A Baby Dragon Roars!

Hi All;
Today was the day. Things went very smooth. Got the last course of brick laid. Got the hardy board cut to size and mudded it down. Mudded in the barrel to the roof. Pulled out the old 6" pipe and stuffed in the 8" . No collar, no cap, it leaks but its thru the roof ! Have to wait for some snow to melt before I venture up on the outside of the roof.


And then I fed my dragon for the first time !  She liked it!!  Started almost right away! Barrel top temp went over 830 F within a few moments.  Exhaust stack started drawing instantly!  After an hour or so I stopped seeing black smoke and started seeing steam !  Only ran it for a little over an hour. Roof temp was over 120F , bricks were thinking of showing some heat. The exhaust stack was up to 80F when I quit feeding her.  
Whoo Hoo !  No leaks yet.  

I believe that my "5 minute riser" was a huge factor in the success of this first burn. Not having to heat up the riser and having a ceramic board core that also did not soak up any heat allowed the core to shoot up to rocket temps much sooner than with any previous core and riser combo's.  


Using the ceramic fiber products increases the cost of a rmh by at least several hundred dollars.
For some this is to much investment. Tried and true traditional rmh building methods (rocket science) will always be avalable, at low cost.
For those who can afford it and wish to follow in the inovaters leading edge path.  There is nothing better to use than ceramic products!


Tomorow, I need to get some auto work done. I plan on running the dragon hard all day ! I'm really looking forward to it!

Hey Thomas,

Is an hour warm up normal till steam starts to appear? I would think with a ceramic fiber core it would only take a few minutes.

Congratulations Thomas!  A very proud father of a healthy baby dragon!
I bet you'll be grinning all day long tomorrow as you work on your car, hands not freezing on cold metal.
Do keep us informed of all your observations as time goes on. After all, watching it grow I feel like a surrogate father too!

Hi Mike;  New stove, hardly above freezing .   Wet clay , lots of wet clay.  400-500 bricks at 30 something degrees . Shop temp was right around freezing. I think it did rather well :)
After all the poor thing just hatched! Think of the dark smoke as her yawning...

To answer your question.  Yes, once that bell is dry and warm. I expect I'll get heat shimmers in 5-10 minutes. I am definitely a new fan of ceramic fiber!  

Gerry; Thank you very much!  Your suggestions and support have been a great help, especially the part about a temp roof !
You bet I'll keep reporting,  nothing I like better. This is my first large bell. Lots to learn about.
Did you notice I have left over bricks ? ? ? Must need another rmh someplace...

Thomas,  keep these to mâle the double skin.

Thomas, you've experienced now what a virtually frictionless heat extractor can do. I bet the draw was present even before the ceramic core heated up!

Lit her off around 8 am this morning and I have kept it burning strong all day (its still burning now 5pm) no smoke other than start up.  Plenty of steam early but since noon I have got nothing but heat shimmers coming from the stack!  She's dry and warm now! And already the shop is So much warmer than the old double barrel stove ever made it !!!

No leaks so far around the barrel... ceramic blanket seems to be doing the job. Cob has some cracking and I'll smooth it up as needed.
 
Brick temps vary. The fire bricks under the barrel, are running around 225 F .  The red clay bricks near the barrel are 160F or so,  just below the roof, bricks are 130F , 3 bricks down from there they are 140F down at floor level its 75F one brick up its 100F .  The exhaust stack topped out at 150F and seemed to run around 130F most of the time.
One really nice reading is the concrete slab temps,  within my insulated area, slab temp is 65F +- one inch away on the uninsulated side, slab is 45F !!!  Consistent all the way around , the insulation is doing its job !

Now about the Dragon her self...   I am seriously impressed, this thing roars.... like loudly!  Makes my greenhouse rocket look and sound puny !  Started out strong and never slowed down all day!  If it got quiet I knew she needed feeding. No fire trying to climb up the feed tube, just solid flames shooting up the burn tunnel.  I do not have a Peter chanel built for this yet but I will.

I'm letting it go out for the night. I'm very curious what the brick / slab temps will be in the morning.

7Am) Outside air temp is 33 F ,  Brick temps are very uniform at 52F ,   slab temp is 62F in the insulated area and 45F one inch away in the uninsulated area!  
Results are clear... INSULATE under your rmh !

EDIT)  9Am, just relit the stove. Bricks were down to 48F . Used the same starting method I use in the green house.  Block most of the burn tunnel with larger wood and start your kindling behind that. Draw was immediate, even the news paper fire on top did not try to come up the feed tube.  The fire never faltered but it took a few minutes for the kindling wood to really get going.
My core/riser in the greenhouse gets roaring faster on startup but that is the only thing better about it! Ten minutes in and the shop is roaring... greenhouse is rumbling...still thinking about it.

Hey Thomas,    When I originally built my heater in the workshop which has a dirt floor, I only laid down patio pavers as a foundation - partially due to ignorance and also knowing it was all just an experiment at this time.  All future modifications were made on top of this layer but I could tell with each modification that the bricks were spalling and cracking more and more but was too lazy to go the extra step of a better suited material and insulated foundation. As a compromise I've always left some ash on the floor as an insulant but now knowing that all parts make up the whole and you can't really skimp when your going for a long term build, things need to shift. I think once heating season is over will be the time. Perhaps ceramic fiber and a 5 minute riser will be on the roster too!

I've never tried that way of lighting...gonna have to try it out. Thanks!

Congratulations Thomas! That sounds amazing. I'm already trying to figure out how to build one of these in my shop, which is 15 feet of one end of a shipping container that already has too much stuff in it. Guess I'll need to build a bigger shop with an 8" or 10" in it. My wife will be thrilled with that one, Ha!

