Plunger tube, is an extension downwards of the chimney tube, to augment the height differential between top of the bell, and bottom of the bell. Hence, keeping more heat. Keep 10cm bellow the tube in this case. 5 is about right for the CSA of 314cm², in case of a 20 cm riser. Which i've drawn since i had the parts ready in another sketchup.
I made my first design a single bell, with several channels. Better to heat the cooking plate. Three vanes could be added; to block the cooking plate from heating, and also make a bypass for hard cold starts. I think you can count on 170C°/180C° on the cooking plate.
And Yep the bricks would do. Tho, it will be slow to heat up and work properly. It will be smokeless in five minutes. But take far longer to have that heat catalyst effect, or a glowing riser. Mine, is about 2cm thick, and takes longer than i like to warm up. Up to the point i have made the ramps out of insulating firebricks lately.
Plunger tube, is an extension downwards of the chimney tube, to augment the height differential between top of the bell, and bottom of the bell. Hence, keeping more heat. Keep 10cm bellow the tube in this case. 5 is about right for the CSA of 314cm², in case of a 20 cm riser.
Hmmm... That 5 cm is the absolute theoretical minimum. However, the gases need to go through a 180 degree direction change. From vertically down to vertically up, I would recommend at least 10 cm in this case, a 100% increase.
And another very important point: when the plunger pipe is leaning against a wall the gases can't enter from behind so about one quarter of the circumference of the pipe isn't used by the downwards directed stream. In this particular case the minimum allowance under the pipe should be 6.7 cm, plus the 100% increase mentioned above is 13.4 cm.
A plunger pipe in a corner is even worse, half of the circumference is blocked by the two walls in this particular situation. Taking this reasoning further, the open space below the pipe should be 20 cm is this case.
Every batch box rocket that appears to have a slow pulse like a steam locomotive when running flat out is sporting a restriction somewhere. Very, very often it turns out to be the placement of the exhaust opening. My own experiments all showed this behaviour until I found out the reason behind it. The development builds after I found out this possible bottleneck didn't show a pulse anymore. Including my own house heater and the 20 cm builds at Permies in Montana and at the MHA in North Carolina, both in 2015.
Yes Peter; i said 10cm minimum. Tho, it seems soo obvious, that i often forget to insist on the subject.
Absolute ideal situation, i reccomend 150% minimum, for a batch with a cooktop. Otherwise, more is better. I like teh bell oven aranhement in this drawing. May be the first one i did like this was for one of our Italian members. After or before i built my workshop rocket. I have the same arangement in the "barrel" radiator. I bet i could cook pizza in there. I have to give it a try now that i sealled the door a bit better.
But having the metal barrel in this spot is not good imho. Better to have mass, for the oven, and to release slowly the high heat stored. And cool the gases further down the line, with a cooking plate. This is not far from what i'm planning for my future flat. Obviously, i will try top load before it goes in there.
I received from prosiref : 50 brick Classe 23 10 isolating bricks (not suitable for firecontact) 2m of rope gasket (fiberglass) 25kg of refractory mortar up to 1500° for the core
I received a gun infrared thermometer
I bought at leroy merlin5*1m stainless steal 6' pipe. 100kg of refractory mortar up to 900° for the wall
I made a finishing plate to put on the top existing chimney For the damper I will do it myself
Im also planing to buy a CO and smoke alarm/detector to put inside my living space. I'm trying to source a cheap stove door so in case of maintenance I can quickly check inside the bell.
Final design should be something like this :
-really small heated bench. Could be used for wood storage. -oven door is on the back side -'plunger tube' for the chimney -batch top loading -batch box is regular 6' design (not a sidewinder) -Coper pipe for water heating molded around that :
Builder is coming next week, let's go
Last Edit: Oct 19, 2016 13:00:50 GMT -8 by yhomega
Well, one word of caution, carefull if you dump the stove pipe down in the ashes pit. There might be not enough roop between the pipe and sides of the hole for the gases to flow. You'll have to measure.
I cut the insulated fire brick today, really easy.
You can see the small channel under the bench and the opening on the ash pit. I will do a big opening in the stainless steal pipe and it should be fine, I will post picture when it's properly done just to make sure
My issue is more the size of the mass heater. A 6' is way too big in the middle of the room A 5' is a bit better, but still it's big!
I think I'm gonna move the old fireplace against the red wall (after installing a fermacell wall...) and build the batch box there. Well it's more work but if it looks much better I think it worth it.
