you have a long run of tube to allow the air to preheat alot before your bbq burner?
Nice design and secondary burn idea there.
I know that cold air from the attic is way more dense than super hot air. Way more oxygen for the burn. The down side, you need outside air inlet right near the stove ??? Otherwise you create a vacuum in the entire house which will cool the living quarters.
Please let me know if you disagree with my logic Sir ?? Thanks
I have been looking for a video like yours for days. you did a great job just putting it in simple terms. Thank you!
Great job. Round tubing and radius turns at the junction will give you much smoother and greater air flow in smaller tubing.
Good video, thank you. I think i've enhanced the pre-heating of air in the central tube (my own one is different but same purpose) by inserting a sheet of metal on wich i've cut a lot of little wings to create a turbulent air flow (
Nice work! I watch a LOT of RM videos and most of them don't seem to put much thought into the engineering of them. How refreshing to see someone FINALLY using their head and skills to improve this design,.
I really appreciate your sharing. I hope that when you are done you will gift us with some detailed plans and description documents. That would be an awesome contribution to the commons.
One thought: Have you considered running cold-air feed lines through the exterior walls of your space and into the new burners, thus feeding outside air and reducing the loss of warm air from your interior space?
Zerkbern yeah....that may be in an extra video after the next one. I'm going to first install a water heat exchange in the upper chamber and see if it heats the fish water enough. If the air is still warming more than the water, I was thinking about basically covering part of the sides in sheet metal with a gap between the stove and metal, and let the hot air that's captured in there get sucked into the secondary burners. Of course I don't want to contain too much heat inside the stove because then i'll get too much loss up the stack.
Bigelow Brook Farm (Web4Deb)
Awesome. It is clear you are investing in some significant cogitation on this project. I'm looking forward to updates!
A great addition Rob..
Hope you & ours are having a great day mate..
Cheers..
Next time you cut holes, drill you corners out, that way it leaves rhe corners rounded, so that as heat expands and contracts it wont start cracking in one or more corners.
I love the feeling of a woodstove.
nice to se ppl retrofit a "clean burn" system in to old stuff. the one you have is not easy to retrofit eater.. an old Jøtul 60cm is rely easy to retrofit in comparison. Here in norway just about every woodburner that have been sold the last 10-15 yers is clean burning. the first one we got was a Jøtul 201 about 30 yers ago. it was the first and ofc constructed a bit wrong so it "melted" the inside from normal use and did not last to long.
Btw in norway 10-15% of all energy usage overal in the winter time is from wood burning ;) they say the power grid had collapsed without wood burner's. where i'm at now we onely have two (and one more to install) wood burner's.. in the old house we had it was 6 of them and all was needed to keep the old house up to temp during the cold month. and yes we use TONS of wood!!!
Seasons greetings, Good to see you experimenting still
If the air is being drawn from outside the stove, its really not, "wood gas" being ignited but literal hot air. If you could somehow draw air from under the fire and route it up then that would be the actual wood gasses being ignited. I'm currently puzzling out how to do something like this in my diy stove. Half cat rims and half a hot water tank.
Wood gases are just the smoke coming up from the wood. It meets the hot air and ignites.
Excellent. Very well explained
Fuel for the brain. Thank you
an excellent solution of a wood stove is the high-performance stove.
Thanks for sharing! I am looking for ways to improve my fireplace. your way is great.
next time cut in 45° , it makes it a lot easier ;)
Just making burner yes 45 works great
My stove is nothing like this. Can you explain a basic stove with a sliding secondary vent? Where is the secondary air coming from?
I see no openings apart from an unclosable slit at the top from which black smoke issues
LOVE these videos-thank you bigtime for doing them!
@1:30, You are saying that the secondary air doesn't have much time to pre-heat. Not only that, but whatever heat it gains, it takes it from the same place in the burn chamber, where it then mixes out with the products of gasification, which are supposed to be afterburnt there. That is kind of pointless, whatever temp you gain in the secondary air, you will lose the same temp (well, energy, to be precise) in the combustible gases. No fly!
Have you been thinking about making a shrewd around the chimney stack, with the opening at the top of the shrewd, and sucking the air in through there? Had to be done very carefully, because you might create another unwanted "chimney" this way. Might require forced air. But this way, you are only using waste heat, and secondly, when there is counter-flow of the gases in the heat exchanger (i.e., waste heat/exhaust goes upwards, but the secondary air gets around it downwards), the heat exchange is very efficient (can be nearly complete exchange of temps, as exemplified by the domestic heat recuperating units.)
