How To Use Tiny Open Loop Actuators For A Living Mirror

January 19, 2026 by Maya Posch 5 Comments

How do you go about making a mirror with 128 segments, each of which can be independently angled? That was the question that a certain bloke over at [Time Sink Studio] found himself pondering on, to ultimately settle on a whole batch of mini-actuators bought through AliExpress. These stepper-based actuators appear to be akin to those used with certain Oppo smartphones with pop-up camera, costing less than half a dollar for a very compact and quite fast actuator.

The basic design is very much akin to a macro version of a micromirror device, as used in e.g. DLP projectors, which rely on a kinetic mirror mount to enable precise alignment. With the small actuators travelling up to 8 mm each, the mirrors can cover 73 mm at a distance of 4 meters from a wall.

With the required angle of the mirror being effectively just the application of the Pythagorean theorem, the biggest challenge was probably calibrating these linear motors. Since they’re open loop devices, they are zeroed much like the steppers on 3D printers, by finding the end limit and counting steps from that known point. This doesn’t make drift impossible, but for projecting light onto walls it’s clearly more than good enough.

Continue reading “How To Use Tiny Open Loop Actuators For A Living Mirror” →

SoundSlab: How To Make A Synthesizer With All The Button Screens

January 19, 2026 by Maya Posch 11 Comments

Although arguably redundant on a typical computer keyboard, the idea of embedding small screens into the buttons on devices like audio production gear that often have so many buttons can make a lot of sense. As exemplified by devices with a UX that regularly degrades into scrolling through options on a tiny screen. This was basically the impetus for [Craig J Bishop] a few years ago to set out on a design project called the SoundSlab audio sequencer/sampler/synthesizer and slab that would make those buttons much more functional.

Obviously, the right way to start the project is to bulk buy hundreds of 0.85″ 128×128 LCDs so that you’re firmly locked into that choice. Fortunately, it turned out that the most annoying part of this LCD was the non-standard 0.7 mm pitch on its flat flex cable (FFC). This was worked around with an PCB adapter milled out of some copper-clad FR-1, which gave it a convenient PMOD interface for straightforward hook-up to a Xilinx Artix-7 FPGA board.

The buttons themselves were designed as 3D printed key caps for the LCDs that clipped onto typical Cherry MX-style mechanical keys. This also revealed that the original FFCs were too short, so they had to be replaced with new FFCs, that also adapted it to a standard 0.5 mm pitch. With this a 4×4 button prototype board could be constructed for testing.

Since that prototype [Craig] has built a full-sized SoundSlab grid, with a custom FPGA board and HDMI input, of which a preview can be seen in the post, along with a promise by [Craig] to soon post the rest of the SoundSlab development.

Thanks to [JohnS_AZ] for the tip.

Washington State Bill Seeks To Add Firearms Detection To 3D Printers

January 19, 2026 by Maya Posch 181 Comments

Washington State’s House Bill 2321 is currently causing a bit of an uproar, as it seeks to add blocking technologies to 3D printers, in order to prevent them from printing “a firearm or illegal firearm parts”, as per the full text. Sponsored by a sizeable number of House members, it’s currently in committee, so the likelihood of it being put to a floor vote in the House is still remote, never mind it passing the Senate. Regardless, it is another chapter in the story of homemade firearms, which increasingly focuses on private 3D printers.

Also called ‘ghost guns‘ in the US, these can be assembled from spare parts, from kits, from home-made components, or a combination of these. While the most important parts of a firearm, like the barrel, have to be made out of something like metal, the rest can feature significant amounts of plastic parts, though the exact amount varies wildly among current 3D-printed weapons.

Since legally the receiver and frame are considered to be ‘firearms’, these are the focus of this proposed bill, which covers both additive and subtractive technology. The proposal is that a special firearms detection algorithm has to give the okay for the design files to be passed on to the machine.

Continue reading “Washington State Bill Seeks To Add Firearms Detection To 3D Printers” →

What To Do With A Flash-less ESP32-C3 Super Mini Board?

January 18, 2026 by Maya Posch 33 Comments

In an update video by [Hacker University] to an earlier video on ESP32-C3 Super Mini development boards that feature a Flash-less version of this MCU, the question of adding your own Flash IC to these boards is addressed. The short version is that while it is possible, it’s definitely not going to be easy, as pins including SPIHD (19) and SPICLK (22) and SPIQ (24) are not broken out on the board and thus require one to directly solder wires to the QFN pads.