I likey.  Very cool build, Thomas.  It gets me thinking differently about a project I have rattling around in the space between my ears.

I was thinking of putting an RMH in my mid-sized (stationary) school bus.  Presently there is an inadequate wood stove near, but not at, the back door.  My thoughts were to put a temporary RMH in there, with a pipe bench (not a bell), and use sand as a mass.  I would like to put the feed tube and riser/barrel where the present wood stove is.  The problem is that not too far towards the front of the bus is the passenger side rear wheel well hump, which is covered with some kind of plastic.  I would like to have my mass heater pipes head in that direction, but maybe I should insulate the plastic, and have a bell in that location, thus not having to route pipes up over and then down on the other side of the wheel (which I think might potentially mess with the draught)?  What sort of material is used, or can people recommend to insulate under the structure of the bell?  What sheeting is used against the insulation and providing the base of the structure of the bell to be built on?  How hot does the ISA (internal surface area) of the bottom of the bell get?  Can regular bricks be used instead of fire bricks for the bell?  I seem to think that they can, without a problem.  Presently there is a floor in the bus made of half inch plywood laid on top of two inch foam.  Same materials on the short wall below the row of bus windows where the bell would be.  Any thoughts?

Greetings Roberto;
Thank you, I couldn't be more pleased with it!

So lets talk about your bus.    Is it permanently, or at least sort of stationary ?  I hope so, as no clay construction will last long driving down a gravel road.

Isolating the bell/bench from your floor is easily done with spaced clay bricks, laid horizontal, with at least 1/2" or more cement board on top. Some folks have put a foil layer down on the cement board to be sure.
Your wall would use the cement board as well though 1/4" would work.  You could use ceramic blanket or loose perlite for insulating at the wall.  The wheel well hump would be best covered with ceramic blanket too. (glass top ovens have a ceramic blanket that can be salvaged)


Floor temp under the bell or bench should be no more than 200F max, most likely more like 125F or less.  Under the core your looking at 500+F or more. (note) the floor in a bell is not counted against ISA.
Your core should be built on a perlite or ceramic board base.  
Yes, regular brick is fine as long as the riser is under a barrel.

You may find that unlike your inadequate wood stove, the barrel of a rmh may run you rite out the bus! They do get hot.  3/4 covering the barrel with cob helps control radiated heat.

One nice thing about a bell over a bench with pipes is ash buildup! Pipes must be checked and cleaned at least every season for sure. I'm thinking you could go several years if needed with a bell.

Why wait any longer ??? (other than its winter..)  Try your hand at this , I'm sure there is nothing else needing doing on your homestead in the middle of winter :)  Being warm … its overrated anyway... Right ?

thomas rubino wrote: Is it permanently, or at least sort of stationary ?  I hope so, as no clay construction will last long driving down a gravel road. ...



isolating the bell/bench from your floor is easily done with spaced clay bricks, laid horizontal, with at least 1/2" or more cement board on top. Some folks have put a foil layer down on the cement board to be sure.
Your wall would use the cement board as well though 1/4" would work.  You could use ceramic blanket or loose perlite for insulating at the wall.  The wheel well hump would be best covered with ceramic blanket too. (glass top ovens have a ceramic blanket that can be salvaged)


Floor temp under the bell or bench should be no more than 200F max, most likely more like 125F or less.  Under the core your looking at 500+F or more. (note) the floor in a bell is not counted against ISA.
Your core should be built on a perlite or ceramic board base.  
Yes, regular brick is fine as long as the riser is under a barrel.

You may find that unlike your inadequate wood stove, the barrel of a rmh may run you rite out the bus! They do get hot.  3/4 covering the barrel with cob helps control radiated heat.

One nice thing about a bell over a bench with pipes is ash buildup! Pipes must be checked and cleaned at least every season for sure. I'm thinking you could go several years if needed with a bell.

Why wait any longer ??? (other than its winter..)  Try your hand at this , I'm sure there is nothing else needing doing on your homestead in the middle of winter :)  Being warm … its overrated anyway... Right ?

 Thanks for the info, Thomas.  The bus is stationary.  I don't live in it at present.  I Still have to gather more materials and cobbing in winter up here is not practical anyway.  I might remove that section of wall and go against the actual bus wall which is steel with a thin rock wool insulation.  I like the idea of salvaging ceramic blankets.  

thomas rubino wrote:7Am) Outside air temp is 33 F ,  Brick temps are very uniform at 52F ,   slab temp is 62F in the insulated area and 45F one inch away in the uninsulated area!  
Results are clear... INSULATE under your rmh !

EDIT)  9Am, just relit the stove. Bricks were down to 48F . Used the same starting method I use in the green house.  Block most of the burn tunnel with larger wood and start your kindling behind that. Draw was immediate, even the news paper fire on top did not try to come up the feed tube.  The fire never faltered but it took a few minutes for the kindling wood to really get going.
My core/riser in the greenhouse gets roaring faster on startup but that is the only thing better about it! Ten minutes in and the shop is roaring... greenhouse is rumbling...still thinking about it.

Hey Thomas,  I've been trying that way of lighting my stove these past few days... I really like it! Thank you!  :)

Also, just wondering if at some point in time you'll be adding more bricks (since you have them after all ! ) to the inside the bell to increase the ISA?
Mainly wondering because if your getting such a great draw then why not see how much more heat you can extract before it starts to hiccup? ....and before you loose your temporary roof !

Congratulations Thomas!!!

When I finish my Rocket Oven, you are making me rethink that my next project may be a RMH with brick bell and not a tradional J-tube/mass bench RMH.  I will be reviewing all your prior well documented posts again and starting to plan.  Need to acquire more bricks.  I have plenty of insulated firebricks but need to get a load of used regular bricks for the bell.  Thanks again.