This is insanely cool, the noise they make is also really satisfying!
What was the cost/time breakdown of the entire project because the flipdisc prices are hidden behind quotes and it seems like it would take quite a lot of time to complete the whole display!
sen•Apr 27, 2026
The prices I’ve seen mentioned are around USD$3-5 per “pixel”.
Similar to all the ePaper projects that show up here, they’re expensive but cool gimmicks.
londons_explore•Apr 27, 2026
Whole dollars per pixel is insane!
The whole mechanism looks very 3d printable... I wonder if one could design one with PCB coils and a large 3d print only? If so, cost could probably come down to cents per pixel...
You'd probably also need a single 'C' shaped piece of steel for the magnetic flux path, but you might be able to find a supplier for the right shape already used for something else you can buy in large quantities very cheaply (eg. Steel staples).
nottorp•Apr 27, 2026
These mention 25-30 fps, so the mechanism may cost a bit to be that sturdy.
I wonder if anyone makes cheaper versions that you're only supposed to update at 1 frame per minute or less...
harikb•Apr 27, 2026
Is the last photo on that page, describing the cabling, a screenshot of another photo displayed using flipdiscs? that is a whole lot of discs!!
razorbeamz•Apr 27, 2026
I think it's just a simulation of what it could look like if it were flipdiscs.
ofrzeta•Apr 27, 2026
I bought a flip dot display on eBay and now I am stuck with the old thing and my lack of knowledge to make it work. Here's a great resource about technical details (only German though) https://radow.org/flip-dot.php
EDIT: "They have high readability, a long lifespan, and achieves anywhere between 25-60fps" - I think you can't achieve 60fps with a flip dot display.
londons_explore•Apr 27, 2026
Depends how much power and noise you're willing for it to make!!
Remember that texas instruments DLP technology which is in use in pretty much every office/home cinema projector is effectively micro flip-dots micromachined in silicon, and that can operate at ~10,000 FPS.
ofrzeta•Apr 27, 2026
With my rudimentary physics knowledge I'd think that smaller structures can be moved faster than bigger structures.
EDIT: also when you google a bit you can find a guy who maxed out flip dot displays at 30fps (which honestly I thought would not be possible either)
IshKebab•Apr 27, 2026
Uhm yeah they are a lot smaller. That makes a difference obviously.
alnwlsn•Apr 27, 2026
They can't if they are wired like they usually are from the factory, because they are wired in a matrix where you can only update one row at a time. They did this to save on IO lines/output transistors, I guess. So you have to wait for the whole screen to finish drawing before beginning the next frame.
But you can flip them fast/in parallel if you have a driver for each disc:
I've been working on one and I have and I am trying to use an H-bridge per disc. It's possible to find very cheap ICs; for my 308 discs, it only cost $10 for these (not counting the additional time/costs that comes with coming up with 616 IO lines, getting a PCB made, dealing with power issues, etc):
They've been slowly replacing the flip-disc displays on the buses where I live with LEDs and LCD panels which has been such a shame. There is a beautiful mechanical satisfaction to a panel of flip-discs inverting and I genuinely find them easier to read.
sschueller•Apr 27, 2026
Yes, even the ones that have an LED behind each disk which are on in the dark. This display [1] is the same but in the dark [2] you see the LEDs instead.
The LED / LCD displays are probably lighter (less heavy), and someone figured they can save 0.001 gallons of diesel a year fleet wide if they replace displays.
Net Zero Fatigue is real.
pastel8739•Apr 27, 2026
Much more likely, I think, the mechanical displays had some maintenance cost which cheap LED displays will not.
Rodeoclash•Apr 27, 2026
You've confabulated a reason why they replaced them, linked it to initiative then complained about them doing it all in two sentences. A gold medal in mental gymnastics is warranted here!
MrBuddyCasino•Apr 27, 2026
They’re probably just cheaper and require less maintenance.
You’re not doing your cause any favors by projecting everything on an ill-fitting frame.
Gigachad•Apr 27, 2026
They seemed less reliable than LEDs. When they were common here they would always have tens of dots stuck in the wrong position.
