thomas rubino

Hi Cerbu;
When you follow Peter's plans to the letter, your results are virtually guaranteed!
A true master builder, we are all lucky he has chosen to freely share his designs with the world!
Thank You Peter, from the rocket mass heater community!

When I was attaching metal art to the brick bell of a mass heater, I chose to use rare-earth magnets epoxied to the bell, and my metal art attached to them.
On my double skin bell, this has worked perfectly.
I used the same method on Shorty, my single skin bell.
It seemed to work perfectly... until we had a cold morning, when I added an extra batch to Shorty.
Oh my, she really throws heat if you double up... unfortunately, standard rare-earth magnets do not hold as temperatures rise.
Permies rocket scientist Fox warned me about his attempts to use RE magnets, which failed as soon as the temperature rose.
And indeed he was spot on, as the second load in Shorty got to roaring, my metal raven art suddenly fell to the floor!
It was not damaged. But it refused to stay on the bell.
A search online and I found this https://www.kjmagnetics.com/products/high-temp-magnets?gad_campaignid=22284168230
Good to 428F or 220C. I doubt I could get the outer skin that hot on Shorty; our house is way too small.
Standard rare earth magnets are only good to 176F 80 °C

Cost is negligible, and they are holding perfectly!
If you want to add bling to your dragon, high-heat rare-earth magnets are the way to go!

Hi May
I also am not quite sure what you are describing.
If you are attaching the new room to the existing house, then the original foundation will be providing support on that side.
Your new room will be 12' deep.
If it were me, I would use soni-tube forms and pour concrete piers every eight feet 3' in the ground along the outside edge.
Set your black locust on them.
For a solid floor, depending on your floor joists, I would also add a support beam and piers at six foot.
This  beam could be supported with piers of black locust in the ground
If using concrete is not to your liking then using your black locust posts on the outside edge would work.
I have heard of B.L. posts over 100 years old still supporting buildings.

Hey John;
I mentioned the Walker half-barrel method.
It occurred to me that you may not know what that is.
55-gal barrels are cut in half lengthwise and set end to end on the walls for the length of your bench.
The ends are removed, other than a couple of inches, to retain the rounded shape, and cob is used over the barrels.

Hi Carla,
I am every bit as impressed with Shorty's ability to warm this old leaky house, while just nibbling wood to do so!
She has a large presence in the room, but she sure is easy to look at!
I started out in 2013, building my first J-Tube.
I was an instant believer. Heating my non-insulated outbuildings with no fire overnight was an eye-opener!
I spent years telling complete strangers how awesome these stoves are!

But now, having built Shorty inside our old home, I have increased my level of Awe; these Montana masonry heaters are way beyond any expectations!
If you had met me in 2014 and thought I was fanatical about building RMHs, well, try bumping into me in 2026...

Anyone who comes by to visit has to march from seeing my Shop Dragon, then into the greenhouse/art studio to visit the Studio dragon, and finally, I bring them into the old cabin to meet Shorty.
Before they even get to view her, they notice how cozy it is, then we move into the living room, and they are shocked that there is no fire, and I cheerfully explain it has been out since eight am, and that I had no plans to light it again until 7-8 pm that night.
For those lucky enough to be here in the evening, they get to see Shorty in full burn, through her large  7" square window, which, thanks to Peter's design, stays completely clear for the entire burn, with dancing flames illuminating the room.

These stoves are classified as a Masonry heater under the International Building Code.
When built properly, they are insurable in most places.
A child playing with matches has a greater chance of burning down a house than an RMH.

February 17th, 2026.
This Morning I fed Shorty the last of her measured wood.
So far this season, from Oct to mid-February, we've burned one cord of wood!  
Perhaps, we will use 1/4-1/3 more by the end of April.
We like it warm; I would rather open windows than put on a blanket.
The peace of mind when leaving home or when going to bed, knowing that there is NO FIRE burning, and your home will not burn down, is priceless!
Using so little wood is the icing on the cake!

Hi John;
The trick is to use a locally available material for the walls and roof.
For example, concrete blocks, large square stones, or clay bricks. Some folks use metal; you can even use wood as your box, away from the core (J-Tube).
Then there is the Walker, half-barrel bench.
Any of these materials can be finished with cob if desired.

For your core, firebricks are the most common.  Clay bricks can be used, but they will not last long term.
Or, you can use fireclay mixed with perlite and cast a core yourself.

Sara;
On the Shorty core, the riser exit does not have to face forward; it can be reversed and point to the rear.
A White oven could be built over the core.
I believe a build is underway that is adding that feature.

Peter may offer more info on this.

I know, I miss the "wing" windows, which were a wonderful feature that went away in the late sixties and seventies.
A/C, window defroster, cigarette smoke ventilator, they were an integral part of your car.
My 67 Camaro had wing windows, and my 1968 Camaro had "flow-through" ventilation.
My 1973 Ford Highboy pickup has them, but the newer Ford pickups do not.

Knowing that a couple of our female staff, and probably quite a few others, enjoy seeing the old trucks.
I thought I would snap some pictures to share.

The First truck is a 1939 Chevy dual-wheel, 1 1/4-ton truck with a 2.5-yard dump bed.
I hauled all the gravel for my shop building with this truck in the early 1990s.
Still sporting the original 216 cubic inch with babbitt bearings, all six volt.
This 39 body is sitting on a 1942 Chevrolet frame and running gear to make it more operator-friendly.
In 1939, they used an enclosed driveline, called a torque tube. A bad universal joint required removing the rear differential for repair.
By 1942 (no doubt WW2 had something to do with this), Chevrolet had switched to a Hotchkiss design with an open driveline, allowing for quick repairs in the field.

The second truck is a 1953 Chevrolet 3800 (ranch wagon). Often referred to as a five window, with the curved rear corner windows.
A single wheel 1-ton truck with a 10 ' bed, I hauled a lot of firewood with this truck.
With the four-foot racks and a ten-foot bed, there was never any argument about whether I brought a full cord or not!
When I got it, it had the original 216 straight-six cylinder engine. I replaced it with a 1959 235 engine with full-oil pressure bearings (no babbitt)  
I then converted the entire electric system to a "modern" 12-volt system for ease of starting and brighter lights at night.
This truck was my daily driver for many years.

Both trucks were running great, backed into place, and turned off, thirty years or so ago...
With a charged battery and some fresh gas, either will start up and go back to work!
They sure knew how to make quality, long-lasting trucks in those days.