Considering how sketchy it would be to have multiple wires running off to an external Flash IC, this raises many questions about the feasibility, as well as cost-effectiveness. Some in the comments to the video remark that instead you may as well swap the MCU with a version that does contain built-in Flash, but this is countered with the argument that a new ESP32-C3 Super Mini board with the right MCU costs as much as a loose MCU from your favorite purveyor of ICs.

Ultimately this lends some credence to calling these zero Flash Super Mini boards a ‘scam’, as their use cases would seem to be extremely limited and their Flash-less nature very poorly advertised.

Continue reading “What To Do With A Flash-less ESP32-C3 Super Mini Board?” →

Beating The World Record For Fastest Flying Drone Once Again

January 18, 2026 by Maya Posch 21 Comments

The fun part about world records is that anyone can take a swing at breaking them, which is what [Luke Maximo Bell] has been doing with the drone speed record for the past years, along with other teams in a friendly competition. After having some Aussie blokes previously smash the record with a blistering 626 km/h, the challenge was on for [Luke] and his dad to reclaim the title. This they did with the V4 of their quadcopter design, adding a range of improvements including new engines, new props and an optimized body to eek out more performance.

In the video we see these changes and the tests in detail. Interestingly, the simulations ran on the computer showed that the new body actually had to be larger, necessitating the use of a larger FDM printer. Fortunately a certain FDM 3D printer company sponsors just about everyone out there, hence the new design was printed on a Bambu Lab H2D, also making use of the dual extruder feature to print combined PETG/TPU parts.

It was also attempted to have a follow camera attached to a second FPV done in the form of a 360 degrees camera, but this turned out to be a bit too complex to get good shots, so this will have to be retried again.

In the end a new world record was set at an average of 657 km/h, which sets the stage for the next team to try and overtake it again. As for where the limit is, propeller airplanes have hit over 800 km/h, so there’s still quite a way to go before details like the sound barrier become a problem.

Continue reading “Beating The World Record For Fastest Flying Drone Once Again” →

The Shelly 2.5 Smart Relay Design Flaw Killing Capacitors

January 17, 2026 by Maya Posch 32 Comments

Part of any self-respecting Smart Home, smart relays are useful for switching and monitoring loads that do not plug into an outlet. This also makes them a lot more integrated, and thus, a long lifespan is very welcome. Unfortunately, the popular Shelly 2.5 smart relays seem to be having a bit of a design flaw as they’re dying in droves once their 2-year warranty period is up. The cause and repair are covered in a recent [VoltLog] video on YouTube.

As noted in the Shelly documentation for the device, it’s a very compact form factor device, with screw terminals, two relays, and three fairly large electrolytic capacitors sharing very little space with the rest of the components. The apparent flaw comes in the form of these capacitors failing, with the video showing that one 100 µF capacitor has a massively increased ESR, likely due to electrolyte venting. This results in the observed symptoms, such as WiFi connectivity issues and audible hissing, the latter of which is demonstrated in the video.

Continue reading “The Shelly 2.5 Smart Relay Design Flaw Killing Capacitors” →

The Journey Of Finding The Right Press Brake

January 17, 2026 by Maya Posch 10 Comments

Press brakes are invaluable tools when working with sheet metal, but along with their almost infinite versatility comes a dizzying number of press brake types. After starting with an old-school, purely mechanical press brake, [Wes] of Watch Wes Work fame had been thinking of upgrading said press brake to a hydraulic configuration, but soured on this after facing all the disadvantages of the chosen approach. Thus, one does what any rational person does and purchases a used and very much untested 45-ton computer-controlled hydraulic press brake.

The video first explores the pros and cons of the various types of press brakes, with the issue of providing a balanced force across the entirety of the press brake’s dies being the largest problem. Although various mechanical and hydraulic solutions were attempted over the decades, a computer-controlled press brake like this Gasparini PBS 045 that [Wes] got is probably one of the more effective solutions, even if it provides the headache of more electrical and electronic things that can go wrong. The above screenshot of its basic workings should make that quite obvious, along with [Wes]’s detailed explanation.

As it turned out, this about 25-year-old Italian press brake wasn’t in such a terrible nick, but needed some badly needed TLC and obligatory breaker testing to bring it back to life. While it doesn’t like you not centering the part, this can be worked around by specifying that the part is actually larger than it is. Although [Wes] got it working well enough to do some work with it, it still has some gremlins left in it that will hopefully be hunted down over the coming time and video(s).

Continue reading “The Journey Of Finding The Right Press Brake” →