Another set of bricks out front to lengthen the burn chamber before the flames go vertical would improve efficiency. Fire brick has less thermal mass, it won't absorb as much heat and should be insulated as well. the horizontal to vertical transition area is where proper mixing and combustion efficiency occur. A secondary air inlet might help, it might also hurt by cooling the combustion process. In all the stoves I've built I've always strove to see only heat waves exit the stack, no smoke and no flames means everything was combusted. These are fun to play with. Nice documentation of the build and initial firing.
Helpful Hint: Before using the perlite, soak it in water for about 24 hours. The cement won't absorb as much water out of it, and it's easier to mix and to form. GREAT video, GREAT idea.
Ha! Yup. :-) Good luck with your build. You should look at a rocket mass heater. It might be better for heating an interior space. Thanks for watching.
Rocket mass heaters are awesome! I’ve seen some with an exhaust “pool” bank that works well. Put a smaller one on castor wheels so you can move it around.
My suggestion is on filling... it looks like it would be a lot easier if you put an old plastic bag and a rubber band over the top of the burner while you add the first layer of concrete and most,of the perlite. It would probably also help to fold some paperboard like the side a cereal box into a shape somewhere between a ramp and a funnel to help guide in the perlite also. Great build, thanks for sharing.
Ian, great suggestions! The cement an perlite filling was trickier than I thought it would be. I was moving fast by that point in the build and didn’t stop to think. :-) Thanks for the feedback.
Good idea. One concern I had firing the stove was pressure build up. As it was, steam from the moist cement was venting through the gap between the cans. I suppose I could epoxy sections of the connection, leaving room for air movement. Thanks for the feedback. Thanks for watching.
Hey Tom, One way to make the build a little simpler is as you said by using #10 cans. Obviously you used what you had on hand - paint cans. But if you use #10 cans they have no "lip" like paint cans and then you can use a 6 inch diameter HVAC (or stovepipe if your local Lowes/Home D. has them) connector (coupling) to put the two or more cans together instead of the metal bands and screws. You may still need to use a few screws to hold it together if you're planning on moving it around. You can also use tin snips (aviation shears) to cut out the hole in the bottom - easier (IMHO) than using the angle grinder. An easy free source for #10 (1 gallon) cans is your local Mexican (and probably other) food restaurant. They usually get beans and or chiles in this size can. You can either raid they're dumpster after hours (my method), or you could probably just ask them if they have any on hand. Also this whole process can be done without lining the inside at all. Just using the #10 cans. A bit less efficient/stable sure, but if you have the wood on hand (I work in a cabinet shop so...) and aren't prone to knocking things over...it still works fine. You could make the pot stand out of a 2nd HVAC connector in the same manner as you did here. There is also another can size (I don't know the number) that happens to be a 4 inch diameter. They are the same height as a #10 can, and again you can then use 4 inch diameter HVAC connectors. This could be used for the center pipe for anyone who doesn't happen to have some nice steel tubing lying around (raises hand - lol) of course it is thinner walled so it probably won't hold up as long, but it's cheap, easy and repeatable. On a side note, I have a rocket stove / pallet shack contraption that really needs to be seen to be fully understood...However I thought you might find my "foot warmer" box to be interesting. I used a 4"x10" register box (floor heater vent box) along with 4" HVAC couplings and 4" flexible aluminum dryer vent tubing. I built a 12"x30" wooden box out of 2x4's and 1/2" plywood. I used some corrugated plastic (old campaign signs) to line the bottom and sides (but not the top) of the inside of the box as "insulation" as well as added a couple of paper egg carton bottoms to the inside to mix the air - this will make sense in a minute. I cut two 4" holes with a hole saw on opposite corners of the top of the wooden box. I cut a "U" shape out the side of the register box (a picture is worth a thousand words right here) the box then sits upside down with the "U" shape cutout next to my rocket stove (my rocket stove is made from 1/4" wall, 6" diameter steel tubing that I had made by a welding shop) and is connected to a 2 foot section of 4" HVAC tubing which I used some copper wire to strap it to the riser of my stove and then is connected to the flexible dryer vent tubing and that goes back down to the wooden box and connects to one of the holes. At the other hole I have another section of 4" diameter cardboard shipping tube (got this free from where I used to work - PVC or HVAC tubing could also be used instead if needed) Which is a little taller than the section of HVAC connected to the stove. So.... the hot (fresh not exhaust) air from the bottom of the stove gets pulled into the bottom of the register box and because hot air rises, travels up the tube and is then forced back down into the wooden box, travels through the box across the air mixing egg cartons and then warms the non insulated top of the box.....where I put my feet 8^D.... and then out the other end and up the taller tube which acts like a siphon to help pull more hot air from the stove - again, because as I know you know, heat rises. Sorry for the long post but I thought it would be something you might be interested in trying. Cheers! P.S. - forgot to mention I used some heavy aluminum foil and more thin copper wire to "loosely" wrap the flexible dryer vent tubing - creating a somewhat insulating air gap around it. I'm sure there is a better method for that - but like you, I used what I had on hand lol.
Thanks for the excellent detailed info here. I scanned, but need to come back and spend some time reading this carefully. Nothing condescending or oafish about it though. Most oafs won't do "IMHO." :-) Thanks for the feedback. Thanks for watching. Now get back to warming your toes...or maybe you've been doing that all along.
