My Clay/Sand Mortar Mix Recipe: 3 parts dry sharp sand by volume, 1 part dry ground fire clay by volume. Add water to desired consistency. Fire clay: amzn.to/2ykT2B0 Sharp sand: amzn.to/2LJKqa9
I would add best to use washed soft sand and the addition of Lime at one part in four of above mix will improve the mixes stability without effecting the mixtures ability to be recycled.
Matt, I see you heading on the right path, To be able to extract every calorie of energy, burning safely and cleanly both for the air and more importantly in a professionally presented and well run way, praise aside, Simple Quick and Affordable design that gives Speed Convince and Reliability daily.. its all there!
Hello sir! I recently built a batch box rocket with a heated bench (stratification) in my living room, inspired by both yourself and Peter vanderberg. Just wanted to say thanks for the info and inspiration 😊😊
Have you used a lime based mortar? This was the go to in victorian England for chimneys. So far I've found commercial refractory mortar to be lime, clay, sand and cement. As far as I could figure out the lime makes the mortar more water/steam resistant. I imagine that the heat cycles produce condensation inside the heater making the mortar ever slightly damp and therefore creating 'steam'. Steam expands, hence the cracks?
Thanks for the video Matt, great timing as tomorrow we start building our brick RMH using your designs. Very excited! Regarding more design ideas - I'd love to see your take on a rocket powered hot water tank. I've got an old electric immersion heater and thought it would be cool to recycle the insulated copper tank for a rocket project.
Great video. I realised from this what fire clay is. Got a bag and expected it to be more clay like. Cob also works abit the same i think. It helps bind the sand. And the sand stops cracking. Question Matt Do you use this mix in all areas and with all the stones. Or is it for internal? Do you have a video showing you mortoring bricks or can you point me to somewhere someone ?
Mat, I went to get some sand where I purchased my bricks and they told me I needed portland cement with their brand of fire clay. Also said any sand would do even sandbox sand, they said sand is sand just different coarseness.
Hi Matt, When our forefathers crossed the land to the West, they built a lot of ovens using ant hills. Apparently the consistency of ant hill dirt is very similar to your 1part clay & 3parts sand mortar mix... So, I wonder if someone has used this for a brick/mortar oven recently, and can give us some feedback?
I've been stalking you for a couple of years now. Lol. I think I want to go with your design. I have a fireplace insert that is directly behind my kitchen stove. I am a welder and can fab just about anything. I am thinking I can pull the insert out and use that space for the firebox that can be seen in the living room and go through the wall( which it does already), and build a cookstove in the kitchen. I can't figure out if or how I could do a bench in the living room.
Matt you're the best! I'd do this is a moment but mama is too domesticated. Do any ladies have a wood burning cook stove? How do you like it? Is it one of Matt's stoves? Pre-thanks a million!
Ed, cooked on wood stoves most of my life ..prefer them to electric, gas, etc...except keeping the wood split and kindled ;) ...came across rocket stoves a few years ago and began to design my own cook stove using rocket principles , the only one i could find close was on broaudio and he has been my go to guru for this build..love no air pollution and so much less wood used
Hi Matt, Great video! thanks for the tutorial on clay sand mortar, will be using it soon enough on my heater build (in Joyce). Do you know of anyone who has gone through the on grid build process who has installed one of your stoves with consent from code authorities? Does it fall into the classification of a masonry heating unit? Are your plans possibly the loophole needed to construct my future heater and still insure the new home? -Ean
Thanks Ean! So, the legalities vary from state to state and in some cases vary at the municipal level. You'll have to check your state codes, in many states it is as simple as categorizing the build as a site-built masonry heater. I have had a few people building to my plans go through the code process successfully. Hope that helps.
Nice to know my clay soil is a solid building material option. I have a lot of light colored clay. Also, not to be off topic, but I'm still toying with the idea of introducing secondary air through a negative space channel through the brick structure of the firebox and vent controlled at the firebox door. Ever seen that done?