Perz1val•Apr 27, 2026
I'd imagine the vibrations didn't do them any good
OuterVale•Apr 27, 2026
Interestingly, I've never noticed any stuck discs. I'm pretty observant of them as well, because I think they're so cool.
Gigachad•Apr 27, 2026
The ones here could have been nearing the end of their life to be fair. They have basically all been replaced with LED signs now.
xattt•Apr 27, 2026
The Luminator MAX 3000 is an interesting hybrid between a flip dot display and an LED display. I find it very pleasing to the eye and easy to read, particularly at night.
In front of the flip dots is a frame that has a mini-LED that faces and front-lights each flip dot. This gives the appearance that each flip dot is glowing.
You made me wonder just how often Touhou is even mentioned on HN, so I did a quick search and... less than 15 results! (not counting dupes).
Niche indeed...
mghackerlady•Apr 27, 2026
That seems weird. Bad Apple is up there with doom in terms of "make it run", and a few high profile-ish hackers seem to enjoy touhou stuff (drew devault off the top of my head)
There’s a very large one of these at “Climate Pledge Arena” in Seattle. Perhaps 8 feet tall and 16 feet wide. Pretty cool, but stuck pixels are even more annoying when it makes you want to reach out and poke them.
I use quotes because it will always be the Colosseum to me, where I saw the Butthole Surfers, Dead Moon and Nirvana. Don’t get me started on the Kingdome.
Brendinooo•Apr 27, 2026
That arena famously has dead pixels on its video boards hanging over the ice as well!
nandomrumber•Apr 27, 2026
That display needs some Conway’s Game of Life action pronto.
test1235•Apr 27, 2026
they have a gif at the bottom of the article which looks like game of life
Dunno where your link is going, but yeah I see the gif at the bottom of the article now.
Still, I wanna see and hear it on the display.
einpoklum•Apr 27, 2026
I have a question about those wire ferrules they said they were using:
I occasionally connect wires to terminals, but - I've never used ferrules: I just self-twist the thin strands, push the thing in, and use the lever or tightening screw depending on the terminal's mechanism.
Why would I use a ferrule? Or perhaps, under what circumstances is that advised?
Ferrules often have insulating shells around the base which are good strain relief.
Ferrules also evenly distribute the clamping force and prevent crushing of the strands.
Ferrules solve the problem of having to align the threads every time you re-post them in a terminal block.
orangewindies•Apr 27, 2026
The wire will crush over time and the connection will become looser. That will increase the resistance of the connection and in high current applications will cause heating. If you're really unlucky it will cause a fire.
polyterative•Apr 27, 2026
Technology is so cool and you're using it to build a mirror. Would have loved to see generative or other weird graphics.
bovermyer•Apr 27, 2026
Did you read the article? The author goes into several applications beyond just that.
simonjgreen•Apr 27, 2026
There is a fairly impressive installation of these at Heathrow airport in Terminal 5 outside the BA lounges. Struggling to find a decent video on YouTube, but this one’s not terrible https://youtu.be/G03WA30yFMI?si=hx5aLlrj_BH21yr2
divbzero•Apr 27, 2026
The Climate Pledge Arena in Seattle has an installation too:
I remember seeing those at the airport when I was a kid it was fascinating, one of the screens was close to the ground and I got over the chairs just curious how do they flip, now we have the boring soulless LEDs.
Last I heard a number of years ago it’s around $2000/sq ft. Around the same price scale as mid range LED wall modules.
rendaw•Apr 27, 2026
> "Oceans" is a kinetic sculpture that embodies the dynamism of the world's oceans within the arid landscape of Las Vegas. Crafted from 483 motorized elements known as "Brixels," this piece mimics the movement of the sea's surface. The sculpture is alive with the pulse of the planet's waters, ...
All I can see are bars of gold.
mcphage•Apr 27, 2026
I agree... it's gorgeous, but it's missing the ocean's colors.
breakfastny•Apr 27, 2026
BREAKFAST (AKA Zolty) here. The “ocean” aspect of the piece is in how it moves and the real-time API data that drives the wave-like motion. It grabs live tide data from a different coastal city each minute and changes based on that. The gold and marble bricks took inspiration from the Fontainebleau art deco style of their original Miami hotel (this piece lives in their Vegas location).