Like always I enjoy watching your new creative ways and more affordable rocket for sharing with all of us! This looks really sharp painted black and so shiny 👍
Quick question/video idea. What are the golden rules when making a rocket stove? Things that cant be changed between designs? I know you have mentioned your intake hole being the same size as your chimeny. But could the internaks be wider/thinner or cone shaped? Do you need only one big intake or could you do smaller multiples as long as the sum space is the same? Other rules for rocket stoves I may have missed? Attempted a few and while Im learning would be good to 'stand on the shoulders of giants' as it were
I made my rocket stove from an empty 6kg fire extinguisher and a brake disk. Works very well and keeps my feet warm while i sit at it, waiting for my 10l water pot to boil.
@@GreenShortzDIY The brake disk is just a base welded to the bottom of the extinguisher. Actually it is the coolest part of the thing and most of the IR radiation comes from the lowest third of the extinguisher pipe, where the fire is burning. It gets visibly red hot if i throw some dry birch in it. :D I had to drill extra air holes at 1/3rd and 2/3rds lines to get it full combust. Boils 10 liters from ~4C to 100C in ~40 minutes, 10 minutes faster than our electric stove. Which is awesome since our cabin lot produces more wood than we can consume in a year. Free green energy!
That's great. I'd lice to be able to bring this setup camping . How could I make it stable enough to support a 5 quart dutch oven without risking toppling if it gets a slight bump? That's a perfect fire. Be great too when open fires are prohibited. Very nice
Thank you. I think you might want to brace it with several large rocks or hammer a length of rebar into the ground and wire the riser to it, to be safe with a big Dutch oven. I need to fire this guy up again. It was a good one. Thank you for watching.
Would love to see your take on a few efficiency additions: 1) secondary o2 mixer (fresh air intake about 1/3 up your riser) with control valve to perform a secondary burn of the wood gas 2) damper control (improvements to the sheet metal cover, essentially creating a door) 3) wrap copper lines around standpipe prior to inserting and filling (essentially merging the objectives of your last build into a multi tasker)
Good stuff here, Darian. Thank you for the input. I'm planning to build a rocket mass heater soon and will likely use this assembly (or a three-can one) as the riser. Also plan to do a proper rocket stove, with all the features, so secondary air and dampening will be a nice addition to that. Thanks for the suggestions. Thanks for watching.
Hi, Darian, you've brought up some interesting concepts. Re: your 1), above-- I always thought the purpose and design of a rocket stove was to suck in enough air to perform that secondary burn of the wood gas without additional o2 mixers/dampers? Have I missed something? My concern is: I just cast a stove in cement a couple of weeks ago, and it's not cured enough to fire it up, yet. so I won't know how it does for a bit. Thing is, casting a cement thing with an additional damper would make for a hugely complicated mold! I was really hoping this thing would burn all the fuel(s) efficiently enough as built... I totally see your point, though, and I love it as much as I hate it! I mean: I love maximizing efficiency, but I hate un-doing (or re-doing) something I've already done. I can't poke a hole in the concrete already set... ...And I've already cast another stove (in a slightly different configuration), and I really don't relish the idea of making a third one. With another hole in it. And I have no metal-working tools. And I don't have enough money to pay attention, let alone buy anything. So, yeah, I hate that. Any suggestions? Would sincerely love to hear any input (that only costs a nickel), you might have. Man, I hope I didn't waste my time (and the approx. $20.00 I spent on all this) on something that won't really work. I just want to heat my little garden shed/workshop with scrap wood and twigs. And I don't want it complicated (and it can't be expensive).
@@shaddec55 Bud, I think no matter HOW your rig burns, it would not be a waste. Remember, we all rely on each others past attempts to learn and grow as a community. The secondary line is a concept that some advanced builds I've seen use. It is more of an enhancement to efficiency than a requirement. It can certainly be frustrating to hear a great idea, one cement casting too late to implement, but that does not diminish the research and efforts already placed. The project I have in mind is all about efficiency and control. The way I've had it explained to me, the secondary air intake rapidly heats the air as it flows uncombusted through the burn chamber and just starts up the riser, where any residual gasses, (including the original air) mix with the super heated fresh o2, and the process is enhanced. Adding a flame vortex in the riser is another enhancement that is by no means necessary, but adds an efficiency boost. It all depends on the time and effort you want to spend on prototyping... and often failing. Let us know how your build turns out dude!
Wow, Darian, thank you so much for your encouraging response to my "panic" attack! LOL, I was indeed thinking I was "one cement casting too late to implement" what I thought was now a necessity. As you may know, preparing a cement mold is no short, easy task. Finally mixing and pouring the cement is a quick but satisfying pay-off for all the prior work. De-molding is the second little triumph when the thing doesn't crumble. All sweet... That said, I'm kind of working on a heat accumulator for the top of the "Franken stove", to be built out of sheet metal ventilation parts and potter's clay (read: so far, pencil and scratch pad). I don't begin to have enough room for a rocket mass heater in any of the configurations I've found in videos. (My shed is 12' X 12', one side is my workshop, the other side has lawnmower and other yard tools, etc. The foot-print of this thing needs to be ~2-3 sq. feet. There is no floor space for a mass accumulator.) Do you think I could incorporate that secondary burn o2 vent between the top of the concrete beast and the "accumulator" contraption? Would dearly love to hear your thoughts on this! I'm so very glad that I have found a "community" of like-minded individuals who are willing to share ideas and-- especially!-- encouragement. That absolutely means the world to me. I'm retired, fixed income, don't have money to "burn" (possibly intended pun...). Again, thank you so much for your heartening encouragement and your very concise description of possible enhancements-- yes: those have got some of my creaky old cogs turning anew!). And, YES! I will absolutely share however this beast performs-- good, bad, ugly or warped. Rock on!
