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Carbon fibres themselves may be corrosion resistent, but the fibers by themselves are like a fabric. If you want a solid part instead of cloth, you need to encase the fibers in a resin. Imagine it like a piece of cloth soaked in beeswax or candle wax: it is solid like the resin but if you pull on it, it has the strength of the fibers of the cloth.

The resins used for carbon fibers are usually very bad at contact with water over long periods of time. Even those in aerospace applications require coating/paint if exposed moisture over time. It’s a plastic, even the best ones don’t do so well in water after a few months.

Furthermore, the damage that moisture does to the resin can be difficult to detect and even more difficult if not impossible to fix. It requires clean rooms, skilled labor and machinery that you don’t have in the middle of an ocean.

Then take iron corrosion: it is easy to spot by naked eye, it may not be easy to repair, but it is relatively simple to “halt” further damage by removing the rust and adding new paint.

Don’t get me wrong: carbon fibers are amazing, but sometimes the “boring” solution is best.

PS: steel alloys and coatings can be amazingly high tech too, it’s amazing what can be engineered.


Cathodic protection is also a nice option against corrosion on stuff that's connected to the grid anyways.


speaking of carbon fiber and immersion, here's a writeup about Titan's use of carbon fiber:

https://www.popularmechanics.com/science/a60687211/titan-sub...


Well, apparently the museum really wants to make sure they have a monopoly on the files, to be able to sell the official copies in their gift shop. No doubt these are of high enough quality that those could be the base of a mould?

Scans of paintings are usually considered public domain, why wouldn’t 3D scans of sculptures be different?


I have made an implementation based on this article before.

https://dyn4j.org/2010/04/gjk-gilbert-johnson-keerthi/

It was years ago but I remember it was the only good ressource I could find that allowed me to understand how it works.


I always imagine that ADHDers would be the gatherers in the hunter-gatherer society. That is where the inattentiveness kicks in. At least for me, when going for a walk,I always notice that I am much more aware of all the plants, flowers, berries and small mammals than my friends. I know that there is a new type of flower I never saw before near that one tree. They actually know where we were on a map.


There is probably not an infinite supply of dna evidence, and testing it is destructive. So I can imagine they don’t want to testany plausible theory but save it for when they are really convinced.


Haha yes, I have been around sewing machines all my life, but my boyfriend always gets so exited to see the inside of the machine and learn about the mechanisms when I need help troubleshooting.

I think that the main thing that I have learned from sewing machines when I was young is daring to open machines and trying to troubleshoot it myself. With these machines a lot ga go wrong but most of it is easy to fix.

Also, I’m not sure how to name it, great 2D to 3D intuition? After a lot of patterns you get great intuition in how you can bend, fold and connect flat shapes to make things in 3D. It is much more commonly applicable than it sounds, and helps me visualize things better.


They haven't shut down, they are selling their prototype and I think they have recently put out a new model.


I feel that where all Aldi’s are relatively comparable, for Edeka it seems to depend a lot on the shop. Where I live there are two Edekas within a 3min drive, one is a bit more fancy than the average Aldi, however the other one has 50 different types of quinoa and people that make you sushi on demand. It is a totally different shopping experience.


I recall that my local Edeka, before Edeka got so big, gave a lot of room to the local managers, who were ex-rocker types who were really good at employing local young dudes who probably weren't all that employable elsewhere (and who did a fine job as it turned out).

Enough that I kind of assumed it was a franchise rather than just a chain, until they started buying up all the Kaisers.

So maybe that's part of their strategy, to give the managers more responsibility to differentiate their stores instead of making them all the same?

If so I wonder how they incentivize that.


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