Very delicate work.

The escapement of a watch lets the mainspring power the movement while keeping relatively constant time over the range of the spring. It does this with a balance wheel that oscillates at a certain frequency. However, if you change the orientation of the balance wheel with respect to gravity, you can affect the frequency, so the tourbillon rotates the balance wheel around 3 axes so the errors cancel each other out on average.

Really, though, the true purpose of a tourbillon is to showcase the watchmaker's prowess, since a cheap quartz watch will keep more accurate time than even very high end mechanical watches. So it's mostly about aesthetics.

The rotating contraption is called a tourbillon. It helps a mechanical wristwatch keep time despite being moved around and held at different angles.

What is this exactly?

Also: a quality tourbillon from a respected watchmaker is extremely expensive, and therefore a status symbol.

Chainless Bicycle

Chainless Bicycle

This is ridiculous. With a normal chain and cassette you're spreading the pedaling force over numerous teeth. With this you're concentrating all the force on one tooth and one bearing.

I know what a chain and sprocket can do to my pants. I hesitate to think what this thing could do to my leg.

No because the gears are made of unobtanium.

oof that looks like it can't handle any torque at all.

Rocket propulsion hovering

back when TLC was worth a shit.

I'm now conditioned to expect someone to hit it with a hockey stick.

What, where was this done?

At the National Hover Test Facility at Edwards Air Force Base, California:


It doesn't just gravity well, it gravities brilliantly.


There's so much stuff going around at once. My brain can't keep track of it all

A+ marble maze C– camera work

Peristaltic (contract-relax) motion robot

After a few weeks, it forms a cocoon and emerges as a V-22 Osprey

so could you line the inside with some sort of latex?

Human imagination is so impressive, either that or someone had a nightmare and decided to build it.

It mimics the movement of our digestive systems.

Nakamichi RX-202 Two Head Auto Reverse Stereo Cassette Deck (1982)

For those wondering why:

Cassette tape is actually capable of some pretty outstanding audio quality with the right equipment and setup, but a big factor is the kind of tape head and how well the it is aligned with the tape. Most tape players just had a head that could read in both directions, but that wasn't the ideal way to do it because single direction heads were higher quality. Some companies would use a single direction head that actually flipped 180°, but then the alignment issue comes into play because a head that moves will never be as precise as one that's fixed in place.

Enter this design. Instead of trying to design a high-quality player that could reverse direction they just built a single-direction tape player and gave it a way to flip the tape itself. I think a few different companies experimented with this type of solution in the 1970s-1980s, but this one was definitely the most famous. By the 1990s when the highest quality cassette decks were being manufactured it seems like everyone had given up and switched to normal reversing decks, but I don't know if that was because they had fixed the problems or just because it was easier to design/build.

Isn’t it crazy that they engineered that entire set up, rather then flip the read/write head.

Nakamichi was the shit back in the day.

It will last a long time in storage, but only if it isn’t used. It’s a very mechanical process, and he action of reading and writing causes wear and tear.

If left alone it’ll last hundreds of years. Stable.

If used constantly, it’ll degrade quickly. Not durable.

Magnetic tape is an excellent durable storage medium. Pretty much every tech company will still be running magnetic tape backups of their servers, that's why it took Google two days to restore thousands of email inboxes after they were accidentally deleted a few years back, they had to play the tape back and copy the data back off.

Sterling Hot Air Engine in Action

Sterling Hot Air Engine in Action

ELI5? Not sure what's going on here, bud definitely looks cool.

Look up the Stirling Engine.

I wouldn't describe it as a "hot air engine" so much as a "differential temperature engine".

Basically if you can get one of the plates at a significantly different temperature from the other that differential powers the piston. (The side that's warmer will determine which direction the engine spins) Most desktop models use a little tea light/candle to warm one of the plates but this could also be done with one plate buried in snow/ice and the other exposed to warmer atmosphere.

And then the engine runs a generator to run the datacenter.

Boom! Endless energy!

Well, it’s cool on one side, and hot on another

Carving stars

Carving stars

What’s the name of that kind of bit?

three-axis tourbillon

three-axis tourbillon

This one is an upscaled model to show how it works. Really tiny ones are used in mechanical watches, the idea being to average out precision errors due to the effects of gravity on the mechanism.


In horology, a tourbillon (; French: [tuʁbijɔ̃] "whirlwind") is an addition to the mechanics of a watch escapement. Developed around 1795 and patented by the French-Swiss watchmaker Abraham-Louis Breguet on June 26, 1801, a tourbillon aims to counter the effects of gravity by mounting the escapement and balance wheel in a rotating cage, to negate the effect of gravity when the timepiece (thus the escapement) is stuck in a certain position. By continuously rotating the entire balance wheel/escapement assembly at a slow rate (typically about one revolution per minute), the tourbillon averages out positional errors.

Originally an attempt to improve accuracy, tourbillons are still included in some expensive modern watches as a novelty and demonstration of watchmaking virtuosity.

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What would something like this be used for?

This mp4 version is 81.25% smaller than the gif (458.17 KB vs 2.39 MB). The webm version is even 94.08% smaller (144.6 KB).

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Porsche Panamera Wing

Porsche Panamera Wing

For when you need to go over 35mph.

If you can drive fast enough it will provide downforce which gives you more grip which lets you corner faster. So in short; it's purely cosmetic for anyone not doing track days.

It annoys me that they didn't just do one take to make it a perfect loop

Does it serve a practical end or is it purely cosmetic?

Try one of these subthreads