I enjoyed the video. Thanks. I'm curious as to the efficacy of this unit for cooking. It makes an awesome fire torch, but I wonder about the ability to cook with this concept. Or, is it meant solely for boiling liquids.
Hi Larry. Boiling water is the best option, because it will soak up the heat. I have made a heat sink grill (no fire gets through) and cook with a wok. Both of those options work pretty well. I have also used a cast iron skillet to do grill cheese and scrambled eggs, but on a smaller rocket stove. Thank you for watching.
Hello UK! Thanks for the feedback. And you are correct, rocket stoves can be addictive. I have always loved fire. Thanks for watching and for the kudos.
@@GreenShortzDIY what intrigues me regarding this piece of ingenuity is the use of pearlite in its "as is" state. I had no idea it could be packed solo as an insulating wall.. I've been eyeballing it with hardwall plaster & sand. Must try this method on a paint can barbeque set up.its like a mini rocket stove. 👍🏻 Enjoy your weekend Mr Green. :)
Hi Lloyd. I just got a laser thermometer so now I can check. My steel rocket stove was running at about 850 degrees F. I haven't been able to get a rocket stove to melt aluminum in a crucible. But, I've only tried once. Thanks for watching.
As well insulated as this rocket stove is, I think it will get very hot and may approach the melting point of steel. I'd like to hear if this happens. Enjoyed the video, especially the fire!
Great video Tom, would plan kitty litter work as the filler medium? Love the easy ones 👍 might be time for a rocket build while my youngest daughter is visiting, she loves playing with fire also..
That’s a great idea. I need to study up first though. I’ve seen a few videos on it, but have never attempted it myself. Thanks for the suggestion. Thanks for watching.
@@GreenShortzDIY You may have already watched these; but, just in case you (or others reading this) haven't: ** NEW HD ** Making Sodium Silicate Quick, Cheap, Easy to Make, Super Simple & Highly Concentrated: th-cam.com/video/n_Kxm-w_XkI/w-d-xo.html (A great video; but, I wish he'd been wearing gloves!) Make Sodium Silicate (AKA "Water Glass") from Cat Litter and Drain Opener: th-cam.com/video/Ip-jDuM25FE/w-d-xo.html (A bit "technical;" but, still very understandable and useful...) I got my sodium Hydroxide from Ace hardware; and, it was in the ball park of $5 for a pound. I got my silica gel cat litter from WalMart. I don't remember what I paid for it; but, I'd have gotten a better price if they'd had the larger bag in stock at the time...
Appreciate the G'DAY, and here is just a thought, seeing as it is all made out of recycled materials (except for the perlite/concrete/aircrete or whatever anyone uses) how about you try the following: 2 regular paint cans + 3 of those small ones (the 1 ltr or 1 kg or whatever the hell is on them in any part of the world). Do the hole in the side of the bottom paint can as you mentioned, the rest is as you did, just using the smaller cans for the chimney pipe and leave the handle on the top outer can (easy to carry around when cleaning the back yard). Just a "world shattering" idea after watching the vid. Thanks for the ideas, appreciate it. Cheers.
The pavers are very porous and suck up a lot of heat before the stove really gets going, in my experience. A piece of fireplace rope or ceramic fiber would seal the riser to the pavers and help that manifold to function a little better.
Hi Tommy. In a rocket mass heater the chimney is capped with a barrel, diverting it down to a lower chimney exit and through a mass to capture the heat. In this rocket stove application, I’ll put a pot of water on the top to capture the heat of the flames. I do plan to make a rocket mass heater though. Thanks for watching.
Wow, I didn't know perlite was heat-resistant enough to use as an insulation (but, then again, I pretty much know nothing about perlite!) I guess I need to get intimate with Google and really check this stuff out.... I know it's light, and mixed in sufficient quantities with anything will fill a lot of space and reduce the weight of a unit of volume of whatever it's mixed with-- which I should have done in the molding of my very first attempt at creating a rocket stove-- which I made out of concrete in a Lowe's bucket, following one of your videos' instructions... Well, ALMOST following your instructions. I diverged in some critical ways, and... well... there were unintended consequences: First, instead of corrugated cardboard (such as pizza boxes), I used twelve-pack boxes (which is essentially card-stock) to line my bucket. This added some further volume of concrete (may not seem like a lot at first, but this gets worse...) Second, I used a 3" PVC pipe instead of 4" like you used, adding yet more volume of concrete (AND-- I used that card-stock to line the pipe, adding some volume of concrete). Last, I used two 2x4s screwed together instead of a 1/2 gallon container (also lined with card-stock) for the fire-box opening. Which (need I say?), added quite a bit more volume of concrete. Predictably (though I apparently didn't get that memo from the tiny part of me that THINKS on occasion), this beast weighs a ton and was most un-fun de-molding it after two days' cure time. That card-stock didn't hold much moisture for very long-- so I pretty much de-molded it right before it all dried out! It's been curing in the waning (almost Winter) sun for 9 or 10 days now. As the concrete lightens from a dark gray to something resembling cement-white, it seems to have lost a few micro-grams of weight, as well. I can kind of move it around a bit without herniating anything too terribly. I'll wait a full 30 days for this beast to cure before I attempt any fire in it (I've read that un-cured concrete is apt to explode when exposed to high heat-- safety first!) In the meantime... I'll make a mirror-image mold of a much shorter Lowe's bucket fire-box thing to use as a base for the Frankenstein rocket stove. I'll put a grate between the two parts. Wish me luck!