Hi Thomas. Yes, channels through firebrick are the traditional way, and I know of a few rocket stove/cook stove builds featuring this type of secondary air delivery. I prefer the metal as it delivers super hot air to the combustion zone extremely quickly after lighting. With a brick delivery it will take far longer for the combustion zone to come up to temp and start burning efficiently, and in a mass heater often you are only burning one load. If efficiency isn't one of your primary goals, it should be satisfactory. If you are wanting to use your wood as efficiently as possible, I recommend a metal delivery. Hope that helps!
broaudio Matt, I know you use ceramic fiber in some of your builds and from my what I can tell, that's pretty much where the future of rocket stoves is going. I am planning my own build using ceramic fiber board and blanket and am concerned about the potential for high velocity gases eroding the board/blanket. Do you think durability is a problem? If so, do you think it can be overcome with the use of a product like the 3000 degree F (missou) by applying a thin coat to the board and actually rubbing it into the pores. Same for the blanket. Additionally, I have considered following up with a layer of ceramic fiber cloth, using the hot face masonry cement as a sort of adhesive past, and again, rubbing the cement into the pores. I would be ever grateful for any experience you have with the high velocity erosion I'm speaking of. Thank you!
I have not seen any degradation from contact with flame or flue gas. I do not feel it is worth while to attempt to "surface" it, I see no benefit to doing so. My suggestion is keep it simple, don't overthink it. My preference is bare ceramic fiber board cores and either a CFB riser or Pinheads Five Minute Riser, either will provide excellent performance and will last indefinitely in my experience. Hope that helps.
I want to build a RMH with water heating for shower room. I don't having welding gear. I'l be using cob or mortar for a lot of it. Witch is better for lb's and heating for space and copper coils/water ? I was thinking this design: permies.com/t/110574/Mini-rocket-stove-wheels-hot
Hi, New subscriber and follower here. I love the info and I am wanting to build a rocket stove mass heater. I like this concept of fire clay and sand mortar rather than portland/lime. My question is can you make fire bricks from this same mix, using a mold or a form?
You can make bricks using the method you describe and these materials, absolutely. Many successful RMH builds have been achieved using homemade mud bricks, or adobes. Search adobes here on YT and you'll find a lot of resources. As for firebrick though, I don't recommend it. The homemade brick will be great for the body of the stove, but aren't durable enough to use inside the firebox. Hope that helps!
My Clay/Sand Mortar Mix Recipe: 3 parts dry sharp sand by volume, 1 part dry ground fire clay by volume. Add water to desired consistency.
Fire clay: amzn.to/2ykT2B0
Sharp sand: amzn.to/2LJKqa9
I would add best to use washed soft sand and the addition of Lime at one part in four of above mix will improve the mixes stability without effecting the mixtures ability to be recycled.
I have learned a great amount of knowledge from your videos
Matt, I see you heading on the right path, To be able to extract every calorie of energy, burning safely and cleanly both for the air and more importantly in a professionally presented and well run way, praise aside, Simple Quick and Affordable design that gives Speed Convince and Reliability daily.. its all there!
Hello sir! I recently built a batch box rocket with a heated bench (stratification) in my living room, inspired by both yourself and Peter vanderberg. Just wanted to say thanks for the info and inspiration 😊😊
Always great information.
Very helpful as are all your videos, thank you so much
Have you used a lime based mortar? This was the go to in victorian England for chimneys. So far I've found commercial refractory mortar to be lime, clay, sand and cement. As far as I could figure out the lime makes the mortar more water/steam resistant. I imagine that the heat cycles produce condensation inside the heater making the mortar ever slightly damp and therefore creating 'steam'. Steam expands, hence the cracks?
Always a good day when Matt posts a video :)
Thanks for the video Matt, great timing as tomorrow we start building our brick RMH using your designs. Very excited! Regarding more design ideas - I'd love to see your take on a rocket powered hot water tank. I've got an old electric immersion heater and thought it would be cool to recycle the insulated copper tank for a rocket project.
Great video. I realised from this what fire clay is. Got a bag and expected it to be more clay like. Cob also works abit the same i think. It helps bind the sand. And the sand stops cracking.
Question Matt
Do you use this mix in all areas and with all the stones. Or is it for internal?
Do you have a video showing you mortoring bricks or can you point me to somewhere someone ?
3:53 Motar - Ratio 3 : 1 - Sand to Clay ( by volume )
11:57 add screened Ash from Rocket Stove
Mat, I went to get some sand where I purchased my bricks and they told me I needed portland cement with their brand of fire clay. Also said any sand would do even sandbox sand, they said sand is sand just different coarseness.
Hi Matt,
When our forefathers crossed the land to the West, they built a lot of ovens using ant hills. Apparently the consistency of ant hill dirt is very similar to your 1part clay & 3parts sand mortar mix...
So, I wonder if someone has used this for a brick/mortar oven recently, and can give us some feedback?
