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?
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.
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-shape...
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.
Regardless, I'm a little shocked that a) I've never seen either of these designs manufactured by low-cost brands like Harbor Freight, and b) the ones that are out there are so expensive. A complete Adaptix vice setup is $7000? I'm sure that makes sense for professional machinists or people working with a LOT of force, but surely a hobbyist version could be made for a sale price less than $100, maybe $200 for a heavy-duty version. It's basically just a big vice that has two smaller, perpendicular vices for its jaws, and the smaller vices have captive, sliding metal bars between their jaws, right? I'm pretty sure I could make a set of jaws that would suit my purposes out of parts that would cost no more than $25 at the hardware store. It would have saved me an awful lot of headache on small hobby projects over the years, so I'm probably just going to go ahead and hack one together.
Either of the fractal designs (classic "teeth at the ends" version versus "flat-faced", for lack of better names) seem like they would require a decent amount of fairly precise machining, so I can understand them costing more, but $2000 for an Ali Express version still seems high.
You now have a physical copy of a passkey that can destroyed in an instant.
Neat. Potentially useful.
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.
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
- 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/PopularMechanics192...