Franken-stove is curing pretty nicely. I made a base for it last week using the top part of another Lowe's bucket so it would match up. It's just now starting to cure. I really can't wait to fire this up! I"ll wait another week to try it out... Meantime, I made ANOTHER Franken-stove-- this time using a cat litter bucket (you know: those big yellow rectangle buckets that have 35 lbs of cat litter in them). I thought it would make an interesting shape. PLUS, I added lots of little cardboard cut-outs to it to (hopefully) give it a "Castle" look. Just poured the concrete in it yesterday. We'll see how it looks in a couple of days... Your videos gave me the inspiration to try all this-- thank you!
Your after making the concrete turn to dust inside that flask or what ever you want to call the inner outer casing . To much heat turns concrete to dust hence why plasterers wet down walls before applying the sand and cement coat .
Ha. True. Rocket stoves come in many shapes and sizes. This one is not for the rucksack. Although it is more portable than my concrete ones. :-) Thanks for watching.
"Rocket" refers to the the principle; and, is derived from the sound these things make when burning properly. Some are small enough to fit in a rucksack; others, you'd need a vehicle to move them around. Then, there are Rocket Mass Heaters, which are pretty well "permanent fixtures..."
@@NTF-zb9wi I was hoping to see how long they burned for. Or alternatly how much time did you ned to spend shoving little twigs into them. Say to boil a couple of Litres of Water and then how would one simmer? If you wanted it for keeping warm then a straight forward (heavy) metal chimney floo of a decent height would work. I have just thought that "V1" stove would be an apt name.
James, I got 2 cups of water will 4 eggs in it to boil in about 5 mins...or thereabout. The stove needed minute by minute stoking with wood, but that is the kind of thing I enjoy. To simmer can be trickier, rocket stoves tend to be rocketing or not. :-) Simply reducing the size of the fire can provide a fairly reliable simmer. Thanks for watching.
I've seen all your videos, pretty good, but I still don't know your name because you say it so fast, all I get is a blur of a sound, so if you wouldn't mind unrocketing your name that would be good. You say it the same exact way every time, and I've played it over and over and just can't get it. So, what is your name please?
Hi Bill. what I’m saying is “It’s Tom from GreenShortz”. My last name is Mills. Sometimes I throw that in. :-) Thanks for watching. Thanks for the feedback.
😩. SIMPLE??!! IT AINT. It needs at least 3 years practice with that kit you use, to make it. IF there's any way to get sufficient dosh to buy it all. Could you now try *Really Simple* please. That is simple enough for a senior citizen, with a can opener, and maybe some metal snips.... I've made quite a successful stove with a bit of old flue pipe, insulated with rock wool wrapped around it...but the whole thing is held together with string. Not perfect.
Ha. I can’t argue what that. I do have a decent stash of tools. :-) I appreciate your challenge...I may accept. Thanks for the feedback. Thanks for watching.
@@GreenShortzDIY okay Mr GreenShortz! Wonderful if you can think of something! The rock wool wrap, is pretty good, my idea, no one else thought of that yet..but I think it needs a burn chamber..not just the pipe with burning wood in it, and a fire underneath. After that..what about a super easy HOT TUB! with coiled copper pipe for winter baths on the balcony. A big plastic container could be the tub, with plastic pipe connected to coiled copper pipe...perhaps you did that already and I missed it....THANK YOU! GENIUS!
Another set of bricks out front to lengthen the burn chamber before the flames go vertical would improve efficiency. Fire brick has less thermal mass, it won't absorb as much heat and should be insulated as well. the horizontal to vertical transition area is where proper mixing and combustion efficiency occur. A secondary air inlet might help, it might also hurt by cooling the combustion process. In all the stoves I've built I've always strove to see only heat waves exit the stack, no smoke and no flames means everything was combusted. These are fun to play with. Nice documentation of the build and initial firing.
Helpful Hint: Before using the perlite, soak it in water for about 24 hours. The cement won't absorb as much water out of it, and it's easier to mix and to form.
GREAT video, GREAT idea.
Great tip. That would help with the dust too. Thank you. Thanks for watching.
Ya missus still looking for her salad spoons.😁😁
Great buddy, thanks. Just wot I need for my shed... so cold and to drive the damp back out. 👍👍
Ha! Yup. :-) Good luck with your build. You should look at a rocket mass heater. It might be better for heating an interior space. Thanks for watching.
Rocket mass heaters are awesome! I’ve seen some with an exhaust “pool” bank that works well. Put a smaller one on castor wheels so you can move it around.
@@GreenShortzDIY
Cheers buddy. I certainly will do. 👍👍
Very nice rocket stove
Great, inexpensive, easy to build rocket stove Tom! Congrats on launching Patreon! I'm proud to be an inaugural member of the support team!!!
Thanks so much Greg! I appreciate the support. Thanks for watching.
My suggestion is on filling... it looks like it would be a lot easier if you put an old plastic bag and a rubber band over the top of the burner while you add the first layer of concrete and most,of the perlite. It would probably also help to fold some paperboard like the side a cereal box into a shape somewhere between a ramp and a funnel to help guide in the perlite also. Great build, thanks for sharing.
It might also be easier to epoxy the two cans together versus shaping and screwing brackets.
Ian, great suggestions! The cement an perlite filling was trickier than I thought it would be. I was moving fast by that point in the build and didn’t stop to think. :-) Thanks for the feedback.
