1752 Stop The Press - The Liberator Is Here - The Stove To End All Stoves! 

You non-stop enthusiasm combined with your knowledge is always entertaining and enlightening.👍

Hi Robert, these guys are in Bourbon Missouri and a lot of us have put dampers on the intake air to slow the burn for pellet heating. Otherwise, the unit is a blast furnace and will cook you out of your own house. Adding a thermal mass is indeed the most efficient use of this heater if you can afford the space for the mass. I have been to the factory and the fellows that work there are genuinely ingenious.

When a man laughs while saying "I'm very reluctant to take an angle grinder to it" I'm all in 😂👌

Your shouty voice and crazy laughing are one of the most endearing I have heard. You remind me of my late engineering profs who was just about the best teacher I ever had. Keep going- its wonderful

I've had the older model Liberator for a few years now running mostly pellets. It does exactly as advertised. Heats up very quick, burns hot and efficiently. I have nothing negative to say about it.

Hello Robert! We're glad to see the heater found its way to you. If there is anything else we can help you with, please feel free to let us know. We may or may not be developing a stirling engine for these heaters in the future. And dont feel bad about taking a grinder to it. We will have a 3rd generation heater coming out in the future, and we'll be sure to send one your way. I can't give away too much, but its going to be absolutely nuts!

This is the basis for a rocket stove mass heater. The exhaust would be piped through a long horizontal pipe embedded in a thick piece of masonry inside the home. Then to the outside into a fairly tall chimney pipe. When done correctly it produces no smoke at all. People often use the inside masonry, with cushions of course, as a couch.

Improvement suggestions. Instead of drilling extra holes, run a tube from the front to the back. The air will also be heated by the combustion part. Improve heat convection by increasing the surface by welding on extra pipes or flanges on the outside.

You really have a way of imparting knowledge and enthusiasm at the same time, whish I had you as my teacher when I was growing up.

For those of us who are ladies having a trivet on the top of the lid to be able to put a dutch oven on to cook. Also maybe make accessories such as a off-grid food dehydrator that can go on the trivet, reflector for the back that could be far enough away from the back that there would be a shelf to put a bread loaf pan and possibly bake bread or meatloaf. The reflector shield would have to have a hinge to openba side to put in and take out the liaf pan. Lol Yes, I am a female and a foodie. Lol Women love accessories that can be purchased with or after.

In Ukrainian villages, they build massive rocket-style stoves/ovens, which take up a good chunk of the wall. I think people even sleep on the very top of it, as it stays warm all night. For the country people, the oven/stove isn't just an appliance, it's a viable part of the home to dry wet clothes, to cook, to bake, to sleep on after the day is done. It's amazing how much thermal mass those things have...

So grateful for all you share with us. I am planning out three Rocket stoves, one for house, one for shop and one for my bus to tv conversion. Love all the ideas, plans and explanations. Have to check out the boys up north, awesome that we have folks here in the states. From AZ thank you kindly!

It's brilliant to see you get the respect from the wider community 👏. Keep making the world a better place mr Murray Smith

People are willing to pay for convenience and no one likes to spend time cleaning the rig day after day. So, one suggestion to expand on what you have, look at the bottom of the riser and burn chamber. In a drawing it looks like a rectangle connected with a circle on one end which I'll call the BASE. Change the mount system so that the entire BASE becomes a hatch which will swing open on the long side so all the ash will fall to the ground or in a larger container. Then you can easily sweep it clean with a broom if it's not hot 🔥. Close the BASE and your done, less than a minute! People like easy clean and are willing to pay for it! If you like my idea, give me a good price on your new build. :). GL!

Hi Bob. One improvement I can think of is a Sand Battery . One can make it as a buy on for the Liberator. Just a box that encapsulates the chimney, and the client can then fill it with sand... Or water and heat it....

the only way you lose the heat is venting exhaust gasses while they are still hot enough to capture and redirect to the heating location. the improvement like you mentioned could be an easy cleaning feature, also a coolant loop in the cavity space would be good to help with either heat storage, second room heat or domestic hot water use.