All the best,
There is still an added efficiency by just burning these secondary gasses so the overall net gain is better. The additional heat that is produced will out weight what is "lost" by not preheating. I believe that even the modern wood stove just take ambient air for their secondary burn. It would certainly help using some kind of coaxial chimney, but it really isn't worth my time and expense dealing with it. ;-)
Just yank burners out of free or garbage bbq’s. Friction fit them on. They’re plentiful and basically disposable and free.I randomly encountered a half dozen bbq’s being thrown out and have a ton of them now
You rock! Thanks for sharing your adventures!
Instead of cutting those holes square, you could have just drilled large round holes and it would have worked fine. The square tube would have still welded over the round hole easily.. Nice little setup
Imagine installing that piece while their was a fire inside 😂.
Excellent stuff bro
Hola!! Este sistema se puede implementar en la estufa rusa con un horno?
You are very fun to watch reminds me of me.
It seems to me that it would have been a lot easier to build this out of standard black pipe.
Where i live in Ontario had to get rid of my old stove because the insurance company would not insure my home unless my stove was EPA approved ? careful look into whether your covered by your insurance with a homemade stove chances are NO???
Thats Commi Canada for ya!
Do not be Naive insurance companies will not pay if you do not comply?? better to ask and find out then lose everything because of it? @@dusty1498
great video. does it matter where the air enters the stove. I have a yeoman and used the rear boiler tube hole for the secondary burn tubes. these are 1 inch but it doesn't work at all. very disappointing.
Good job ! Happy Holidays
Good video but let me ask what the music is. I've heard it before but can't place it. Please tell me.
So there’s no way to regulate the air coming in the second burner?Seems like that would be necessary for a longer burn at night, and from letting the wood get all the air it wants and burning up faster and creating excessive heat .
for my application, I didn't need to regulate the burn rate since I'm mainly putting the heat into the water mass.
Nice video
Very good job.
So could this same setup be used in an Old Barrel stove?
Good job! Are you getting any smoke out of the flue now that the secondary is in action?
usually there's some smoke when I first start it up and then load too much wood into it. Usually I can just manually open the damper for a minute to stokeit up a bit more.
The time to hesitate is thru.
No time to wallow in the mire.
If I were to say to you.
Come on baby light my secondary burnners.
buildeed mine today.. does not work as good as yours.. i cleaned the stove i think the real benefits come when the air from below is blocked
Hi Could You tell me what size holes you drilled in your Burner tube? I have a small 20lb propane tank stove for my ice shack and i have made a burner but with only a 3 inch flue pipe I am torn as to what size of holes to drill. I am leaning toward 5/32. Any thoughts would be appreciated Thanks.
I think it was 1/16"...that was long ago!
@@Bigelowbrook Thanks ! How long did your burners last ? Is the stove still in operation?
@@dusty1498 Still going!
@@Bigelowbrook Nice👍
I have a Question for you as you seem to have a really good grasp on engineering etc. Ok i built this 20lb propane tank stove 3 inch flue. I built a secondary burner two 1 inch square tubing 12" with a 7.5"cross piece to join them. I did not have the space
To run another length of tube like you did to really preheat things. The secondary burner is at the very top so i am hoping it will get the air hot enough in a 12 inch run. My dilemma is I have to drill my holes in the 7.5 cross piece before i weld the secondary burn tube in place and I cannot decide what size to make the holes. My thoughts are the 3 inch flue does not draw a alot of air, if i make the holes small will it draw enough air out of a small hole. If I make the holes to big the air exchange inside the tubes will be so fast the air will not heat up enough to get a good secondary ignition. I dont have a ton of room for holes either so my drill holes probably wont equal the air intake size of the square tube. Sorry for the long rant. Any thoughts? Thanks
Great idea. I built a rocket stove but tired of having to refuel it every 20 or 30 minutes
Use pallets
Great Job! I love "how to" videos!
Superb as always.
so you are in effect over riding the auto dampener, overheating the metal and causing it to deteriorate .
Excellent
Great video Question how long will the box steel last
I figured a year or two but it's still in great shape!
@@Bigelowbrook I'm going to have a go mine is a bit tricky it's a boiler stove I'll have to put on my thinking hat I'll probably use stainless steel box or pipe is you pipe inch. 👍
@@mazman8343 stainless is the best option! I was just sort of experimenting so i didn't care about the material....of course temporary has become permanent! ;-)
how can it get hotter without the secondary burn? should be the other way around.
Very good info. Thanks!
Pic of the baffle ? 😊
how close does the secondary need to be by the wood? im gonna make a vertical stove with more upper space
it needs to be near a flame so the gas can be ignited.