Good idea. One concern I had firing the stove was pressure build up. As it was, steam from the moist cement was venting through the gap between the cans. I suppose I could epoxy sections of the connection, leaving room for air movement. Thanks for the feedback. Thanks for watching.
Hi Ian, I used your recommendation in this new paint can rocket stove build. Featured your comment too. th-cam.com/video/JwjoPQtJ8Y0/w-d-xo.html
Nicely done Tom! 😃👍🏻👊🏻
Thanks Fred, as always. 👊🏻👍🏻
Hey Tom,
One way to make the build a little simpler is as you said by using #10 cans. Obviously you used what you had on hand - paint cans. But if you use #10 cans they have no "lip" like paint cans and then you can use a 6 inch diameter HVAC (or stovepipe if your local Lowes/Home D. has them) connector (coupling) to put the two or more cans together instead of the metal bands and screws. You may still need to use a few screws to hold it together if you're planning on moving it around. You can also use tin snips (aviation shears) to cut out the hole in the bottom - easier (IMHO) than using the angle grinder.
An easy free source for #10 (1 gallon) cans is your local Mexican (and probably other) food restaurant. They usually get beans and or chiles in this size can. You can either raid they're dumpster after hours (my method), or you could probably just ask them if they have any on hand. Also this whole process can be done without lining the inside at all. Just using the #10 cans. A bit less efficient/stable sure, but if you have the wood on hand (I work in a cabinet shop so...) and aren't prone to knocking things over...it still works fine. You could make the pot stand out of a 2nd HVAC connector in the same manner as you did here.
There is also another can size (I don't know the number) that happens to be a 4 inch diameter. They are the same height as a #10 can, and again you can then use 4 inch diameter HVAC connectors. This could be used for the center pipe for anyone who doesn't happen to have some nice steel tubing lying around (raises hand - lol) of course it is thinner walled so it probably won't hold up as long, but it's cheap, easy and repeatable.
On a side note, I have a rocket stove / pallet shack contraption that really needs to be seen to be fully understood...However I thought you might find my "foot warmer" box to be interesting. I used a 4"x10" register box (floor heater vent box) along with 4" HVAC couplings and 4" flexible aluminum dryer vent tubing. I built a 12"x30" wooden box out of 2x4's and 1/2" plywood. I used some corrugated plastic (old campaign signs) to line the bottom and sides (but not the top) of the inside of the box as "insulation" as well as added a couple of paper egg carton bottoms to the inside to mix the air - this will make sense in a minute. I cut two 4" holes with a hole saw on opposite corners of the top of the wooden box.
I cut a "U" shape out the side of the register box (a picture is worth a thousand words right here) the box then sits upside down with the "U" shape cutout next to my rocket stove (my rocket stove is made from 1/4" wall, 6" diameter steel tubing that I had made by a welding shop) and is connected to a 2 foot section of 4" HVAC tubing which I used some copper wire to strap it to the riser of my stove and then is connected to the flexible dryer vent tubing and that goes back down to the wooden box and connects to one of the holes. At the other hole I have another section of 4" diameter cardboard shipping tube (got this free from where I used to work - PVC or HVAC tubing could also be used instead if needed) Which is a little taller than the section of HVAC connected to the stove.
So.... the hot (fresh not exhaust) air from the bottom of the stove gets pulled into the bottom of the register box and because hot air rises, travels up the tube and is then forced back down into the wooden box, travels through the box across the air mixing egg cartons and then warms the non insulated top of the box.....where I put my feet 8^D.... and then out the other end and up the taller tube which acts like a siphon to help pull more hot air from the stove - again, because as I know you know, heat rises. Sorry for the long post but I thought it would be something you might be interested in trying.
Cheers!
P.S. - forgot to mention I used some heavy aluminum foil and more thin copper wire to "loosely" wrap the flexible dryer vent tubing - creating a somewhat insulating air gap around it. I'm sure there is a better method for that - but like you, I used what I had on hand lol.
Thanks for the excellent detailed info here. I scanned, but need to come back and spend some time reading this carefully. Nothing condescending or oafish about it though. Most oafs won't do "IMHO." :-) Thanks for the feedback. Thanks for watching. Now get back to warming your toes...or maybe you've been doing that all along.
Like always I enjoy watching your new creative ways and more affordable rocket for sharing with all of us! This looks really sharp painted black and so shiny 👍
Thanks for watching Mae! :-)
Quick question/video idea.
What are the golden rules when making a rocket stove? Things that cant be changed between designs? I know you have mentioned your intake hole being the same size as your chimeny. But could the internaks be wider/thinner or cone shaped? Do you need only one big intake or could you do smaller multiples as long as the sum space is the same?
Other rules for rocket stoves I may have missed? Attempted a few and while Im learning would be good to 'stand on the shoulders of giants' as it were
I made my rocket stove from an empty 6kg fire extinguisher and a brake disk. Works very well and keeps my feet warm while i sit at it, waiting for my 10l water pot to boil.
Cool. I bet the brake disc soaks up some heat for the toes. :-) I’ll have to incorporate one in a build soon. Thanks for watching.
@@GreenShortzDIY The brake disk is just a base welded to the bottom of the extinguisher. Actually it is the coolest part of the thing and most of the IR radiation comes from the lowest third of the extinguisher pipe, where the fire is burning. It gets visibly red hot if i throw some dry birch in it. :D
I had to drill extra air holes at 1/3rd and 2/3rds lines to get it full combust. Boils 10 liters from ~4C to 100C in ~40 minutes, 10 minutes faster than our electric stove. Which is awesome since our cabin lot produces more wood than we can consume in a year. Free green energy!
