I've been messing with #infrared #photography using #termux #dcraw & #imagemagick to process RAW files without needing a computer.
There are examples, instructions & the scripts, in mobile friendly chunks, on my #selfhosted website, & the basics are on github too (https://github.com/Linecutterx/PhotoScript) More examples at https://www.macklin.co/infrared-photography-0/
The sheath deals with that. Friction/screw tension makes it harder too. You're right though, there is no lock to keep it closed if it's not enclosed somehow.
You can change quite a lot (pivot & blade are original)
That's the speed of lightning in a vacuum, the speed of lightning in a dojo is significantly slower. In fact scientists believe that it can be brought to a crawl visible to normal human vision using a Tai Chi doping process. (Vacuum: Yes, i know)
Wow, that's a big 3d printer! (If you've ever printed spaghetti on a smaller 3d printer then you know)