david higos

https://faroutride.com/condensation-moisture-van/

Apparently according to synthropic farming, pruning sends a growth message not only  to the prunned plants, but to the nearby plants too through the release of plant growth hormone.

Following syntrophic agroforestry biomass plants (that include leguminose ones) should be prunned at the first sign of senescence, before flowering has started. And some roots will die off. (In this case as some roots die I guess nitrogen will be released into the soil in the case these pruned plants are leguminous)

I can't estimate how significant this release will be, but at least I got some explanation

https://www.echocommunity.org/resources/ae1d762e-d561-4a7e-80b3-de9ddeaa6259

hello,

My understanding is that leguminose trees will release the most nitrogen to the soil if they are cut just as they begin flowering.
What would happen if they were pruned extensively? Would they release a lot of nitrogen in this case too?

Hi,

I hope the attachments work this time.

I set the batch alight the 6th of January. It is the day of the year kids tradionally get presents in Spain. So I got mine.

It is not the final version, some shortcuts were taken. It was urgent to set it alight as soon as possible, and make minor ammendments later.  It should be relatively easy to retrofit and integrate benches or   add barrel units on either side.It was very frustrating not being able to use it last winter.

I have struggled to get materials relying on a bicycle for most of the time living in the mountains.

The door is not the final one. No glass has been embedded yet. The handle system will be ammended.

I had been looking for barrels with removable lids for months. Eventually one day I found 6 available. I got them all, and I decided to skip the masonry benches for now. I thought it made things easier and quicker.

The 5 min riser became a few months headache. Unsure about the biopersistency of the fibers I did quite a bit of research and explore many avenues, like asking kilns to make a 2 piece cylinder or  impregnating the interior in kaolin. I cut corners by simply impregnating the ceramic blanket in water glass (made from cat litter and caustic soda) and firing it with a propane torch. I reused a 20 cm pipe to contain the 18 cm riser (23cm exterior diameter). I had to cut the pipe length wise, and stitch it up with metal wire as it became wider than 23 when cut wide open.

The metal plate top of the combustion chamber is only 4mm thick. Aware about the extreme heat close to port zone I placed ceramic blanket in the last section of the combustion chamber underneath the plate, I guess the last 15 cm. This seems to work: this area takes longer to heat up. However, as  the batch had been going on for a couple of hours  partially loaded, and was subsequently fully loaded the plate warped in the middle. To my surprise no smoke came out through the gap left between the ceramic blanket and the plate. The draft was incredibly good, all smoke sucked through the port.
I placed lots of bricks along the raised plate before it had the chance to cool down and it eventually came back to its flat shape. I will weld a thicker plate onto it.

The lower barrel is held tight against the combustion chamber using 4 anchor points, 2 steel ropes and 2 springs to accomodate for the expansion of the metal barrel. I plan to fix the upper barrel to the wall for extrasafety.

No manifold was built it. I think at the moment I am almost 2m2 below maximum ISA of 7.2.

I have built the exhaust at the lowest possible level  and opposite to the combustion chamber, leaving space on both sides to possibly retrofit benches. This was very tedious, I had a very difficult angle/ space to work since the core had already being built and I couldn´t move the walls of the room. To make things harder the brick sizes were just slightly longer than the diameter of the metal pipes/ sections  I was inserting to make the exhaust flue and  I needed some space of clearing to fit ceramic blanket.  

That interphase and the interphases between the barrel and the combustion chamber were quite challenging for this first build. (Fired) water glass helped a lot I feel to rigidise and sort of glue together pieces of ceramic blanket and therefore make reliable interphases.  I was a bit worried to see some smoke through some of these joints in the very first fire, but was very happy no smoke exiting anywhere but the chimney since.

I hope to take a break from this and give some love to my neglected garden.

A video of the making of this batch is being edited and will be shared soon.

I decided to read through  the relevant posts in the forum once again, and I realised the heigth of my benches were lower than recommended. And if I increased these  to the suggested 35 cm (13,7"), the base of the combustion chamber would be below this level, so I am now lifting c.c./riser/barrel.

One of the posts I find most informative is "Batchbox and RMH projet", https://permies.com/t/204327/Batchbox-RMH-projet.