That's great. I'd lice to be able to bring this setup camping . How could I make it stable enough to support a 5 quart dutch oven without risking toppling if it gets a slight bump?
That's a perfect fire. Be great too when open fires are prohibited. Very nice
Thank you. I think you might want to brace it with several large rocks or hammer a length of rebar into the ground and wire the riser to it, to be safe with a big Dutch oven. I need to fire this guy up again. It was a good one. Thank you for watching.
For folks who don't have grinders and steel pipe........ would large soup cans work for the riser?
I love it. I'm still trying to find one insolated K shaped rocket stove would love to see that one being made.
I'm thinking about doing a K shaped stove out of aircrete. Is that what you are looking for? Thanks for watching.
@@GreenShortzDIY no in metal insolated but just like all your other videos I would still love to see the aircrete one too 👍😁
You attached the second can before you put in the concrete base... ?
Would love to see your take on a few efficiency additions:
1) secondary o2 mixer (fresh air intake about 1/3 up your riser) with control valve to perform a secondary burn of the wood gas
2) damper control (improvements to the sheet metal cover, essentially creating a door)
3) wrap copper lines around standpipe prior to inserting and filling (essentially merging the objectives of your last build into a multi tasker)
Good stuff here, Darian. Thank you for the input. I'm planning to build a rocket mass heater soon and will likely use this assembly (or a three-can one) as the riser. Also plan to do a proper rocket stove, with all the features, so secondary air and dampening will be a nice addition to that. Thanks for the suggestions. Thanks for watching.
Hi, Darian, you've brought up some interesting concepts. Re: your 1), above--
I always thought the purpose and design of a rocket stove was to suck in enough air to perform that secondary burn of the wood gas without additional o2 mixers/dampers? Have I missed something?
My concern is: I just cast a stove in cement a couple of weeks ago, and it's not cured enough to fire it up, yet. so I won't know how it does for a bit. Thing is, casting a cement thing with an additional damper would make for a hugely complicated mold! I was really hoping this thing would burn all the fuel(s) efficiently enough as built...
I totally see your point, though, and I love it as much as I hate it! I mean: I love maximizing efficiency, but I hate un-doing (or re-doing) something I've already done. I can't poke a hole in the concrete already set...
...And I've already cast another stove (in a slightly different configuration), and I really don't relish the idea of making a third one. With another hole in it. And I have no metal-working tools. And I don't have enough money to pay attention, let alone buy anything.
So, yeah, I hate that.
Any suggestions? Would sincerely love to hear any input (that only costs a nickel), you might have.
Man, I hope I didn't waste my time (and the approx. $20.00 I spent on all this) on something that won't really work. I just want to heat my little garden shed/workshop with scrap wood and twigs. And I don't want it complicated (and it can't be expensive).
@@shaddec55 Bud, I think no matter HOW your rig burns, it would not be a waste.
Remember, we all rely on each others past attempts to learn and grow as a community.
The secondary line is a concept that some advanced builds I've seen use. It is more of an enhancement to efficiency than a requirement. It can certainly be frustrating to hear a great idea, one cement casting too late to implement, but that does not diminish the research and efforts already placed.
The project I have in mind is all about efficiency and control. The way I've had it explained to me, the secondary air intake rapidly heats the air as it flows uncombusted through the burn chamber and just starts up the riser, where any residual gasses, (including the original air) mix with the super heated fresh o2, and the process is enhanced.
Adding a flame vortex in the riser is another enhancement that is by no means necessary, but adds an efficiency boost. It all depends on the time and effort you want to spend on prototyping... and often failing.
Let us know how your build turns out dude!
Wow, Darian, thank you so much for your encouraging response to my "panic" attack! LOL, I was indeed thinking I was "one cement casting too late to implement" what I thought was now a necessity. As you may know, preparing a cement mold is no short, easy task. Finally mixing and pouring the cement is a quick but satisfying pay-off for all the prior work. De-molding is the second little triumph when the thing doesn't crumble. All sweet...
That said, I'm kind of working on a heat accumulator for the top of the "Franken stove", to be built out of sheet metal ventilation parts and potter's clay (read: so far, pencil and scratch pad). I don't begin to have enough room for a rocket mass heater in any of the configurations I've found in videos. (My shed is 12' X 12', one side is my workshop, the other side has lawnmower and other yard tools, etc. The foot-print of this thing needs to be ~2-3 sq. feet. There is no floor space for a mass accumulator.)
Do you think I could incorporate that secondary burn o2 vent between the top of the concrete beast and the "accumulator" contraption? Would dearly love to hear your thoughts on this!
I'm so very glad that I have found a "community" of like-minded individuals who are willing to share ideas and-- especially!-- encouragement. That absolutely means the world to me. I'm retired, fixed income, don't have money to "burn" (possibly intended pun...).
Again, thank you so much for your heartening encouragement and your very concise description of possible enhancements-- yes: those have got some of my creaky old cogs turning anew!).
And, YES! I will absolutely share however this beast performs-- good, bad, ugly or warped.
Rock on!
Is the cement necessary, would some rocks do at the bottom to weigh it and then just pack it with perlite? Thanks brother, awesome ideas
I enjoyed the video. Thanks. I'm curious as to the efficacy of this unit for cooking. It makes an awesome fire torch, but I wonder about the ability to cook with this concept. Or, is it meant solely for boiling liquids.
Hi Larry. Boiling water is the best option, because it will soak up the heat. I have made a heat sink grill (no fire gets through) and cook with a wok. Both of those options work pretty well. I have also used a cast iron skillet to do grill cheese and scrambled eggs, but on a smaller rocket stove. Thank you for watching.
