5 ms·

Honestly for me it falls into "generates a lot of YouTube content, but is of dubious practicality" category. Tesla valve also belongs there. Can someone give ot

Honestly for me it falls into "generates a lot of YouTube content, but is of dubious practicality" category. Tesla valve also belongs there. Can someone give other examples?

slang800 3y ago
Prince Rupert's drop is another.
- andrewflnr 3y ago
  There's no doubt, Prince Rupert's drop is useless. Just neat.
  - defrost 3y ago
    While they're still hot you can press in a pattern along the side (from fat head to long tail), say a lengthy passkey. You now have a physical copy of a passkey that can destroyed in an instant. Neat. Potentially useful.
  - esperent 3y ago
    It's only useless if you consider all art, games, and educational tools to be useless. Which is a very sad outlook. Art: they look beautiful and can be displayed. Game: breaking it, or watching it being broken, is a lot of fun. Education: I would say that a huge number of people have been inspired to take up glassblowing after seeing one of these. But not only that, they also serve as a great tool to demonstrate that an object's physical properties are often unexpected based on appearance. I would say a decent amount of people have been inspired to study physics because of this too.
  - blincoln 3y ago
    Surely there is something interesting that can be done with something that has such unusual properties, even if it's a corner case. It's basically a single-use "transistor" or "valve" for mechanical force. Does the glass explode with enough force to be used as the primary detonator for a high explosive? I'm no explosives engineer, but seems like having an all-mechanical (no chemicals, no electricity) primary detonator could be useful in some situations where the system should be very stable for decades, like car airbags. What about emergency release valves? Plug the release channel with the tough end of the drop. Use a simple mechanical system to break the weak end if the emergency conditions are met. e.g. a lever attached to a float that snaps the weak end if the fluid level is too high. That should work safely even in an environment full of flammable material. Getting into more fanciful territory, could a professional assassin create one that was large enough to work as a hand grenade? Or encase the weak end in a jacket and then use it as a bullet with the tough end being seated in the case?[1] Seems like it could almost be a real-world version of the mythical "ice bullet", where after use there wouldn't be enough left for forensic analysis. [1] Here's a video of someone shooting them from a shotgun, but there's no jacket or spin-stabilization to keep the weak end pointed at the target: https://www.youtube.com/watch?v=lc9pPOrZ_0Q https://www.youtube.com/watch?v=lc9pPOrZ_0Q
deleted 3y ago
[deleted]
explaininjs 3y ago
Haskell. (as someone with published Haskell-based research papers)
- tikhonj 3y ago
  There isn't nearly enough YouTube content about Haskell, unfortunately. I've looked :(
- quchen 3y ago
  As someone who has built a CNC machine by hand and programs it with Haskell I would disagree. (I’ve built lots of other systems, this one is just a very neat showcase of something particularly un-academic.)
  - PostOnce 3y ago
    Hobby? PrintNC? I'll read whatever you feel like typing about it.
anyfactor 3y ago
Torodial propeller
HideousKojima 3y ago
Elephant toothpaste?
richk449 3y ago
Farnsworth fusor
- Baeocystin 3y ago
  You're completely right, but I want to build one so bad! It's up there with Jacob's Ladders as the most Sciency thing I can think of, in terms of visual effect.
- askvictor 3y ago
  And I assumed this was a Futurama reference...
the_shivers 3y ago
Nixie tubes.
postalrat 3y ago
New rust projects
kragen 3y ago
maybe if there was youtube 100 years ago, in the category of 'generates a lot of YouTube content, but is of dubious practicality', we'd list - so-called "monoplanes" with only a single pair of wings (if not airplanes in general), - "wireless" broadcasting (if not radio communication in general), - x-rays, - "battery eliminators" (dc power supplies you plugged into the wall so you could run a radio without batteries, introduced commercially two years later), - arc welding, - air conditioners, - electric cars, - diesel ships, - small motorboats, - electronic music, - hydraulic excavation equipment, - electrical intercom systems, - electrical door locks permitting you to buzz someone into your building, - buses with indoor seats, - phonograph records with more than four minutes of music per side, - light meters for photography, - the manufacture of ice (as opposed to sawing it from frozen rivers and lakes in winter), - parking lots with parking spots outlined with angled lines to permit easy parking, - cranes with endless-tread tracks, - diesel locomotives, - bulletproof vests, - water slides, - particle board, - drive-in restaurants, - automatic corking machines for bottling plants, - motor homes, - motor-operated electrical switches, - aerial photography, - metal ladders as light as wooden ones, and - toothpaste. oh and also tesla valves most of these came from https://ia601306.us.archive.org/31/items/PopularMechanics1923/Popular_Mechanics_01_1923.pdf https://ia601306.us.archive.org/31/items/PopularMechanics192...
digdugdirk 3y ago
Whoa there. Even as someone who spends only a small amount of time in a shop, a fractal vise is way more "everyday" useful than a tesla valve, or any of the things posted as a reply. The most common methods of keeping something in place to be drilled/machined require at least one flat face in order to perform the clamping, or else extremely expensive and time consuming custom made fixtures. A fractal vise would perform an adequate job for a wide array of hobbyist level tasks. Even at ~$3000, it would pay for itself after a handful of jobs just from the lack of fixturing costs alone.
- blagie 3y ago
  As a hobbyist, at $3000, I can say this would not pay for itself. I'd absolutely love to have one, but for hobbyist use, it would need to be O($100). I think the real innovation would be to bring this from O($3000) to O($100). I actually think that's possible. There's a 3d-printed version which wouldn't be strong enough, but looking at this, what I think would be needed would be: 1. Simple metal disks, with holes drilled, cut in half. These could be economically made on a waterjet, or more economically, by slicing an extruded pipe into disks, drilling those disks with holes for more disks, and cutting them in half, as well as a top and bottom plate. 2. Plastic (3d printed or, in quantity, injection molded) fixtures to keep it together. 3. A classical vise (this could even be an insert) The design in my head would have the metal pieces take 100% of the force when this is being used as a vise. However, instead of the complex metal machining to keep this thing fitting together, it would use cheap plastic pieces. Most hobbyist can afford 0-2 tools in the O($3000) range, and while useful, this doesn't compete with having e.g. a high-quality welder, a mill, or a lathe. Another homebrew design I found on a quick web search: https://hackaday.com/2021/07/10/fractal-vise-holds-odd-shaped-objects-tight/ https://hackaday.com/2021/07/10/fractal-vise-holds-odd-shape...
- jdietrich 3y ago
  A fractal vise is largely a gimmick. The biggest problem we encounter with vises is the phenomenon of jaw lift. There will always be some amount of play between the moveable jaws and the base of the vise, there will always be some amount of deflection, so applying clamping forces tends to force the vise jaws apart in a v-angle rather than the jaws remaining strictly parallel. This causes problems with repeatability and reduces maximum clamping force, because the clamping force is pushing the part up and out of the vise. A lot of engineering effort goes into minimising and mitigating jaw lift. A fractal vise will always be more susceptible to jaw lift, because the play between those recursive segments will add together. Each segment might only be slightly out of square when under clamping force, but that adds up to a large parallelism error at the clamping faces. The practical alternative for milling would be something like an Adaptix vise, which uses multiple sliding and locking fingers to allow the clamping faces to adapt to a non-parallel part. Other alternatives would include 3D-printed soft jaws, soft jaws molded with a low-Tg polymer like polycaprolactone, or an adhesive workholding system like Blue Photon. https://www.norgrenworkholding.com/en https://www.norgrenworkholding.com/en
astrange 3y ago
Hot dog electrocuters https://youtu.be/tcqiNn8RNrk https://youtu.be/tcqiNn8RNrk
kklisura 3y ago
Tensegrity table or chair.

