I always enjoy seeing one of my videos on HN! Let me know if you have questions.
pierrekin 36 minutes ago [-]
Not strictly related to this video - sorry about that - but I have some ideas of how to improve the system you used to record arc welding in high quality.
Do you still have the hardware? Does revisiting the project and using some signal processing to try and extract color images sound like fun? I would be excited to collaborate on this if you had energy for it!
kragen 58 minutes ago [-]
My bookmark from May 28 says:
https://www.youtube.com/watch?v=M6XIgdS1rzs #Applied-Science #video on #bootstrapping “insanely powerful” planetary ball mill grinder to make α'' iron nitride filled epoxy for magnets, which did work somewhat; he tested it in a 1.6-tesla vibrating sample magnetometer he built using a lock-in amplifier to plot its B–H curve.
Hopefully this summary is useful to others.
On the topic of alternatives to rare-earth magnets, their most important use is probably electrical machines (motors/generators, and switched reluctance electrical machines can supposedly have power densities comparable to rare-earth-magnet permanent-magnet electrical machines, and you can build them out of just punched electrical steel, copper or aluminum wire, and insulator, just like a line-frequency power transformer. (I suspect Metglas would work better than electrical steel, without requiring any strategic materials, but might be impractically expensive.) Some relevant bookmarks from September 22:
https://www.youtube.com/watch?v=vvw6k4ppUZU #video about "SynRM" switched reluctance motors made out of sheets with slots punched out to follow field lines. Low-quality AI voiceover from #Lesics.
(You can actually build SRMs out of non-laminated mild steel and speaker wire or whatever, but they won't be efficient.)
lokimedes 9 hours ago [-]
I love this guy. Totally living out my physicist-tinker dreams.
showmexyz 1 hours ago [-]
His videos/experiments are really really good.
Some of other good videos-
The fact they don't have a 'buy one of our magnets now, $10' button tells me that the tech doesn't actually work.
ralphonzathew 2 hours ago [-]
Iron nitride is much more useful as a thin film coating. Bulk magnet tech just isn't there.
scythe 2 hours ago [-]
The only report of a bulk Fe16N2 magnet I remember reading about used a 2 GPa (300 kpsi) diamond anvil to compact the powder. I can see why that might be economically impractical right now.
Also there was a bombshell paper that came out claiming synthesis of bulk L10-FeNi which was later retracted [1] and may have put a temporary damper on interest in Fe16N2. It remains unclear which material will be available first.
good luck getting ammonium nitrate without being visited by the police (at least here in Europe)
nancyminusone 1 hours ago [-]
What does your country use for its instant cold packs?
impossiblefork 6 hours ago [-]
Farmers work with hundred kilo bags of the stuff.
wolfi1 5 hours ago [-]
farmers yes, I wanted to cool some stuff with it, no chance
impossiblefork 3 hours ago [-]
and you can't just buy it for your garden then?
numpad0 2 hours ago [-]
Fertilizers and a ball mill in a garage is just the classic direct highway route from nothing to pipe bombs, so there are going to be checkpoints along the way.
metalman 6 hours ago [-]
not that big a deal, but you do have to register and have basic security, ammonium nitrate is by todays standards just one step up from black powder, and if it's a proper company with mechanical and chemical engineers signing off then it's literaly just paper work.All in all industrial type experimenting involves avoiding exuberant exothermic reactions and dramatic kinetic events, with or without an electrical component, just about everyone involved has a story, and there are plenty of injuries and fatalities.
One of the hard parts of bootstraping any industrial process is having people who have the knowledge and experience to train people in how to do things and not get hurt, it's not "saftey" as much as survival skills.
HeyLaughingBoy 1 hours ago [-]
> ammonium nitrate is by todays standards just one step up from black powder
I thought that was potassium nitrate. Which I bought a bottle of on Amazon when I was curing a ham.
Calwestjobs 9 hours ago [-]
yeah, but point is more like that we do not need hard to refine ( that is why are they called rare earths ) materials from china, if those magnets were strong as neodymium ones. which they are not in video.
--
problem with chemistry is most of these things are easily made in garage.
For example Slovak military is training disposal of homemade explosives / chemicals by watching NurdRage videos ;)
Do you still have the hardware? Does revisiting the project and using some signal processing to try and extract color images sound like fun? I would be excited to collaborate on this if you had energy for it!
https://www.youtube.com/watch?v=M6XIgdS1rzs #Applied-Science #video on #bootstrapping “insanely powerful” planetary ball mill grinder to make α'' iron nitride filled epoxy for magnets, which did work somewhat; he tested it in a 1.6-tesla vibrating sample magnetometer he built using a lock-in amplifier to plot its B–H curve.
Hopefully this summary is useful to others.
On the topic of alternatives to rare-earth magnets, their most important use is probably electrical machines (motors/generators, and switched reluctance electrical machines can supposedly have power densities comparable to rare-earth-magnet permanent-magnet electrical machines, and you can build them out of just punched electrical steel, copper or aluminum wire, and insulator, just like a line-frequency power transformer. (I suspect Metglas would work better than electrical steel, without requiring any strategic materials, but might be impractically expensive.) Some relevant bookmarks from September 22:
https://www.youtube.com/watch?v=TAhF45AtsgA #video by #Akio showing his Arduino-driven switched reluctance motor #electronics control board and working motor #hardware
https://www.youtube.com/watch?v=vvw6k4ppUZU #video about "SynRM" switched reluctance motors made out of sheets with slots punched out to follow field lines. Low-quality AI voiceover from #Lesics.
(You can actually build SRMs out of non-laminated mild steel and speaker wire or whatever, but they won't be efficient.)
https://www.youtube.com/watch?v=UIqhpxul_og
https://www.youtube.com/watch?v=bR9EN3kUlfg
https://www.youtube.com/watch?v=Oj4tRnLKN6U
[1] https://www.nironmagnetics.com/
Also there was a bombshell paper that came out claiming synthesis of bulk L10-FeNi which was later retracted [1] and may have put a temporary damper on interest in Fe16N2. It remains unclear which material will be available first.
1: https://advanced.onlinelibrary.wiley.com/doi/full/10.1002/ad...
https://news.ycombinator.com/item?id=42995429
I thought that was potassium nitrate. Which I bought a bottle of on Amazon when I was curing a ham.
--
problem with chemistry is most of these things are easily made in garage.
For example Slovak military is training disposal of homemade explosives / chemicals by watching NurdRage videos ;)
https://youtu.be/Zybj-mi1FP0?si=KGMUJj5l5NUt2egh&t=68
or this simple technology from 1890 used in different way is helping helping Europe to be self sufficient with energy:
https://www.tue.nl/en/research/institutes/eindhoven-institut...