Great build! If you don't want to use perlite, wood ashes make excellent insulating material.
Thanks for the suggestion. Thanks for watching.
New subscriber. Loving your work.
Rocket stoves are pretty addictive once you build your first. 😁👌🏻
UK here. Pleased to greet you. :)
Hello UK! Thanks for the feedback. And you are correct, rocket stoves can be addictive. I have always loved fire. Thanks for watching and for the kudos.
@@GreenShortzDIY what intrigues me regarding this piece of ingenuity is the use of pearlite in its "as is" state.
I had no idea it could be packed solo as an insulating wall.. I've been eyeballing it with hardwall plaster & sand.
Must try this method on a paint can barbeque set up.its like a mini rocket stove. 👍🏻 Enjoy your weekend Mr Green. :)
Im going to try this, buy for now I ordered a Battlbox hellfire rocket stove, it's not arrived yet but im hoping it's a good one
can any of the rocket stoves be used as a forge. do you know how hot they burn? thankyou awesome videos
Hi Lloyd. I just got a laser thermometer so now I can check. My steel rocket stove was running at about 850 degrees F. I haven't been able to get a rocket stove to melt aluminum in a crucible. But, I've only tried once. Thanks for watching.
As well insulated as this rocket stove is, I think it will get very hot and may approach the melting point of steel. I'd like to hear if this happens. Enjoyed the video, especially the fire!
Hi Steven. I had the riser pipe glowing red when I burned the stove yesterday. No melting yet. Thanks for watching.
Great video Tom, would plan kitty litter work as the filler medium? Love the easy ones 👍 might be time for a rocket build while my youngest daughter is visiting, she loves playing with fire also..
Thanks Richard. I bet kitty litter would work fine. Sounds like a fun project with your daughter. Thanks for watching.
What is the proportion of perlite to cement
Have you considered making up some water glass to "paint" the pavers, to increase their heat tolerance?
That’s a great idea. I need to study up first though. I’ve seen a few videos on it, but have never attempted it myself. Thanks for the suggestion. Thanks for watching.
@@GreenShortzDIY You may have already watched these; but, just in case you (or others reading this) haven't:
** NEW HD ** Making Sodium Silicate Quick, Cheap, Easy to Make, Super Simple & Highly Concentrated:
th-cam.com/video/n_Kxm-w_XkI/w-d-xo.html (A great video; but, I wish he'd been wearing gloves!)
Make Sodium Silicate (AKA "Water Glass") from Cat Litter and Drain Opener:
th-cam.com/video/Ip-jDuM25FE/w-d-xo.html (A bit "technical;" but, still very understandable and useful...)
I got my sodium Hydroxide from Ace hardware; and, it was in the ball park of $5 for a pound. I got my silica gel cat litter from WalMart. I don't remember what I paid for it; but, I'd have gotten a better price if they'd had the larger bag in stock at the time...
Appreciate the G'DAY, and here is just a thought, seeing as it is all made out of recycled materials (except for the perlite/concrete/aircrete or whatever anyone uses) how about you try the following:
2 regular paint cans + 3 of those small ones (the 1 ltr or 1 kg or whatever the hell is on them in any part of the world).
Do the hole in the side of the bottom paint can as you mentioned, the rest is as you did, just using the smaller cans for the chimney pipe and leave the handle on the top outer can (easy to carry around when cleaning the back yard).
Just a "world shattering" idea after watching the vid.
Thanks for the ideas, appreciate it.
Cheers.
Bellows - haha this one is your best thus far - goes like a rocket
The pavers are very porous and suck up a lot of heat before the stove really gets going, in my experience. A piece of fireplace rope or ceramic fiber would seal the riser to the pavers and help that manifold to function a little better.
Do you have to cover the fenished stove in order to retain the heat? I see flame going straight up.
Hi Tommy. In a rocket mass heater the chimney is capped with a barrel, diverting it down to a lower chimney exit and through a mass to capture the heat. In this rocket stove application, I’ll put a pot of water on the top to capture the heat of the flames. I do plan to make a rocket mass heater though. Thanks for watching.
Rocket stoves are typically for cooking and uncovered. It's rocket mass heaters which are covered, directing the heat downward into the mass.
Wow, I didn't know perlite was heat-resistant enough to use as an insulation (but, then again, I pretty much know nothing about perlite!) I guess I need to get intimate with Google and really check this stuff out....
I know it's light, and mixed in sufficient quantities with anything will fill a lot of space and reduce the weight of a unit of volume of whatever it's mixed with-- which I should have done in the molding of my very first attempt at creating a rocket stove-- which I made out of concrete in a Lowe's bucket, following one of your videos' instructions...
Well, ALMOST following your instructions. I diverged in some critical ways, and... well... there were unintended consequences:
First, instead of corrugated cardboard (such as pizza boxes), I used twelve-pack boxes (which is essentially card-stock) to line my bucket. This added some further volume of concrete (may not seem like a lot at first, but this gets worse...)
Second, I used a 3" PVC pipe instead of 4" like you used, adding yet more volume of concrete (AND-- I used that card-stock to line the pipe, adding some volume of concrete).
Last, I used two 2x4s screwed together instead of a 1/2 gallon container (also lined with card-stock) for the fire-box opening. Which (need I say?), added quite a bit more volume of concrete.
Predictably (though I apparently didn't get that memo from the tiny part of me that THINKS on occasion), this beast weighs a ton and was most un-fun de-molding it after two days' cure time. That card-stock didn't hold much moisture for very long-- so I pretty much de-molded it right before it all dried out!
