Many years ago I used to make metal wood burning stoves out of all sorts of junk, I used pyrex casserole dish lids for the door windows on many of them. They were fine so long as you kept the flames off the glass and didn't touch the hot glass with anything cool. There's loads of them available in thrift / charity / secondhand shops, so cheap enough to replace.
ronyon Correct, Walker doesn't use insulation. And although his numbers are pretty good, they aren't as good as the original PvdB batch. I've always liked the idea in the original rocket stove of isolating combustion and heat harvest, so I thought adding some insulation might be a good idea. However, following the more recent comments of Shilo and Adiel following their collaboration with Peter that achieving proper mixing seems more important than adding more oxygen, I'm not sure if it will make a difference, or if so, how much. Seems it would be worth some testing with/without if I can get my hands on a testo.
numbers are pretty good, they aren't as good as the original PvdB batch
My experience has been the opposite. YMMV.
Oh! I was taking my conclusion from Peter's response early in your "riserless core" thread (http://donkey32.proboards.com/post/16866/thread). Maybe I'm interpreting that wrong, or maybe there has been other work that I'm not aware of, I'm happy to be corrected.
Finalizing secondary air. Lacking an angle grinder I opted to drill 52 holes at 3/16" each for a total of roughly 1.5"csa (less, I'm sure, due to the added resistance of flowing through a hole vs a slot). I was curious to see if the holes would "jet" into the gas stream like the overhead secondary air pipes / holes in my box stove. No such luck. The flow was so fast that, while air visibly exited and produced secondary flame, it didn't appear to create additional turbulence
Rough mock-up of the fuel box and afterburner, with a single piece of salvaged 36" insulated flue pipe as the stack.
Fire box with secondary air tube installed (offset to the right due to lack of ability to bevel bricks at this moment)
Half-inch ceramic fiber lines the afterburner. Ceramic glass added on top later to observe flame pattern.
First fire lighting. Note lack of turbulence at low burn, fire drawn directly toward exit.
As the fire intensifies, it picks up a ram's horn on the left, while the right side is swept straight up the flue with no additional mixing.
In this snippet the glass has burned clean and I'm attempting to show secondary air exiting from the injector holes.
Shot of the burn chamber after the fire went out. Primary air was completely blocked, the fire fed from all directions through leakage between the dry-stacked bricks. Walls seem pretty clean, soot only in corners. More ash than I expected, but incredibly light and puffy, and a very few bits of charcoal left. How does this compare to what remains after others burn down a batch box?
Modified the afterburner by adding a wall two bricks high to the right of the port to force gases up and hopefully encourage formation of a double ram's horn / better mixing. Seems to have worked well.
Overall *very* happy with this build. Despite being only dry stacked with lots of visible gaps, it was easy to tune to a smokeless burn. In fact, once up to temp (~32F outside), its dirtiest burn smell was at least as clean as the cleanest burning smell that I get from my box stove, and the clean burn smell was nearly indetectable. Looking forward to refining, figuring out a door, and bringing it inside! Any and all suggestions / comments welcome.
I would think the leftover ash would decrease as you insulate the burn box and close off the gaps. The glow phase was probably shorter from the box cooling down faster and losing some draft to keep glowing?
Vortex, by the way, how does the leftover ash bed compare to your firebox? Do you get a few lumps of charcoal left over, or does it pretty much all burn up?
Usually everything is reduced to fine white ash, occasionally I get one or two fingernail size pieces of charcoal left, never anything more. Normal firebrick makes the fire less efficient at the start because it's sucking heat, but it gives it all back at the end of the burn.
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
dcoyte: I am planning to use a cast iron heat exchanger out of a hydronic boiler set on top of my rocket stove, flue out the top. There will be a pump moving the water through the heat exchanger into an unpressurized 2000 gal tank. Any thoughts?
Dec 31, 2021 6:45:55 GMT -8
syekoms: Yes just found this forum am in Josephine county.
Jun 17, 2022 12:53:32 GMT -8