Interesting, that "fade away" effect looks almost exactly like what I see when I get a migraine aura.
b800h•Apr 27, 2026
Popular in UK train stations until very recently. I suspect that there are still a few out there!
bovermyer•Apr 27, 2026
The author mentions SubSpace (the computer game, from the 90s), and the limited pixel budget for player banners in it.
It would be interesting to see if you could run a pared-down version of that game on a display like this.
jimnotgym•Apr 27, 2026
Lookmumnocomputer did some nice work for thismuseumisnotobsolete with flip displays.
See on YouTube or visit in person
grishka•Apr 27, 2026
If you're into electromechanical machines, he also has a working telephone exchange and a bunch of videos where he restores its various components and explains how it works (I still don't quite understand how it works though). That's the original reason I subscribed to his channel, but his wild musical contraptions are also cool.
po1nt•Apr 27, 2026
I would love to see the cost of the whole hardware mentioned. I guess it would be around a 1000USD
soblemprolver•Apr 27, 2026
It is so sad to see both this and the title "It's ok to abandon your side project" on the front page while I have three flipdisc displays sitting in the basement without the time and equipment to get them up and running.
No, it's not ok to abandon those flipdisc displays! :(
Admittedly I read neither of the articles. But who doesn't sometimes get caught up in the conincidence of titles on here may vote me down :D
whynotmaybe•Apr 27, 2026
Unless you've thrown everything away, your side project isn't abandoned, it's reprioritized.
alnwlsn•Apr 27, 2026
You'll get to it when you get to it. After 2 years, I've just been working on my flipdiscs this weekend!
abhiraj_patwa•Apr 27, 2026
It's crazy that I was trying to find good resources for split flaps and then flip discs just yesterday and was just thinking, damn, there aren't any good or recent information about flip discs, just decade-old proprietary stuff to be found
Great work!
ricardobeat•Apr 27, 2026
If I’m not mistaken (their pricing is a bit hard to find), nine of the flip fits display modules will set you back ~$5000 alone, plus the rest of the hardware. While I love the idea that is a lot of fun budget for other projects…
stavros•Apr 27, 2026
Thanks, I've been looking for that. Interesting how nowadays it's orders of magnitude cheaper to buy a 4k 65" panel and fake the dots (and sound) on it.
mhb•Apr 27, 2026
I recall a comment from somewhere that it was cheaper to put up a large monitor over a hole in the wall than to pay someone to patch it...
stavros•Apr 27, 2026
Haha, that actually sounds plausible, but, since monitors are backlit, your hole will be glowing.
Nobody outside a gas station wants a glowy hole.
rayiner•Apr 27, 2026
You can put an OLED TV over a hole in the wall and it's cheaper than getting someone to fix the drywall.
laserbeam•Apr 27, 2026
Damn, I really wish there was a T in "Quick jazzy vibe flows from exploding pixels", 'cause the sentence is just cool!
scrumper•Apr 27, 2026
From the exploding pixels and then you're fine. You needed an H as well anyway.
grumpysysop•Apr 27, 2026
I wonder how small they can be. Would be an amazing watch display.
prima-facie•Apr 27, 2026
There's also the Atkinson dithering (made by Bill Atkinson) which produces very neat results.
dec0dedab0de•Apr 27, 2026
I love physical displays like this, or split flaps. Anything that is not a screen, and keeps it's display without power. I keep getting ads for vesta boards, but I just can't justify the expense.
I have notebook from ~15 years ago full of pie-in-the-sky ideas for different types of displays. This was before I got a job that took up all of my attention span.
danvillalon•Apr 27, 2026
I think a missed opportunity on the website would be to have a flip button to change the colors pallete too!
White background black text and flip back to the current one!
28 Comments
What was the cost/time breakdown of the entire project because the flipdisc prices are hidden behind quotes and it seems like it would take quite a lot of time to complete the whole display!
Similar to all the ePaper projects that show up here, they’re expensive but cool gimmicks.
The whole mechanism looks very 3d printable... I wonder if one could design one with PCB coils and a large 3d print only? If so, cost could probably come down to cents per pixel...