If your enthusiastic knowledge is combined with these manufacturers the i can only say that the sky is the limit in rocket stove technology from now on . Great video and a wealth of extremely helpful information as always. Thank you.

That is fantastic! I have watched this for years! Great to see your review!!

Would have been nice to see the Liberator lit up and working, and some results from the test. Maybe another video? Thank you though for doing such wonderfully informative videos.

Fantastic Rob, wonderful application of enthusiasm, knowledge and passion buddy, thanks for sharing

It would be adding more cost, but I think add two runners on the bottom that run the length of the base to the chimney for the secondary air intakes, and a flappy panel on a hinge could be used as a damper to control the amount of air intake

Birds eye view on the drum, put a full height half divider and in the front section you can fill it with sand. Will still act like a rocket stove giving instant heat but will also charge the sand as a battery!

Isn't the internet amazing! Someone on the other side of the planet who clearly has followed Robs journey with the rocket stove and recognises he knows what he is talking about. Now they are willing to send their stove over for him to assess and if possible improve. Love it!

You have to be careful with adding additional vents. You will run into back drafting issues.

I just found your channel yesterday. I wish you lived in my neighborhood. I would have a blast in your shop learning. The wisdom is so enjoyable!

So glad they sent you their heater to look over. Wonder if a sliding ash pan on the bottom would be hard to add to it?

An extra inlet, to take oxygen from the outside (of the house etc). The inlet may wrap around the outlet to preheat the air intake.

Wow nice one Liberator looks like a great product !!

The idea behind Insulating the Rocket Stove is not to do anything in the way of heat radiation. It's 2 purposes are to First get the burn box area up to temperature ASAP. Second is insulating the Inner wall is to Protect the steel from being destroyed by the excessive heat & keeping enough heat in the riser tube is to make sure the wood gas ignites before it leaves said tube. This is where the secondary air comes into play right at the vertical turn of the riser tube.

an option for a heat exchanger would be a nice addition so that you can get heated water on tap (or if you want to take it to extremes HPS for a small generator)

Looking forward to 1753 already. That's a lovely looking bit of kit!

Anxiously following this thread. Can't wait!!!

Wrap the heat exchanger with corrugated metal. You want more surface area to better couple the hot metal to the air. Look up heat exchangers for camp cooking to get an idea.

The ventilator holes shouldn't leak ash, since they are drawing air. But the easiest fix is just a short angled up tube on the outside. More on those holes, if you put one near each of the three available corners, they would add oxygen while starting the vortex. You don't need a lot to start that, just a hint (also keeps the temp from dropping), which three maybe 3/8 inch holes would do.

Interesting, I built a rocket stove the size of that large stove and it got the back of my pizza oven red hot! I couldn't believe it, I thought my BakerStone pizza oven was going to explode, the temperature dial went all the way around! I had to remove the pizza oven and it was OK. After that incident, I added a vent door to control the temperature and I can now keep it steady at 350F to bake bread etc. Very powerful those rocket stoves. I use the wood from falling branches at my Farm.

Hi, yes I can think of a few suggestions.. you covered two in your vid with a secondary air inlet and an ash pan.. but the only issue you need to ensure is that after the initial burn phase that no air will escape from where its not supposed to.. being as it is meant for internal use you don't want any form of carbon monoxide to leak.. My suggestion includes a secondary burn feed from the main air inlet (Shared inlet) this will negate any blowback if it were to occur as it would be dragged back in via the initial burn inlet. Ash extraction could be done by installing a service hatch on the side or bottom as you suggest, but this will need to be sealed using fire rope or caulking.. Air flow is like water and electricity, it always follows the path of least resistance, so although the heat is pumping out of the top of the rocket stove and hitting the top plate (which can suffer from heat damage over long term) most of the heat also flows down the side of the exhaust port. My suggestion would be to insert some baffle plates to force the air in circular motion around the radiant heater section before it gets to the exhaust port. Yes this might slow the air flow down a bit. But it would also make it more efficient in using the available heat produced to come into contact with the outer edge. Also on that note, utilising the available heat on the outer edge .. my biggest suggestion is to add fins to the internal and external surfaces of the radian heat drum.. this will give a larger surface area for heat transfer and also increase the rate at which the heat is dissipated out of the system.. Only problem is.. now I've made these suggestions on a public forum they cannot be used in a patent and are open to the public.. that sort of thing really sucks if your trying to make the ideas novel and unique.. to improve your own patent applications. Anyhow good luck to them on developing their product 😎 👍