I've been stalking you for a couple of years now. Lol. I think I want to go with your design. I have a fireplace insert that is directly behind my kitchen stove. I am a welder and can fab just about anything. I am thinking I can pull the insert out and use that space for the firebox that can be seen in the living room and go through the wall( which it does already), and build a cookstove in the kitchen. I can't figure out if or how I could do a bench in the living room.
Did you dry mix? First
Matt you're the best! I'd do this is a moment but mama is too domesticated. Do any ladies have a wood burning cook stove? How do you like it? Is it one of Matt's stoves? Pre-thanks a million!
I always look forward to using my potbelly wood cook stove. But only do so in the cool weather months. I've also altered it a bit though.
Ed, cooked on wood stoves most of my life ..prefer them to electric, gas, etc...except keeping the wood split and kindled ;) ...came across rocket stoves a few years ago and began to design my own cook stove using rocket principles , the only one i could find close was on broaudio and he has been my go to guru for this build..love no air pollution and so much less wood used
Thanks @ Dallas & Zephyr Starsand
Can the cook top be ms plate 5 mm thickness?
they don't carry medium sand at the local stores, so i used the play sand, the results were not good. Will try again and special order the medium.
Hi Matt, Great video! thanks for the tutorial on clay sand mortar, will be using it soon enough on my heater build (in Joyce). Do you know of anyone who has gone through the on grid build process who has installed one of your stoves with consent from code authorities? Does it fall into the classification of a masonry heating unit? Are your plans possibly the loophole needed to construct my future heater and still insure the new home? -Ean
Thanks Ean! So, the legalities vary from state to state and in some cases vary at the municipal level. You'll have to check your state codes, in many states it is as simple as categorizing the build as a site-built masonry heater. I have had a few people building to my plans go through the code process successfully. Hope that helps.
Hey Matt what do you charge to build for a client?
Nice to know my clay soil is a solid building material option. I have a lot of light colored clay. Also, not to be off topic, but I'm still toying with the idea of introducing secondary air through a negative space channel through the brick structure of the firebox and vent controlled at the firebox door. Ever seen that done?
Hi Thomas. Yes, channels through firebrick are the traditional way, and I know of a few rocket stove/cook stove builds featuring this type of secondary air delivery. I prefer the metal as it delivers super hot air to the combustion zone extremely quickly after lighting. With a brick delivery it will take far longer for the combustion zone to come up to temp and start burning efficiently, and in a mass heater often you are only burning one load. If efficiency isn't one of your primary goals, it should be satisfactory. If you are wanting to use your wood as efficiently as possible, I recommend a metal delivery. Hope that helps!
broaudio Matt, I know you use ceramic fiber in some of your builds and from my what I can tell, that's pretty much where the future of rocket stoves is going. I am planning my own build using ceramic fiber board and blanket and am concerned about the potential for high velocity gases eroding the board/blanket. Do you think durability is a problem? If so, do you think it can be overcome with the use of a product like the 3000 degree F (missou) by applying a thin coat to the board and actually rubbing it into the pores. Same for the blanket. Additionally, I have considered following up with a layer of ceramic fiber cloth, using the hot face masonry cement as a sort of adhesive past, and again, rubbing the cement into the pores. I would be ever grateful for any experience you have with the high velocity erosion I'm speaking of. Thank you!
I have not seen any degradation from contact with flame or flue gas. I do not feel it is worth while to attempt to "surface" it, I see no benefit to doing so. My suggestion is keep it simple, don't overthink it. My preference is bare ceramic fiber board cores and either a CFB riser or Pinheads Five Minute Riser, either will provide excellent performance and will last indefinitely in my experience. Hope that helps.
I want to build a RMH with water heating for shower room. I don't having welding gear. I'l be using cob or mortar for a lot of it. Witch is better for lb's and heating for space and copper coils/water ? I was thinking this design: permies.com/t/110574/Mini-rocket-stove-wheels-hot
Hi, New subscriber and follower here. I love the info and I am wanting to build a rocket stove mass heater.
I like this concept of fire clay and sand mortar rather than portland/lime.
My question is can you make fire bricks from this same mix, using a mold or a form?
You can make bricks using the method you describe and these materials, absolutely. Many successful RMH builds have been achieved using homemade mud bricks, or adobes. Search adobes here on YT and you'll find a lot of resources.
As for firebrick though, I don't recommend it. The homemade brick will be great for the body of the stove, but aren't durable enough to use inside the firebox.
Hope that helps!
Yes, that helps. Thanks.
broaudi
Have you done an attached harage masonry heater?
I have not, but the garage slab is an ideal platform for a build. In the right setting I think it could be a great way to go.