Jointly Is A Typeface Designed For CNC Joinery

September 16, 2025 by Tyler August 23 Comments

If you have a CNC router, you know you can engrave just about any text with the right tool, but Jointly is a typeface that isn’t meant to be engraved. That would be too easy for [CobyUnger]. His typeface “Jointly” is the first we’ve seen that’s meant to be used as joinery.

The idea is simple: carve mortises that take the shape of letters in one piece, and carve matching letter-tenons into the end of another. Push them together, and voila: a joint! To get this concept to work reliably, the font did have to be specially designed — both the inner and outer contours need to be accessible to a rotary cutting tool. Cutting tools get harder to use the smaller they go (or more fragile, at any rate) so with Jointly, the design spec was that any letters over 3/4″ (19.05 mm) tall needed to be handled with a 1/8″ (3.175 mm) rotary cutter.

This gives the font a friendly curved appearance we find quite fetching. Of course if you’re going to be cutting tenons into the end of a board, you’re going to need either some serious z-depth or an interesting jig to get the end of the board under the cutting head. It looks like [CobyUnger] has both, but he mentions the possibility of using a handheld CNC router as the cheaper option.

Speaking of routing out type, do you know the story of Gorton? You can’t make joinery with that typeface, but you’ve almost certainly seen it.

A lathe is shown on a tabletop. Instead of a normal lathe workspace, there is an XY positioning platform in front of the chuck, with two toolposts mounted on the platform. Stepper motors are mounted on the platform to drive it. The lathe has no tailpiece.

Turning A Milling Machine Into A Lathe

September 13, 2025 by Aaron Beckendorf 8 Comments

If you’re planning to make a metalworking lathe out of a CNC milling machine, you probably don’t expect getting a position sensor to work to be your biggest challenge. Nevertheless, this was [Anthony Zhang]’s experience. Admittedly, the milling machine’s manufacturer sells a conversion kit, which greatly simplifies the more obviously difficult steps, but getting it to cut threads automatically took a few hacks.

The conversion started with a secondhand Taig MicroMill 2019DSL CNC mill, which was well-priced enough to be purchased specifically for conversion into a lathe. Taig’s conversion kit includes the spindle, tool posts, mounting hardware, and other necessary parts, and the modifications were simple enough to take only a few hours of disassembly and reassembly. The final lathe reuses the motors and control electronics from the CNC, and the milling motor drives the spindle through a set of pulleys. The Y-axis assembly isn’t used, but the X- and Z-axes hold the tool post in front of the spindle.

The biggest difficulty was in getting the spindle indexing sensor working, which was essential for cutting accurate threads. [Anthony] started with Taig’s sensor, but there was no guarantee that it would work with the mill’s motor controller, since it was designed for a lathe controller. Rather than plug it in and hope it worked, he ended up disassembling both the sensor and the controller to reverse-engineer the wiring.

He found that it was an inductive sensor which detected a steel insert in the spindle’s pulley, and that a slight modification to the controller would let the two work together. In the end, however, he decided against using it, since it would have taken up the controller’s entire I/O port. Instead, [Anthony] wired his own I/O connector, which interfaces with a commercial inductive sensor and the end-limit switches. A side benefit was that the new indexing sensor’s mounting didn’t block moving the pulley’s drive belt, as the original had.

The end result was a small, versatile CNC lathe with enough accuracy to cut useful threads with some care. If you aren’t lucky enough to get a Taig to convert, there are quite a few people who’ve built their own CNC lathes, ranging from relatively simple to the extremely advanced.

Camera And ChArUco Keep The Skew Out Of Your 3D Prints

September 6, 2025 by Dan Maloney 20 Comments

Do you or a loved one suffer from distorted 3D prints? Does your laser cutter produce parallelograms instead of rectangles? If so, you might be suffering from CNC skew miscalibration, and you could be entitled to significant compensation for your pain and suffering. Or, in the reality-based world, you could simply fix the problem yourself with this machine-vision skew correction system and get back to work.

If you want to put [Marius Wachtler]’s solution to work for you, it’s probably best to review his earlier work on pressure-advance correction. The tool-mounted endoscopic camera he used in that project is key to this one, but rather than monitoring a test print for optimum pressure settings, he’s using it to detect minor differences in the X-Y feed rates, which can turn what’s supposed to be a 90-degree angle into something else.

The key to detecting these problems is the so-called ChArUco board, which is a hybrid of a standard chess board pattern with ArUco markers added to the white squares. ArUco markers are a little like 2D barcodes in that they encode an identifier in an array of black and white pixels. [Marius] provides a PDF of a ChArUco that can be printed and pasted to a board, along with a skew correction program that analyzes the ChArUco pattern and produces Klipper commands to adjust for any skew detected in the X-Y plane. The video below goes over the basics.

For as clever and useful as ChArUco patterns seem to be, we’re surprised we haven’t seen them used for more than this CNC toolpath visualization project (although we do see the occasional appearance of ArUco). We wonder what other applications there might be for these boards. OpenCV supports it, so let us know what you come up with.

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Spinning Top Chair Revisited

September 6, 2025 by Fenix Guthrie 11 Comments

Designer furniture generally comes with excellent aesthetics and (sometimes) functionality. However, such furniture comes with a price to match. One such piece of furniture is the Magis Spun Chair. It’s a striking piece with a fun party trick to match: it works like a top spinning while you sit inside. However, it has a prohibitively expensive price tag of $1,200 to match. That’s why [Morley Kert] is on a mission to build one for less.