Add an ash pan that seals the space effectively so that when you can adjust the amount of venting by sliding it in and out., that way you sort two issues with one simple alteration.

A very useful bit of explication there, with the phrasing of "burn at" vs "burn to." I've been discussing this with my family, and we hadn't hit upon that very clear conceptual framing. Thanks!

MT is Montana, MO is Missouri, just information, Love your channel, I’m the same way you are in improving things. Thanks

Thanks for looking into this and helping them to improve the Liberator.

You could use an access door at the bottom of the chimney side, that hinges out from the backside, for a clean out. If you just want airflow then cut some conduit straws to lay inside at the bottom. The conduit can be perforated or have perpindicular slits for airflow, and it will pull from the cold side. That way you aren't making holes in your chimney bottom.

if you fitted iron pipe(s) where the holes are drilled you could then use those pipes, when cold, to vacuum out the ash, the change would add little cost. You could also add fans to increase the flow. The neatest solution I have seen however was the Aussie rockets site where he created a vortex.

To allow the point for air entry and easy cleaning, try a 50x100mm (2x4inch) pipe under the bottom of the ‘J’, coming to the ‘front’ of the unit, with an removable ash drawer. The drawer can then also be opened and closed by varying amounts to regulate the air then entering the bottom of the flue. That way all three intakes (main air intake, fuel hopper and ‘bypass’ air intake with the ash collector drawer) are at the ‘front’ of the heater.

Great series on rocket stoves Bob. An improvement suggestion, a hot plate for cooking and boiling a kettle seems essential imo.

Instead of an ash pan, provide an ash hoe with which to reach in through the fire chamber & rake the ashes out. In order to introduce secondary oxygen to the vertical rocket tube, drill a 1" hole through the vertical fire tube about 5" up from the bottom & tap it for 1" pipe thread, drill a second hole through the outside barrel to correspond with the first, making it just large enough to slide a piece of threaded 1" black iron pipe through the outer barrel & screw it into the fire tube. At the end of the 1" pipe sticking out of the barrel, drill a series of holes (1/2" dia). 1" schedule 40 steel should have an inside diameter of 1.049 in., and the outside diameter of 3/4" sch 40 steel pipe should be about 1,050 in,. Take a short length of 3/4 " pipe and drill holes corresponding to those in the 1" pipe and then turn it on a lath until it just fits into the 1" pipe, & stop one end. To adjust the secondary air flow, rotate & slide the inner tube to expose more or fewer holes through the outer pipe.

I just really like you Robert, you seem so genuine. Keep up the good work.

I was worried we might never see another rocket stove video! I am thrilled you got in touch with the professionals... Actually, the other way around! It proves you know what you are talking about, and perhaps that is what others might be implementing to their projects! Cheers

Hi Robert, not my own idea, but seen in a video of something very similar - wood gasifiers - for vehicles, they added (or injected?) water or steam into the unit, which took care of ash/ soot/ creosote problems and hugely (+/- 40% ??) improved clean heat output. Overlapping technologies & sharing refinements seems like a good idea to me. Have fun! I think it was a you tube video which covered WW2 and included Germany, also London, amongst others, also later, showing more modern use of gasifiers mounted on the backs of pick-up trucks, which looked unusual, but still, a great, portable concept!

