William James

For me, as someone who had Waaaaay too much comfrey AND is has an Ag-businessthe problem is how to sell it.
There are products on the market that contain comfrey but i generally think the market is negligible, apart from home-made creams and oils potentially being sold at farmer’s markets.

Hugely generous plant without much economic use. really a shame.
W

I’ve looked into it superficially. A lot of the negativity surrounding comfrey comes from one study where they overloaded rats or pigs and then found liver damage. Even if anyone would never consume the amount in the study , it kept the bad rap.
William

Does anyone think some sort of repair/restoration would be easy or worthwhile?
W

tony uljee wrote:could be that the machine was running far to hot and the core has overheated causing the varnish to melt and leak out between the laminations of iron plates.

That’s kinda what i was worried about. The machine runs and welds. Should i be worried a out using it??
Thanks
W

John C Daley wrote:I dont know what you mean by ' Image says it all"
I use arc welders a lot, but that plate has inscriptions I am having trouble discerning.

The copper plates have all kinda of bumps gunk on it. They are hard almost like metal. Doesn’t wipe off.  Thanks for the manual.
W

Hi, found some strange stuff on the inside of an old welder i’m planning to use. Image shows it all.
Thx
William

Gerry: I Didn’t use the bench as a thermal mass storage because
A) that would have required a manifold, something I’m hesitant to build since it seems beyond my capabilities.
B) I thought wrongly that it might store some heat anyway.
C) the bricks around the insulated heat riser and the stone on the top hold heat.
D) This is a small little room where we make morning coffee or will go to when it’s cold and we’re working outside, so not much need for prolonged heat, although i made a fire at noon and at 7pm the room was still comfortably warm.
William

Hi Gerry. Thanks for the reply.
1) exhaust chimney not insulated. i could lokk into that.
2) the bench and “volcano slope” are just cob and old clay bricks. No pipes/no manifold. They don’t seem to collect much heat which is unfortunate.
3) i think internally the heat riser is about 30cm. I realized too late it was too big but the firebrick slabs didn’t really fit together well and i learned later how easy cutting brick is.
4) heat riser is insulated with perlite and surrounded by galvanized sheet roofing pounded out flat.
5) fire tunnel il 60 cm and 17cm tall. I built an extra front-piece to get the wood loading thing up higher to make a “J”. The gasses go up above the heat riser hmthen come down around the bricks and then 15 cm from the bottom they enter the exhaust pipe, so the outside temp reading around the inlet is lower than it would be up higher.
6) so far stone lid is ok. Went up to @ 90 celsius today. We’ll see.
Thanks again.

Gerry Parent wrote:
1) Is the exhaust chimney outside insulated or single wall pipe?
2) Is your bench a bell (hollow chamber) or is it a pipe run?
3) What are the dimensions of your heat riser? It looks really big to me from the photos. Overall dimensions also look off to me. Was your dog house the right size as a form to produce the necessary final dimensions for the core?
4) Is the heat riser insulated? This is the key place where high temperatures are needed to help burn up the wood gasses and produce a clean burn.
5) Can't exactly tell how the flow of gasses proceed beyond the top of the heat riser. Do they travel all around that brick mass or between the firebrick heat riser and metal shell?
6) The stone on top may very well crack and crumble from the intense expansion/contraction experienced over the heat riser if not protected with some insulation.

Finished product:

Hi, just writing to show a rocket mass heater i built, following generally the Minnie by Peter Van den Berg and a little skimming of the RMH book by Ernie and Erica.

Any comments would be helpful as this is a first attempt with virtually now previous knowledge. I’ve probably made some mistakes, but i’m writing this sitting next to the working model, so i suppose not too much got bungled. Had a problem with the riser and it got a little too wide. Also put stone on top, which could expand and blow the whole thing up in a few minutes here, so we’ll see. I lined a cement dog house with fire brick and learned later it was reinforced and had metal inside. Oops. And the masonry work is shoddy, but I’ve never done that before. Here are some pics.
William