The build has started, thanks to Jack (experienced builder) and Felix for the welding!
I have 2 more questions please (yes I know, too many questions already)
The fireplace has been moved against a wall, height is not an issue anymore (before, too high would have look weird) I can fully respect the riser length and keep 30 cm room above.
Before the chimney would have done 4.5 meters verticaly (down the floor up to the roof). Now It has to do 3 meters vertically 3 meters horizontaly (to get to the old chimney) then 1.5 meters up to the roof
Question 1 : Do you think I should isolate the chimney with rockwool? (above the ceiling and/or inside the old flue)
In the futur I would like to be able to heat water. I have this steal basket that is high in the bell (=high temperature) and offer good thermal conduction.
I think I could use a heat exchanger stick to the black basket but Im not sure how to do it safely. I tried to source more information online but nothing reliable. batchrocket.eu/en/applications#chb is not fully documented. how to avoid issue in case the heat exchanger run out of water? the pump stop?
How would you heat water safely with my design?!
Last Edit: Oct 24, 2016 10:27:48 GMT -8 by yhomega
martinm: any one here with info \ experience with heat (from a mass heater) distribution with ducts throughout two storey house ?
Sept 8, 2018 22:58:52 GMT -8
padica: Good morning, this is a wonderful subject, please someone can help me with the theme of double and triple combustion, how it is achieved, theory and design, thank you
Sept 15, 2018 7:13:40 GMT -8
wiscojames: I'm afraid you won't get a response to such a vague question - I suggest reading through some of the threads related to your questions before asking for an explanation. People will be very generous with their knowledge if your question is more specific.
Sept 18, 2018 4:48:00 GMT -8
daniel: in my experience as I am working now on something of that nature, I have thought of making a heat exchanger and distributing the heat through vents using a slower fan. Now after a few years I realize that mass heaters give out primarily radiant heat, for
Nov 30, 2018 12:48:38 GMT -8
coastalrocketeer: Anyone posting in this shout box... if you have something you want people to see and respond to, create a thread in the appropriate forum section... this is not the place...
Dec 16, 2018 18:10:49 GMT -8
vesuvius: High Temperature Glass options,
Jan 4, 2019 16:28:17 GMT -8
vesuvius: Do any of you have experience with using the glass from home oven doors on a rocket stove? I'd like to have a viewing port on my stove but don't want to fork out for new ceramic glass. Any thought as to whether it would take the heat of a rocket stove?
Jan 4, 2019 16:30:40 GMT -8
yaya: you dont need the blowair for that temp..
Jan 13, 2019 16:43:57 GMT -8
flybywire: Glass window from an old washing machine is designed to take high temps. Cheap solution to your need.
Jan 27, 2019 0:10:58 GMT -8
coastalrocketeer: Anyone posting in this shout box... if you have something you want people to see and respond to, create a thread in the appropriate forum section... this is not the place to have a discussion... it is for short announcements
Feb 7, 2019 0:11:23 GMT -8
coastalrocketeer: you won’t likely get replies to questions here, and it is not a spot that makes holding an ongoing discussion possible...
Feb 7, 2019 0:12:22 GMT -8
TexasGonzo: Sooooo glad I found this site! Its always rewarding to find such a super group of folks! To any and all, feel free to PM me anytime. Thanks for having me!
Mar 11, 2019 18:56:41 GMT -8
jlmtech: GADGET: CONSIDER USING A JET PUMP INSTEAD OF A BLOWER FAN TO INDUCE DRAFT; NO CLOGGING.
Mar 26, 2019 8:19:28 GMT -8
michaelegan: i am unable to open the sketchup files on my mac. I used sketchup a few years back but apparently the company now requires a subscription. does anyone have any advice/instructions on how to use the program or how to view pictures without spending money?
Aug 20, 2019 18:41:48 GMT -8
mannytheseacow: michaelegan: download AutoCAD student version for free... import .SKP
Aug 23, 2019 13:33:44 GMT -8
topbaza: hi everyone, been searching all over net and this is were i need to be i think!!
Sept 28, 2019 6:16:25 GMT -8
anounaki: Hi, why I cant upload photos when I make new tread to this forum?
Feb 28, 2020 2:09:40 GMT -8
ahansen: photos under 1 mb not possible?
Jun 4, 2020 0:09:21 GMT -8