Suggest: change lid at top to inverted drum so you can get down to bottom for cleaning. Put outer sleeve (open at bottom and top) over gas chamber to create convection current, include fins b/w inner and outer walls for better heat exchange, which will remove more heat from exhaust gases, it will also keep the outer gas chamber temperature lower and safer

In the past I’ve worked on a vortex rocket stove which made the gravity fed flame concentrate into a swirl coming out from the stack which generate more heat while burning less fuel . The idea is to have the gravity fed material drop down into a circular burn chamber slanted slightly upward to the round stack while positioning the air intake at just the right placement to control the adjustable draft or air intake .Burnt material or ash from pellets would drop down through a grate into a collection box . When built right and depending on the controlling of the air intake , you will actually have a very strong swirl of flame which is very interesting to see .

1 minute 30 seconds in and I gotta hit the like button just for the humor ! Can’t wait to see any improvements.

I got excited before you even opened the box! 😂🤣😂🤣

MO is still Missouri. 😀 MT is Montana.

That looks very well put together. But if they're asking for ideas... 1) Another air channel beside or under the main intake to supply hot, fresh air to the flue/chimney 2) Crinkle the sides of the barrel to increase the surface area and radiative emissions. Some kind of wave pattern or 90 degree bends, like a washboard. It would use extra material for the same diameter, but that's kind of the point. 3) An option for running a coil of pipe through the barrel to heat water. Maybe just an access port on the top and bottom, with a pipe fitting of some standard size, would be useful enough to allow people to mod that themselves without taking an angle grinder to their beautiful stove. 4) A thermostat. Some kind of feedback loop for output temperature vs. intake air. I'm thinking the effluent temperature from #3 here, but perhaps there could be a design for the outside air temperature as well. I'm not sure how much you can throttle this thing down without affecting the burn quality, smoke, etc, but it seems like some kind of thermostat would be very useful. It might be possible with a bi-metallic strip, a lever to increase the travel distance, and a bicycle brake cable. The valve would need to be easy to move if you're relying purely on the mechanical force of the strip. A coil of something with a high coefficient of thermal expansion might also work.

Beautiful!

Jeez I love this channel! I can't wait to see what you do with the Liberator! From what I've already read in the comments, you're going to have plenty of ideas for improvement with this, can't wait!

This would pair very well with a Tesla Turbine from TesTur Energy. We've just run our first steam tests. Previously we've achieved 4 kW+ with just compressed air alone. In fact, at one point, we were working with Sky Huddleston of Liberator to apply for a grant to pursue pairing the two together, which didn't materialize.

I have had one myself in my other building, sold building with stove, worked GREAT, will buy another after new building built, was in Massachusetts, now in Tennessee.

I think it's great Rob, that someone with your noggin caliber is getting right into this. Thanks for explaining the finer points of effective burn temperature and the whole principle behind an effective rocket stove. The only thing that I can think of to modify this stove is to have a smaller version. Maybe one that could be dismantled ? But we dont want to sacrifice simplicity. The focus on these stoves is evolving and it will be very interesting to see where it goes. Some method of chimney insulation for the DIYer would be good.

My Dunsley Yorkshire stove could almost be described as a kind of rocket stove, it has a large fire box for logs, at the back and at the bottom of the chamber is a slot maybe 11/2" high, it is there where I have to light it. The firebox merely undergoes Pyrolysis, once the flames exit through the slot in the back they go through what would be best described has a venturi chamber, this is firebrick insulated and a special brick with I think about 8 holes in it which line up with holes in the back of the steel. The flames drag in more air, and the afterburn chamber goes to about 1500 degrees where it burns off all the smoke, this is then sent around a boiler jacket before heading for the chimney at the same time it passes over the top of the fire box fire brick which provides more heat for pyrolysis. It burns very clean provides hot water and central heating in the worst of winter, it has just not been cold enough yet to use it. But the design could be used in a rocket stove and you may be able to get a diagram online. Another thing I once read about was a professor hills boiler, these involve a down burn feed and a super insulated refractory channel with a air blower.