It's been curing in the waning (almost Winter) sun for 9 or 10 days now. As the concrete lightens from a dark gray to something resembling cement-white, it seems to have lost a few micro-grams of weight, as well. I can kind of move it around a bit without herniating anything too terribly.
I'll wait a full 30 days for this beast to cure before I attempt any fire in it (I've read that un-cured concrete is apt to explode when exposed to high heat-- safety first!) In the meantime...
I'll make a mirror-image mold of a much shorter Lowe's bucket fire-box thing to use as a base for the Frankenstein rocket stove. I'll put a grate between the two parts.
Wish me luck!
Shadecc, your build sounds excellent. Would love to hear how Franken-stove does once you fire it up. Thanks for the comment. Thanks for watching.
Franken-stove is curing pretty nicely. I made a base for it last week using the top part of another Lowe's bucket so it would match up. It's just now starting to cure. I really can't wait to fire this up! I"ll wait another week to try it out...
Meantime, I made ANOTHER Franken-stove-- this time using a cat litter bucket (you know: those big yellow rectangle buckets that have 35 lbs of cat litter in them). I thought it would make an interesting shape. PLUS, I added lots of little cardboard cut-outs to it to (hopefully) give it a "Castle" look. Just poured the concrete in it yesterday. We'll see how it looks in a couple of days...
Your videos gave me the inspiration to try all this-- thank you!
that's awesome!
Thanks for watching, Chris.
Great vid! subscribed :p
Concrete does not "dry", it CURES!
I always say it wrong. :-) Thanks for watching.
I like to see rocket stove
Your after making the concrete turn to dust inside that flask or what ever you want to call the inner outer casing . To much heat turns concrete to dust hence why plasterers wet down walls before applying the sand and cement coat .
Thank you for the feedback. Thank you for watching.
how to make a paint can and perlite rocket stove salam sukses
❤❤❤
Thank you for watching.
👍👍👍
could have started with just one paint can, then put the top can on once you've filled the bottom can
Thanks for the suggestion, Russ. Thanks for watching.
Forgive me but I thought the Rocket Stove was a Backwoodsman thing. This is going to be awful heavy in the Rucksack.
Ha. True. Rocket stoves come in many shapes and sizes. This one is not for the rucksack. Although it is more portable than my concrete ones. :-) Thanks for watching.
"Rocket" refers to the the principle; and, is derived from the sound these things make when burning properly. Some are small enough to fit in a rucksack; others, you'd need a vehicle to move them around. Then, there are Rocket Mass Heaters, which are pretty well "permanent fixtures..."
@@NTF-zb9wi I was hoping to see how long they burned for. Or alternatly how much time did you ned to spend shoving little twigs into them. Say to boil a couple of Litres of Water and then how would one simmer? If you wanted it for keeping warm then a straight forward (heavy) metal chimney floo of a decent height would work. I have just thought that "V1" stove would be an apt name.
James, I got 2 cups of water will 4 eggs in it to boil in about 5 mins...or thereabout. The stove needed minute by minute stoking with wood, but that is the kind of thing I enjoy. To simmer can be trickier, rocket stoves tend to be rocketing or not. :-) Simply reducing the size of the fire can provide a fairly reliable simmer. Thanks for watching.
I've seen all your videos, pretty good, but I still don't know your name because you say it so fast, all I get is a blur of a sound, so if you wouldn't mind unrocketing your name that would be good. You say it the same exact way every time, and I've played it over and over and just can't get it. So, what is your name please?
Hi Bill. what I’m saying is “It’s Tom from GreenShortz”. My last name is Mills. Sometimes I throw that in. :-) Thanks for watching. Thanks for the feedback.
That really sucks! 😉. You barely had any fire 🔥 and it was still sucking the smoke up the chimney! Must be a very effective design.
I had to read your comment twice, to know if was a complement. :-) Thanks for watching.
First
Yay! Thanks for watching. :-)
Try making your own claw bricks. It's not hard.
ทำไห้อันตืคับ
ขอขอบคุณ. ขอบคุณที่รับชม. พี่ชายของฉันอาศัยอยู่ในกรุงเทพ ฉันรักประเทศไทย ดินแดนแห่งรอยยิ้ม :-)
😩. SIMPLE??!! IT AINT. It needs at least 3 years practice with that kit you use, to make it. IF there's any way to get sufficient dosh to buy it all. Could you now try *Really Simple* please. That is simple enough for a senior citizen, with a can opener, and maybe some metal snips.... I've made quite a successful stove with a bit of old flue pipe, insulated with rock wool wrapped around it...but the whole thing is held together with string. Not perfect.
Ha. I can’t argue what that. I do have a decent stash of tools. :-) I appreciate your challenge...I may accept. Thanks for the feedback. Thanks for watching.
@@GreenShortzDIY okay Mr GreenShortz! Wonderful if you can think of something! The rock wool wrap, is pretty good, my idea, no one else thought of that yet..but I think it needs a burn chamber..not just the pipe with burning wood in it, and a fire underneath. After that..what about a super easy HOT TUB! with coiled copper pipe for winter baths on the balcony. A big plastic container could be the tub, with plastic pipe connected to coiled copper pipe...perhaps you did that already and I missed it....THANK YOU! GENIUS!
Hi Jeanette. I made a video for you. th-cam.com/video/JwjoPQtJ8Y0/w-d-xo.html Let me know how I did. Thanks for the feedback. :-)