Joe Danielek

What about composting toilets? What are the County and State laws in your area? What is gray water, black water? Makes perfect sense, low flow toilets to save water then you double or triple flush... politicians.  

What weights more, a ton of sand or a ton of concrete?

Which one stores the most heat?

Which one releases heat faster?

Which one takes the longest to heat up?

I'll be using a sand heat sink with my Rocket Stove.

Eric Hroboni wrote:I've made a few more upgrades. They are definitely making the greenhouse more evenly heated. I put a box around the blower to draw air lower to the  floor. And also put inline duct fans in .

Eric, how you doing?

Met earthmover his dad and son on the 36 acres to go over placement of roads, 90’ walipini and excess dirt. Heavily wooded with old growth Pinion Pine and Juniper trees the dad asked if we were going to heat with wood, this lead to a lively conversation about rocket mass heaters that they were familiar with. Told them we were leaving the old growth as is, no cutting or clearly of trees opting for growing trees for fuel with litter for composting. The Pinion wouldn’t be good for a rocket mass heater giving its sap content that would be like pouring turpentine in the feed tube leading to incomplete combustion. The Juniper being twisted would be too much work getting it to feed tube size.

Excellent subject, agree that a RMH is best looked at as a system from fuel sourcing to exhaust that can be very carbon negative.  

paul wheaton wrote:

Steven Kovacs wrote:Thanks for this, Paul.  You've clearly put a lot of thought into the issue.

More like:  my brain is infested with a huge amount of thoughts on a lot of topics.   Lovely people then ask a simple question like "What do you think of LED lights these days?" and I am instantly tongue tied because my answer is not a simple "I still prefer incandescent."  My answer is huge.   In fact, my answer is even larger than what I provided, but I need to stop at some point.

Just started reading this string having lots to say and will later. Excellent intro Paul, my light color preference is 3000k that leans towards incandescent bypassing CFL's with LED's having a place.

After that, I decided I'd rather live in the dark and scrub my clothes on a rock!

LOL

To reduce exposure to ceramic dust from cutting, a rabbit joint could be fabricated by building a riser box inside another riser (two layers) and alternating/off-setting the joints. The butt end connection (corners) could be pinned along the joint seam with small metal rods. The assemble can be held together with an angle iron frame.

This joint would assure tight fitting (square) surfaces at the corners and would not compromise the board strength by cutting a rabbit reducing wall thickness.

thomas rubino wrote:Hi Neil;
No, Peter did not OK my burn tunnel being longer. I did that all on my own!  
Originally I built an 8" J tube using perlite and clay. A Walker cast core. and a Walker style cast riser as well.
Worked beyond awesome! Barrel top temps of 1100F!  
What did not hold up was the feed tube. By the end of the 2013 season, my feed tube had enlarged to the size of a 5 gallon bucket.
I decided to build a heavy brick core to replace it.

I located a source of free firebricks....
I made the burn tunnel roof apx. 13" - 15"" long. (Don't remember the exact number)

I did that because I did not have a clue... just like any first timer. Bigger must be better right?
And besides it made setting the barrel much easier...  
Remember in 2013-14 information was not as easily available as it is now. There was one book by Ianto Evans and there was Permies!  

I loved my new core, for the fact that wood had no effect on it. My feed tube started out at 7.5" and stayed there! Hooray we are rocketing now!!!
Long about the middle of winter I started having draft issues??? Why, I was keeping my burn tunnel cleaned out?
It quickly progressed to not burning worth a damn... smoke back was a daily problem! That was not acceptable!
My barrel of course has a removable lid, a quick look inside showed no issues in the riser.
As stated earlier, my transition area was almost full and my 8" horizontal pipes had maybe 2" left open...  for the entire horizontal run!  That's over 20' of pipe filled with ash!
That was when I discovered that a leaf blower can blast out your mass...BUT it make's one huge pucking mess!

A core rebuild happened in the middle of winter that year... let me tell you, it was very scary taking apart your only source of heat in a Montana winter.
That was when I learned all about WHY we use clay not refractory  to mortar our bricks...  A piece of cake to tear into that core. All the cob went in a bucket and was rehydrated to be reused. A scraper cleaned the bricks up in moments.  Within 4 hours of walking in the greenhouse that morning I had my core rebuilt and was lighting a new fire!

Moral of the story here. The innovators,  Peter Berg , Matt Walker , The Wisners , Ianto Evans. They tried all the configurations they could dream up.
They quickly learned what would work and what did not work.  Eventually high dollar test equipment was utilized to fine tune their results.
They have openly shared this information with the world... we all owe them a huge thank you for telling us how they accomplished everything.

I do not believe there is a post showing that core rebuild.   I may still  have photo's on my computer.

Thomas, how is your ash build up issue been?

Joe Danielek wrote:

Another assertion that of the ‘push–pull’ theory doesn’t make sense that Thomas indirectly dispels himself by stating “... however you need to start and keep a steady draw thru the entire system.”, thus the bypass blastgate for sale on your site. For me the secret to system efficiently is at the feed tube by fuel size and rate of feed to assure a complete burn up the riser.      

Just read THE ROCKET MASS  HEATER BUILDER'S GUIDE by Erica & Ernie Wisner. They never mention PUSH only 'draft' and 'draw' which is interesting.

Fox, have to agree those leading the exploration and innovations of Rocket systems indeed deserve recognition and respect. There is for sure some neat stuff out there with more to come where the ‘open source’ attitude by most is most welcome. That said I do have a few ideas to enhance RMH’s operational characteristics and safety, untried at this time but are tweaks to existing proven/employed tweaks and concepts – operational enhancements (AHA moments!!!).

Configurations and materials to build Rockets and how they are installed are only limited by ones imagination and understanding... how they understand, where those doing it have put themselves out there. Will Rocket Mass Heaters ever be taken-up by corporate research is a good question. For that to happen the personality of each system has to be eliminated to standardize for operational and repeatable results where those interested in THE DRAGON will most likely shy away from a mass produced system(s), I will.

My driving design factors are waking up to a warm space to start the day in a remote off-grid location, a RMH system that puts the majority of the heat into a heat sink (earthen floor). Employing a longer firing cycle once a day in the evening, overheating of the occupied space during firing is a major factor needing to be avoided. The structure will be a 200 sq. ft. stick frame on an insulated concrete footer/stemwall, a sleeping shack for 8 complete with loft space.

I’m looking for comfort waking up to start the day in the wilderness... getting a restful night sleep or not being hesitant of going outside in the cold to take a leak. Girls will have accommodations inside for business.

This post titled “The need to insulate the riser is driven by what?” might be seen as a trick question to some as there’s several answers as well as positions, some absolute, others not. I’m not absolute either way in fact today ceramic board for the J-tube is being consider in conjunction with dense fire bricks, this will eliminate any type of brick mortar being needed for the burn tunnel and riser assembly allowing elastic movement under fire (the feed tube would be mortared).

So my use of an insulator has nothing to do with increasing riser temps as I don’t think it’s needed whatsoever especially with my tweaks.        

Fox James wrote:
I was hoping one of the more experienced designers would chime in as it is an interesting subject….