I can suggest a two chamber sliding ash tray. With one chamber in the stove under a grate to keep the wood above and let the ash fall down into the chamber. While the stove is still burning the sliding ash tray can be moved to place the empty chamber into the stove while the chamber that just slid out can be emptied of ash. The ash tray would just need to slide back and forth from left to right in order to empty one of the chambers. The stove never has to be shut down to empty the ash and no efficiency should be lost.

We actually exported something! Excellent review, on a very nice product. Thankyou.

Consider testing the air flow of the air intake holes you suggested adding to the Liberator stove by having the ability to control the amount of air entering. Looking forward to the results. Thanks for the video. (JF)

I love your knowledge and how you teach as you talk. Thank you for your content and insight.

1Up the sides of the larger tube - add a few heat exchanger tubes that go all the way through the main chamber, possibly large enough for an added 2. fan, or one of those wood stove fans that operate on heat from the stove. 3.Maybe add a spot of plate on top for warming up coffee or frying some eggs? 4.Paint it with some cool looking flames? 5.Make an an attachable tank and input tube for modification into a liquid fuel (veg/motor oil) stove? 6.Put radiator fins on the outside to help radiate the heat. 7. A modification to run a hose to and from a standard water heater, and water jacket heat exchanger to either replace or supplement home hot water heaters. 8. An add-on tool kit for cleaning/adjusting the unit. 9. A health and safety sticker... lol , ok I'm out of ideas... lol 🤣

Thank you, I really appreciate your work

Well done to the guys at Liberator. If Robert likes it, well what can I say?

I just hope everybody can stay warm this winter good luck❤️🇦🇺

Thanks Robert!

Here's my comment to boost the YT algorithm. Thanks for your willingness to share your knowledge; I really appreciate it.

@3:08 I think those fasteners securing the insulation will prove to be a design flaw. Those may corrode from hot exhaust gases. Also possibly cause the insulation to crack and fall apart due to expansion. I would suggest; instead of bolts, score a rough texture onto the steel walls, and secure the insulation with a thermosetting epoxy.

Dear Robert, please design and sell basic starter kits, with the option to modify and collaborate, using common plumbing fixtures to produce an efficient stove for any individual purpose...

I was waiting for you to spark it up and let it roar !!!! . I must have one in my life ! Liberator !

I like the round exterior housing, it looks like it would lend itself, quite easily to adding a water coil for hot water or distribute heat to other areas.

brilliant explanation, thanks

👍💜👍💜......love the community spirit ....👍

Thanks for sharing, always good to see innovation 👍

Before you modify the Liberator itself, see if you can make a waste oil kit for it that people who own Liberator's could buy and drop in without modification. ideally the waste oil kit would have an external "tank" that holds about 8hrs worth of oil and a way to see how much is in the "tank".

I also was going to suggest incorporating a sand battery into that but it looks like it's already been suggested. Great video thanks.

Brilliant Robert, great project. I've a vintage cast iron Tangye stove, it has horizontal, slightly inclined air ports right through the upper section of the stove body. This adds surface area and encourages air flow as cold air is drawn in at the lower end of the port and exits as hot air. Might be too much of a modification but it could be an optional model B Liberator. Tony

The humanitarian objective of keeping people warm, especially in cold worn torn countries where power stations are being bombed out at the moment would be staggering.

Depending on the application or combination thereof if they were to fill the heating chamber with sand but have hollow pipes running through it the sand would heat up and draw air from the bottom, through the pipes, and then out. It can capture the heat quickly and use natural convection currents to slowly (passively) radiate the heat.