What temperature does your 2ndary combustion occur ?
I'm looking forward to updates! owsome ,thanks for the video...
Very nice , thanks for sharing!
Yo. Nice wheel horse!!
great job.
a plasma cutter would be a lot faster than your grinder. it would cost about the same as your welder , but you'd not need to use the cutting disk except for delicate cutting or grinding
I picked up the welder for $100 at a yard sale. If only I could get a cutter for that price....
Bigelow Brook Farm (Web4Deb)
and it works!? holy wow!
dufusrunescape Low risk - It helped that I knew the guy...he was retiring and moving to FL. ;-)
Bigelow Brook Farm (Web4Deb)
we always give a better deal to people we know too. and 4-H ers ,FFAers.
Nice! What size are the holes you drilled?
I don't remember....probably whatever small bit I found. ;-) I would guess 1/16"
Do you guys have that cotton type layer where the smoke goes through
How much secondairy air do I need, because with mine stove it do not ignite, but the preheat system is oke,, it looks that I get to much air what cool down the fire.
Same with mine.
I think it best not to bring stove over 550 as you burn the metal.
good job
make tubes from stainless steel
Do you still have a chimney damper? Or are you regulating the fire with the air intake?
there's no damper. It's all regulated from the intake
Not really understanding the mechanism of pre-cheating of the air. As air getting hotter the less dense and less caloric is, hence the intercooler used in cars.
Yes, would someone explain why preheated air is good for combustion? Cool/ cold air is denser and more oxygen rich. Wouldn't the fire burn hotter with more oxygen-rich air?
Maybe we should preheat the air that enters our car motors and get a more efficient combustion...the gearheads out there would get a chuckle outa that.
@@adollarshort1573wood gases require a temperature of many hundred degrees - I forget the exact number - before they will light even in the presence of enough oxygen and if you flood the wood gases with too much cold air, the gases never light off at all, regardless of the oxidizer density, sending the wood gases up the stack un-combusted and semi-diluted instead. It has always been a balancing act with wood fires to keep these gases hot enough to combust while mixing in secondary air. Modern stoves, furnaces, masonry heaters, etc. obtain secondary combustion with hot fireboxes, lined with semi-insulating material like firebrick and somehow heating the secondary air enough for light off. Stoves, with their somewhat light mass and relative small size, have to carefully preheat and inject the secondary air to get secondary combustion. The secondary air has to be injected above the coals/wood as well because the solid, burning carbon will consume just about all the oxygen you attempt to run through it, no matter how fast you try. Therefore the secondary air must enter above the solids, but then the question becomes, are you going to over-cool that secondary air/wood gas mixture and fail to ignite it?
Another technique is to use a catalytic honeycomb combuster which works by chemically allowing/forcing secondary combustion at a lower, more easily obtained temperature, but catalytic combustors generally restrict air flow, are prone to failure due to fuel contamination, and generally wear out after several years. Still, for very low fires, combustors work. There are so-called hybrid stoves that have both secondary air tubes and catalytic combustors and can be operated with one or the other, depending on the desired stove firing rate.
How long did the secondary burners last?
I'm still on the original one!
@@Bigelowbrook Thank you for the reply. Do you recall how large the holes you drilled were and the spacing? Or does it make much difference?
Thanks again.
Great--- Keep at it Terry
Do you ever have problems with exhaust coming out the secondary air intake?
nope. There's enough draft going up the chimney that the air is always getting sucked in. Even on windy days I haven't seen any problems
That's good to know. I'm looking at doing a similar upgrade on a 1980s vintage stove.
Amigo... hice el mismo quemado y no hace nada de nada
Awesome!
that will produce a tremendous amount of heat. All of that work will be destroyed in one year, unless you use titanium. Nice work though
It's still running great after all these years! The water tank gets the brunt of the heat so that metal is staying cool.
temporary? hell no, will work for as long as the stove works
It still works!
The first part plźzzxx
That was great man, I know how it work now. thank you.
сварочные соединения в высокотемпературной топке -слабое место
всей конструкции данной печки.
Muy buenos
Нешта я не зразумеў навошта гэта?
Time to buy a plasma cutter you will never be sorry that you did especially for work what you're doing
yeah, I'd love to get one some day.
srsly stop designing stoves dude... i watched the first video of your rocket stove and thought immediatly that it will light the wood supply at some point. how can u be that inconsiderate with such dangerous things?
This stove has been running fine for a few years now. Are you a professional stove designer that is a leading expert in retrofitting old stoves and can actually contribute some knowledge to the advancement of wood burning? Perhaps you could clarify which part is "dangerous".