If I understand correcty the recommendation to lift Aurelio's benches was not a matter of seating comfort but to ensure effective stratification. Is this right?  So far I am doing the same to avoid possible malfunctioning (I make them taller as well) although I would like to know I really understand why I am doing it.
I  have spent a few more hours on sketchup. Almost ready yet with these changes.

I would like to be sure I understand what Peter means when he says to Aurelio "the core should be lifted at least up to the level of the bench' ceiling". By the core is he referring to the base of the combustion chamber? Is this a general feature or specifically for that design? Does it help to lift it higher?

I have decided to adapt the technique I saw in a video of the Mallorca build project for the top of the bell (the metal T profiles embedded in ceramic wool) for the top of the combustion chamber ( so I don't need to buy castable refractory or expensive extralarge refractory bricks).  

I plan to introduce a bypass valve somewhere below the barrel/ above the bench ceiling.

Latest sketchup file include the bypass valve.

Any feedback really wellcome.

Thanks for your feedback James. So no metal embedded in cob, got it, different heat expansion properties to that of cob. What you call castable refractory I now understand is called hormigon refractario here, different indeed to refractory mortar.

I attach the latest sketchup file that emphasize the exit path of the smoke towards the chimney. I have tried to clean up the file. Sketchup seems to be a wild creature and there are errors that I don't know how to get rid of. But the important aspect in this drawing is the intended stratification and exit path.

I hope to weld legs to support the flying side of the barrel tomorrow and will be puting the bricks and the cob for real this week.

So anything else I should correct/ do differently pyrofellows?

Hi folks,

I read in a post by Jesse Biggs "8" Batch Box..." about using refractory concrete for the core lid and door.

Big construction shops in Europe like Leroy or BricoDepot sell cheap refractory mortar, rated for 1200C. I haven't found precise technical data for them yet.

It seems if would be the easiest / cheapest materials to make these components (particularly the wide lid). Possibly embedding a metal or fibreglass mesh in it. Do you reckon it would be structurally sound or should I look for some specific refractory mortar?
One of these mortars reads in its specs maximum width layer 20mm, so I thougth about making a 50 cm layer embedding a mesh every 15 cm.  
https://www.leroymerlin.es/productos/marcas/axton/axton-morteros/mortero-refractario-axton-25-kg-gris-81928351.html

Any opinions?

today when I went to the scrapyard I thought of using a metal frame instead of bricks to support the barrel and connect it to the bench with a metal mesh on it to be embedded in cob. Hopefully that could work. I was struggling with the bulkiness of bricks and the gradient problem and it seems I just needed to leave sketchup and go to the scrapyard to get some inspiration...

Hello,

Happy new comfrey.

I have put quite a few hours in the sketchup file. The cavities in the benches are ammended as suggested in the last feedback post.

Rough estimation of ISA is 7,1 m2 (chart critical ISA for 8" system is 7,2m2) and I plan to introduce a manifold/valve before the benches.

I am struggling with the interphase between 1. benches and barrel and 2. benches to chimney.

1. I can´t quite visualise how to build that bench-to-barrel gradient without cement and without limiting the opening of the bottom of the barrel. I am still not happy with my design for this part.

2. I had originally imagined one of the benches-to-chimney passages to go under the core, to make the exit path short and straight. This complicates a bit the ground support of the former.

So far the main idea has been to use ONE wide gate into and out of each bench. No ducts; stratification in hollow benches.

I am willing to consider other options. I am a bit concerned about the pickiness of the stratification systems and my design delay: not sure how much more time I need to sort the design of these interphases.
I also thought of
- sacrificing one of the benches + adding an extrabarrel
- reducing the length of the benches + using an exit gate at the end of them + conecting the bench smoke duct to a duct behind the backseat. If so, I guess it would be better to feed the smoke from barrel to backseat and then as it cools into the bench cavity (I think easier to build, rather than 1st bench 2nd backseat.

I attach the latest sketchup file.

Any suggestions?

Also,
would it be better to get the 5min riser right next to the barrel or should I leave a very little gap as I did in the drawing? (I know smoke won´t run through it) I am a bit unsure how hot it will get on the other side of the ceramic blanket. I guess leaning it against barrel may help slightly help with the stability of the riser and clearing some extraspace in the front.
likewise, is cob a good choice for the triangular sections between riser and the containing brick box?