Love your channel! ❤️

Very happy to have subscribed to your channel, thanks for sharing the knowledge 👍

Robert: Rather than an ash pan under the amplifier elbow where you have a row of holes drilled, try an angled slot ground into the elbow on a 45° angle where the bottom of this air intake slot is 30mm from the bottom, no ash will roll out here and the relocation of the intake of the air jet air intake will enhance the draw toward through and up the flue. Holes across the bottom will tend to create a burn there and not enhance the draw where it is needed. I would like to see this in oil burner with an automatic light system for a thermostat and flame sensor, etc. I also don't see a circulation blower on the hot air plenum, as a unit this size should have a better way to utilize flow to the space it is intended to heat. And for thoughts and giggles, I am starting a build of a soybean (aka rapeseed oil) forced air furnace to replace my wood burning stove because the price of cut wood deliveries has gone out of sight in my are, and I assume it has gone up drastically in most places.

Have a look in the horizontal burn chamber of the liberator and I think you will see insulation on the inside that is detachable and the burn chamber width is wider than the feed tube so the insulation doesn't obstruct the gravity feed.

The exhaust can be run under the floor and benches, then up and out. These things are awesome in their potential. From drying clothes to heating water through copper lines to a bathtub , hot tub, or sink

I've tinkered with homemade rocket stoves for a few years. Love the ideas on the different heater options they provide. From masonry heaters, rocket mass, and drop-in units like this and the "wiseway" pellet stove. Very cool. I love burning wood for heat. But my back is giving out so pellet is probably going to be my route. Great to hear someone else and their findings in this "hobby " your description on how the Temps can rise and improper over insulation.... spot on...

For the ash removal to the horizontal, the ceramic could be sat in it's own 'U' steel channel section that is removable.

I watched some videos on rocket stoves that used a long pipe connected to the stove that zig zagged from ceiling to floor placed next to a heat sink wall of stone or clay. This was done to use as much heat as possible in the home and not let the energy go to waste by venting it outside. After the heat from the pipe was spent, the pipe coiled back around the initial "heating drum" from the floor to heat up the air a little bit to help push what was used back outside since the air in the pipes had cooled and most of the energy was spent heating the home and/or heat sink. These folks channeled air from outside the house to feed a sealable chamber under the fire. I think the fire was on a grate of some kind. If the initial air for the fire in the lower chamber and air for the additional vents, like the holes made to help combust the gasified material, came from outside the house it may not be necessary to ventilate the home with a cracked window or whatever is used to ventilate the house. The air inside the home would only be warming the air inside and any gases that may cause harm wouldn't be able to enter the home and would return outside through whatever piping originally vents to the outside. The intake vents would need to be covered and away from the exhaust to keep from circulating non combustible air. I think much of this has already been done in small scale and in some homes. But I'm not sure that anyone has tried using air from outside the home to help combust the gasified material they are using for the rocket stove.

I would watch a channel of you just reviewing other people's work like this. It's like shark tank with a conscience.

Love this channel!!

Reasonable Technical explanation as well great suggestions ,thanks ROB.

Great VID !!, Burbon is in Missouri MO is Missouri. Montana is MT. Keep up the great Vids, I've been following your posts on this series and much as possible.

Have you considered whether to employ a venturi style air input which may replace the need for the air holes at the base of the stove? Just a thought. Keep up the good work Rob, always interesting and certainly beneficial for us off gridders.

Great one, waiting for the following one

It could be possible to extend the bottom square pipe and cover the open end with a hinged cover with air valve. This way you can easily clean out the whole pipe by pushing through a simple piece of wood into the ash bin underneath. A simple folded metal tray sliding on fixed bars could serve as low dust ash holder. On top of the extended pipe a cooking plate can be mounted.

Looks great, thanks for sharing.

Superb yes it is a thing of beauty, ive built one on the same principle but mines not as neat as the liberator, i like that ceramic lining inside flue very clever

Yeah, an air intake could improve its efficiency, but it seems pretty efficient already. For me, what that stove is missing is a water heater, using a copper coil wound around that internal chimney. A fairly simple plumbing job, with cold in/hot out, and maybe even a small hot water tank in there, though that would probably need some kind of pressure release valve. Seriously, with a constant feed hopper and hot water on tap, it would be a really useful piece of kit! Never mind replacing the AGA or Rayburn, you could build your own steam turbine generator or locomotive with a few of those!!!