Honestly for me it falls into "generates a lot of YouTube content, but is of dubious practicality" category. Tesla valve also belongs there. Can someone give other examples?

slang800 3y ago

Prince Rupert's drop is another.

andrewflnr 3y ago
There's no doubt, Prince Rupert's drop is useless. Just neat.
- defrost 3y ago
  While they're still hot you can press in a pattern along the side (from fat head to long tail), say a lengthy passkey. You now have a physical copy of a passkey that can destroyed in an instant. Neat. Potentially useful.
- esperent 3y ago
  It's only useless if you consider all art, games, and educational tools to be useless. Which is a very sad outlook. Art: they look beautiful and can be displayed. Game: breaking it, or watching it being broken, is a lot of fun. Education: I would say that a huge number of people have been inspired to take up glassblowing after seeing one of these. But not only that, they also serve as a great tool to demonstrate that an object's physical properties are often unexpected based on appearance. I would say a decent amount of people have been inspired to study physics because of this too.
- blincoln 3y ago
  Surely there is something interesting that can be done with something that has such unusual properties, even if it's a corner case. It's basically a single-use "transistor" or "valve" for mechanical force. Does the glass explode with enough force to be used as the primary detonator for a high explosive? I'm no explosives engineer, but seems like having an all-mechanical (no chemicals, no electricity) primary detonator could be useful in some situations where the system should be very stable for decades, like car airbags. What about emergency release valves? Plug the release channel with the tough end of the drop. Use a simple mechanical system to break the weak end if the emergency conditions are met. e.g. a lever attached to a float that snaps the weak end if the fluid level is too high. That should work safely even in an environment full of flammable material. Getting into more fanciful territory, could a professional assassin create one that was large enough to work as a hand grenade? Or encase the weak end in a jacket and then use it as a bullet with the tough end being seated in the case?[1] Seems like it could almost be a real-world version of the mythical "ice bullet", where after use there wouldn't be enough left for forensic analysis. [1] Here's a video of someone shooting them from a shotgun, but there's no jacket or spin-stabilization to keep the weak end pointed at the target: https://www.youtube.com/watch?v=lc9pPOrZ_0Q https://www.youtube.com/watch?v=lc9pPOrZ_0Q

deleted 3y ago

[deleted]

explaininjs 3y ago

Haskell. (as someone with published Haskell-based research papers)

tikhonj 3y ago
There isn't nearly enough YouTube content about Haskell, unfortunately. I've looked :(
quchen 3y ago
As someone who has built a CNC machine by hand and programs it with Haskell I would disagree. (I’ve built lots of other systems, this one is just a very neat showcase of something particularly un-academic.)
- PostOnce 3y ago
  Hobby? PrintNC? I'll read whatever you feel like typing about it.