You'd probably also need a single 'C' shaped piece of steel for the magnetic flux path, but you might be able to find a supplier for the right shape already used for something else you can buy in large quantities very cheaply (eg. Steel staples).
I wonder if anyone makes cheaper versions that you're only supposed to update at 1 frame per minute or less...
EDIT: "They have high readability, a long lifespan, and achieves anywhere between 25-60fps" - I think you can't achieve 60fps with a flip dot display.
Remember that texas instruments DLP technology which is in use in pretty much every office/home cinema projector is effectively micro flip-dots micromachined in silicon, and that can operate at ~10,000 FPS.
EDIT: also when you google a bit you can find a guy who maxed out flip dot displays at 30fps (which honestly I thought would not be possible either)
But you can flip them fast/in parallel if you have a driver for each disc:
https://pierremuth.wordpress.com/2021/02/17/flipping-dots-fa...
I've been working on one and I have and I am trying to use an H-bridge per disc. It's possible to find very cheap ICs; for my 308 discs, it only cost $10 for these (not counting the additional time/costs that comes with coming up with 616 IO lines, getting a PCB made, dealing with power issues, etc):
https://www.lcsc.com/product-detail/C5795599.html
[2] https://www.urban-transport-magazine.com/wp-content/uploads/...
[1] https://cdn.unitycms.io/images/2padXosoqh99o13dcrN3co.jpg
Net Zero Fatigue is real.
You’re not doing your cause any favors by projecting everything on an ill-fitting frame.
In front of the flip dots is a frame that has a mini-LED that faces and front-lights each flip dot. This gives the appearance that each flip dot is glowing.
(1) https://m.youtube.com/watch?v=8Ru1DSs1tjQ
1. https://www.youtube.com/watch?v=FtutLA63Cp8
Niche indeed...
https://www.youtube.com/watch?v=eQ6rfI28zJ4
https://www.youtube.com/watch?v=BSdiop75jIg
https://www.youtube.com/watch?v=XQVp-srqRBY
https://www.youtube.com/watch?v=SJU2-1X8kHQ
https://www.youtube.com/watch?v=NiFSnoJQU7I
https://www.youtube.com/watch?v=UWIKOjGXTEM
I use quotes because it will always be the Colosseum to me, where I saw the Butthole Surfers, Dead Moon and Nirvana. Don’t get me started on the Kingdome.
https://github.com/simpsoka/office-flipdisc/blob/main/scenes...
Still, I wanna see and hear it on the display.
I occasionally connect wires to terminals, but - I've never used ferrules: I just self-twist the thin strands, push the thing in, and use the lever or tightening screw depending on the terminal's mechanism.
Why would I use a ferrule? Or perhaps, under what circumstances is that advised?
PS - Link to the ferrules they mentioned: https://www.amazon.com/gp/product/B07R6QQ7MW/
Ferrules also evenly distribute the clamping force and prevent crushing of the strands.
Ferrules solve the problem of having to align the threads every time you re-post them in a terminal block.
https://www.pippakelmenson.com/work/climate-pledge-arena
https://www.coleorloff.com/specifically/pitchbook
https://www.behance.net/gallery/136172923/Climate-Pledge-Are...
must be vrey annoying very fast if you have to sit next to it all day
Just one example: https://theartistbreakfast.com/works/traverse
Also created a larger more sculpted derivative the „brixel“ a rotating brick as pixel. Eg https://theartistbreakfast.com/works/oceans
Last I heard a number of years ago it’s around $2000/sq ft. Around the same price scale as mid range LED wall modules.
All I can see are bars of gold.
Here’s a clip of it moving (doesn’t read so well as a static image): https://theartistbreakfast.com/works/oceans
It would be interesting to see if you could run a pared-down version of that game on a display like this.
See on YouTube or visit in person
No, it's not ok to abandon those flipdisc displays! :(
Admittedly I read neither of the articles. But who doesn't sometimes get caught up in the conincidence of titles on here may vote me down :D
Nobody outside a gas station wants a glowy hole.
I have notebook from ~15 years ago full of pie-in-the-sky ideas for different types of displays. This was before I got a job that took up all of my attention span.
Very cool project!