On a 6" system the chart reads 4-5/16" for base. What are you calling the base? I see everything else labeled or easy to figure out, but that one is confusing me. Is the masonry portion of the riser undersized and then a 6" riser placed on top of that? I have build a couple rocket stoves and see a much more practical application to the batch box design. Thanks for your help.
What is called "the base" is in in fact a base measurement, used to scale all the dimensions of the batch rocket. The base has a fixed relationship to the diameter of the riser. So it isn't the physical base of the firebox or whatever.
The riser need to be the same diameter and shape from top to bottom in order to avoid friction in the flame path which is spiralling up. One side of a square riser is used as the fictional diameter, because of the aerodynamic disadvantages of a square duct as opposed to a round one. An octagon riser is a close approximation to a circle, so those can be the same cross section area.
Speaking of riser height... For a 6" the base # is about 4.3125, math shows about 44" or so from floor of firebox, right? Morticcio's build appears to have a shorter than suggested riser. What's the lower limit on height? Eric VW
Approx. 1000mm (40") - the riser in the batch box is 350mm (14") + the riser extension (as in the bit that sits on top of the cast batch box) is 650mm (26") long.
Not in the house yet - daughter got married just before Christmas so wasn't allowed any distractions! She now wants one in Italy so I can see that being built before this one!
worse places to be than italy. can be cold this time of year though depending on where you are. when i was working over there near bolonia, and we needed the sort of stuff you get in B and Q i was pleasantly suprised how well stocked the local hardware shop was.
Thank you so much for all the work and results posted. I am new and as I start my design of the mass heater in my head, I have a few questions.
1)The P channel on a 150 diam system is 54W x 16H, what is the length of the port overhang? Is there some method to figure this out or trial and error?
2)Is it possible to have a dual exhaust (mass bench on either side), say 75mm left and 75mm right of the stove to meet back up to a 150 exhaust up a chimney? or would I want 150mm both sides to not restrict flow?
This is all very new to me and I can't wait to create a working rocket.
Thank you again and I look forward to the point when I can have a real discussion with all of you.
The firebox internal dimensions are 30cm wide 30cm high and 50cm deep. When a 18cm riser calls for 26 wide 39 high, and 52 deep.
I was wondering if it was Worth narrowing the firebox. Since it's ceilling is lower. CSA of the firebox is 900cm² while the 26x39 makes out for a 1014cm². Pretty close. Air speed in my firebox should be a smidge faster. But when burning fully, i have a bit more wood surface exposed. So more unburned gases.
I know that as a barbie core, exept when fully hot, it was smoking. But my riser is only in the 80cm range, while it needs to be about 130cm.
I can always make another firebox. But for the moment, i'd rather not.
What do you say? It would have door, P channel. I barrel on top. Followed by bells.
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
belgiangulch: Photo's are possible. They must be downloaded elsewhere and the image url (adress) is copyied.
Sept 14, 2020 7:26:15 GMT -8
belgiangulch: While creating a thread click on the small picture in the banner above the reply. A box pops up, paste the image url in the box. Pay no attention to the huge list of numbers and such.When you finish and hit reply your post with pictures will come up.
Sept 14, 2020 7:29:27 GMT -8
deadstarsstillburn: Hi there. I was directed this way by folks on the Permies.com website and am hoping I can get some information on how a total newbie can get started designing, siting, building, and not-dying-in-a-horrible-house-fire with a new RMH in a 160-year old home
Oct 21, 2020 6:52:10 GMT -8
deadstarsstillburn: The people over there recommended either a 6" batchbox or an 8" J-tube. I don't know what those are but am going to try to figure that out. What I need is a blueprint that I can scale to fit the need for my house. I have something likne 5000 square feet
Oct 21, 2020 6:53:00 GMT -8
deadstarsstillburn: but I do not need to heat all of it by any means. probably only need to heat half of that, maybe less.
Oct 21, 2020 6:53:15 GMT -8
deadstarsstillburn: moreover, the house has 3 storeys (large attic) so I assume if I get very efficient heating on the ground floor, that will go a long way toward heating the upstairs as well, no?
Oct 21, 2020 6:53:59 GMT -8
BenAlexanderT: Happy new year everybody. I wish you the best
Dec 31, 2020 15:06:14 GMT -8
Solomon: Anybody in Southern Oregon, in Jackson or Josephine counties?
Jan 16, 2021 21:54:43 GMT -8
gnomedome: i realsie this is from 2009
Apr 14, 2021 8:30:44 GMT -8
gnomedome: i realize this is from 2009 id love to see the photos from this ..as im looking to build a sauna soon similar to this .... if anyody sees this post firstname.lastname@example.org..... the photos in this post did not show up
Apr 14, 2021 8:32:00 GMT -8