This isn’t [Morley]’s first time building a spinning chair. The first attempt featured numerous 3D printed pieces glued together. It did not inspire confidence in spinning, nor was it a striking piece of furniture. So a revisit was in order.

This time around the chair’s construction was CNC milled plywood. Some surfaces featured 3D carving, but the majority were left raw with carving the final shape handled manually. Despite its size, the chair only took four and a half sheets of 3/4 inch plywood by hollowing out the base allowing for more efficient use of material. Once the router had completed the pieces, they were stacked and glued together. Each layer was aligned with hidden dowels making the assembly process fairly straightforward.

However, while usable, the chair looked rather unfinished, so [Morley] went to town on it with a power carving angle grinder. To ensure even carving on the circular profile of the chair, he placed it, or for some sections glued it, on an electronic lazy Susan. After some practice, the carving process turned out really well with a well-shaped and professional looking chair. Some wood varnish and a large amount of sanding finished up the chair very nicely for a total material cost of under $500.

We were happy to see the completion of this chair building saga. If you want to see [Morley] make even more designer furniture for cheap, make sure to check out his other 3D printed chair!

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Don’t Say This DIY Diskette Was A Flop

August 11, 2025 by Tyler August 21 Comments

Sometimes, you build a thing because you need a thing. Sometimes, you do it just to see if you can. This project is in category two: [polymatt] didn’t need to create a floppy disk from scratch-– plenty of old disks still exist– but we’re glad he made the attempt because it makes for a fascinating video that’s embedded below.

Some of you are going to quibble with the terminology [polymatt] uses in this video: first of all, he didn’t begin by creating the universe, so is he really starting “from scratch”? Secondly, the “floppy” format he’s attempting to copy is a 3½” diskette, which does not flop at all.

Choosing newer stiff-walled medium does allow him to practice his CNC skills and make the coolest-looking floppy enclosure we’ve ever seen. (It turns out brushed aluminum is even cooler-looking than the translucent neon ones.) On the other hand, we can’t help but wonder if a lower-density format 5¼” disk might have been an easier hurdle to jump. The diskette that was built does magnetize, but it can’t read or write actual files. We wonder if the older format might have been more forgiving of grain size and composition of his ferrite coating. Even more forgiving still would be to use these techniques to make magnetic tape which is a perfectly viable way to store data.

Instead of storing data, you could make your own cleaning floppy. It’s not like data storage was really the point here, anyway– its not the destination, but the journey. So whatever you call this DIY diskette, please don’t call it a flop.

Thanks to [Anonymous] for the great tip!

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The Kilopixel Display

August 9, 2025 by Jenny List 7 Comments

Despite the availability of ready-made displays never being better, there are still some hardy experimenters who take on the challenge of making their own. In [Ben Holmen]’s case the display he built is somewhat unusual and not the most practical, but for us a giant-sized wooden kilopixel display is exactly what the world needs.

It’s a kilopixel display because it has a resolution of 40 by 25 pixels, and it takes the form of a rack of wooden cubes, each of which can be turned by a tool on a gantry to expose either a black or a white side. It’s very slow indeed — he has an over nine hour long video of it in operation — but it is an effective device.

His write-up goes into great detail about the steps taken in its design, starting with spherical pixels rotated by a LEGO wheel and progressing to cubes poked at their corner to rotate. The pusher in this case is a hot glue stick, for the required flexibility. For practicality we’re reminded of this serial oil-and-water display.

The whole thing is online, and if you want you can submit your own images for it to draw. Whether a Wrencher in 25 pixel resolution has enough detail, we’ll leave to you.

Clock Of Clocks Expands, Goes Digital

August 8, 2025 by Tyler August 9 Comments

Some people just want to have their cake and eat it too, but very few of us ever get to pull it off. [Erich Styger] has, though with V5 of his “MetaMetaClock”— a clock made of clocks, that uses the orientation of the hands to create digits.

We’ve seen previous versions of this clock. As before, the build is exquisitely detailed and all relevant files are on GitHub. This version keeps the acrylic light-pipe hands of version 4, but adds more of them: 60 clocks vs 24. Larger PCBs are used, grouping the dual-shaft steppers into groups of four, instead of the individual PCBs used before. Each PCB has an NXP LPC845 (a Cortex M0 microcontroller) that communicates on an RS-485 bus. Placing four steppers per microcontroller reduces parts count somewhat compared to previous versions (which had each ‘clock’ on its own modular PCB) albeit at the cost of some flexibility.

While the last version used veneers on its face, this version is cut by CNC by from a large slab of oak. It’s certainly the most attractive version yet, and while bigger isn’t always better, more clock faces means more potential effects. Date? Time? Block letters? Arbitrary text? Kaleidoscopic colours from the RGB LEDs? It’s all there, and since it’s open source, anyone who builds one can add more options. A BLE interface makes it quick and easy to wirelessly switch between them or set the time.

It’s nice sometimes to watch projects like this improve incrementally over time. [Erich] mentions that he plans to add Wifi and a web-based user interface for the next version. We look forward to it, and are grateful to [jicasi] for the tip. Just as it is always clock time at Hackaday, so you can always toss a tip of your own into the box.

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