anyfactor 3y ago

Torodial propeller

HideousKojima 3y ago

Elephant toothpaste?

richk449 3y ago

Farnsworth fusor

Baeocystin 3y ago
You're completely right, but I want to build one so bad! It's up there with Jacob's Ladders as the most Sciency thing I can think of, in terms of visual effect.
askvictor 3y ago
And I assumed this was a Futurama reference...

the_shivers 3y ago

Nixie tubes.

postalrat 3y ago

New rust projects

kragen 3y ago

maybe if there was youtube 100 years ago, in the category of 'generates a lot of YouTube content, but is of dubious practicality', we'd list - so-called "monoplanes" with only a single pair of wings (if not airplanes in general), - "wireless" broadcasting (if not radio communication in general), - x-rays, - "battery eliminators" (dc power supplies you plugged into the wall so you could run a radio without batteries, introduced commercially two years later), - arc welding, - air conditioners, - electric cars, - diesel ships, - small motorboats, - electronic music, - hydraulic excavation equipment, - electrical intercom systems, - electrical door locks permitting you to buzz someone into your building, - buses with indoor seats, - phonograph records with more than four minutes of music per side, - light meters for photography, - the manufacture of ice (as opposed to sawing it from frozen rivers and lakes in winter), - parking lots with parking spots outlined with angled lines to permit easy parking, - cranes with endless-tread tracks, - diesel locomotives, - bulletproof vests, - water slides, - particle board, - drive-in restaurants, - automatic corking machines for bottling plants, - motor homes, - motor-operated electrical switches, - aerial photography, - metal ladders as light as wooden ones, and - toothpaste. oh and also tesla valves most of these came from https://ia601306.us.archive.org/31/items/PopularMechanics1923/Popular_Mechanics_01_1923.pdf https://ia601306.us.archive.org/31/items/PopularMechanics192...

digdugdirk 3y ago

Whoa there. Even as someone who spends only a small amount of time in a shop, a fractal vise is way more "everyday" useful than a tesla valve, or any of the things posted as a reply. The most common methods of keeping something in place to be drilled/machined require at least one flat face in order to perform the clamping, or else extremely expensive and time consuming custom made fixtures. A fractal vise would perform an adequate job for a wide array of hobbyist level tasks. Even at ~$3000, it would pay for itself after a handful of jobs just from the lack of fixturing costs alone.

blagie 3y ago
As a hobbyist, at $3000, I can say this would not pay for itself. I'd absolutely love to have one, but for hobbyist use, it would need to be O($100). I think the real innovation would be to bring this from O($3000) to O($100). I actually think that's possible. There's a 3d-printed version which wouldn't be strong enough, but looking at this, what I think would be needed would be: 1. Simple metal disks, with holes drilled, cut in half. These could be economically made on a waterjet, or more economically, by slicing an extruded pipe into disks, drilling those disks with holes for more disks, and cutting them in half, as well as a top and bottom plate. 2. Plastic (3d printed or, in quantity, injection molded) fixtures to keep it together. 3. A classical vise (this could even be an insert) The design in my head would have the metal pieces take 100% of the force when this is being used as a vise. However, instead of the complex metal machining to keep this thing fitting together, it would use cheap plastic pieces. Most hobbyist can afford 0-2 tools in the O($3000) range, and while useful, this doesn't compete with having e.g. a high-quality welder, a mill, or a lathe. Another homebrew design I found on a quick web search: https://hackaday.com/2021/07/10/fractal-vise-holds-odd-shaped-objects-tight/ https://hackaday.com/2021/07/10/fractal-vise-holds-odd-shape...
jdietrich 3y ago
A fractal vise is largely a gimmick. The biggest problem we encounter with vises is the phenomenon of jaw lift. There will always be some amount of play between the moveable jaws and the base of the vise, there will always be some amount of deflection, so applying clamping forces tends to force the vise jaws apart in a v-angle rather than the jaws remaining strictly parallel. This causes problems with repeatability and reduces maximum clamping force, because the clamping force is pushing the part up and out of the vise. A lot of engineering effort goes into minimising and mitigating jaw lift. A fractal vise will always be more susceptible to jaw lift, because the play between those recursive segments will add together. Each segment might only be slightly out of square when under clamping force, but that adds up to a large parallelism error at the clamping faces. The practical alternative for milling would be something like an Adaptix vise, which uses multiple sliding and locking fingers to allow the clamping faces to adapt to a non-parallel part. Other alternatives would include 3D-printed soft jaws, soft jaws molded with a low-Tg polymer like polycaprolactone, or an adhesive workholding system like Blue Photon. https://www.norgrenworkholding.com/en https://www.norgrenworkholding.com/en

astrange 3y ago

Hot dog electrocuters https://youtu.be/tcqiNn8RNrk https://youtu.be/tcqiNn8RNrk

kklisura 3y ago

Tensegrity table or chair.