Sebastian Köln

+ Follow
since Feb 05, 2016
Sebastian likes ...
cat forest garden solar trees wood heat woodworking
Abkhazia · 400m elevation · temperate climate
Apples and Likes
Total received
In last 30 days
Total given
Total received
Received in last 30 days
Total given
Given in last 30 days
Forums and Threads
Scavenger Hunt
expand Pioneer Scavenger Hunt

Recent posts by Sebastian Köln

I don't see a fixed limit.
As far as water transportation is concerned, at the cellular scale, the physical laws for water as we know it are not quite applicable any more. Effects that are irrelevant at our scale become effective: electrostatic force, friction…
Why would a tree not have a series of pumps? It could also be hollow, evaporate water at the bottom and collect the condensate at the top …

And why would the tree grow that tall?
7 hours ago
Good idea to take an old camera apart (most likely breaking it in the process) to learn how it works. I actually started taking photos on an analog camera. Maybe that is why I still use the manual mode on the modern DLSR.

Aperture / F-Stop: It determines how much light gets through the lens to the film / sensor. light passing through is inversely proportional to the square of the F-number. (twice the F-number -> one quarter of the light)
ISO / Film sensitivity: How strong the sensor / film responds to light. Higher numbers give you a brighter picture, but also more noise / grain.
exposure time: usually specified as fractions of a second. more time (smaller number) -> more light to the film/sensor -> brighter image. (but you have to hold the camera still for that time!)
16 hours ago
I have recently made my second riser out of clay and wood shavings. Just enough clay to make it hold together. Since the humidity is high in Abkhazia, it was put into use before it could dry out. So far looking great.
2 days ago
Disclaimer: I have not build a rammed earth house yet (but am planning on doing so next year), so don't take my words for granted.

Sounds like compressed earth bricks to me. I don't think large sections are a good idea, unless you have a crane to lift them in place. (Normal bricks have a weight that is easy to handle, making them much heavier will likely make handling them exhausting.)
If you only want it for decoration / interior climate, then cob (clay + sand) might be a good alternative. (I have added clay plaster to a quite a few brick walls so far, not too complicated.)
3 days ago
Installing a 100kW hydro power station at the nearby river to provide energy for a handful of local manufactures and 100 people.
6 days ago
One method (have no idea who invented it) is to build the hollow part out of sand (possible a little clay to prevent it from falling apart instantly) and then building on top of that. Once dry, you can shovel/scrape it out.
1 week ago
You can drill a small (5mm-10mm) hole in the barrel to look though. (And seal it with clay if not in use.) That is what I am doing anyway, since I can not buy any high temperature glass here.
1 week ago
In metric units this is pretty easy: 10m of water height ≅ 1bar.
As for pressure loss, there are various calculators online. (one example)

The fun part will be getting pipes that can handle 40bar with plenty of reserve if you are not extremely careful with changes in water flow.
Also, I'd rather not have one burst in the same room as me.
1 week ago
Graham, I don't have fused silica glass here. I looked for glass that tolerates high temperature and stress. Fused silica is pretty much the best you can get. It is used in high-pressure halogen and mercury lamps.
1 week ago
I found a 3.5" by 3.5" Fused Silica plate on Amazon
If you want bigger pieces, you may have to ask the manufacturer.
1 week ago