A man’s hands are shown in the foreground holding two splines, each with teeth both on the interior and exterior surfaces. Both are identical in shape, but one is larger and made of plastic, and the other is smaller and made of metal.

Freeze-drying For Improved Metal Printing

June 6, 2025 by 12 Comments

For all the remarkable improvements we’ve seen in desktop 3D printers, metal printers have tended to stay out of reach for hackers, mostly because they usually rely on precise and expensive laser systems. This makes it all the more refreshing to see [Dan Gelbart]’s demonstration of Rapidia’s cast-to-sinter method, which goes from SLA prints to ceramic or metal models.

The process began by printing the model in resin, scaled up by 19% to account for shrinkage. [Dan] then used the resin print to make a mold out of silicone rubber, after first painting the model to keep chemicals from the resin from inhibiting the silicone’s polymerization. Once the silicone had set, he cut the original model out of the mold and prepared the mold for pouring. He made a slurry out of metal powder and a water-based binder and poured this into the mold, then froze the mold and its contents at -40 ℃. The resulting mixture of metal powder and ice forms a composite much stronger than pure ice, from which [Dan] was able to forcefully peel back the silicone mold without damaging the part. Next, the still-frozen part was freeze-dried for twenty hours, then finally treated in a vacuum sintering oven for twelve hours to make the final part. The video below the break shows the process. Continue reading “Freeze-drying For Improved Metal Printing” →

A woman in a richly-colored blue head scarf leans over a wooden table looking at the timer between her hands. The timer has a yellow circle on black flip panels on the left and black and white CT scans of a human torso on the right side. The frame is wood, and there is an electric motor on the upper right of the frame and a silver drum on the left of the frame beneath the woman's hand.

A Flip Clock Becomes A Flip Timer

June 6, 2025 by 2 Comments

Sometimes it’s nice to have a widget to do a single task and avoid getting distracted by the supposed simplicity of doing it with an app on a smartphone. [Dina Amin] built a timer from an old flip clock to stay focused.

Starting with a disassembly of the flip clocks she found at a flea market with [Simone Giertz], [Amin] decided to change the twenty four hour mechanism to a twenty four minute one which was similar to the amount of time she was already using for several different practices. Since she’s an expert in animation, she planned on turning a set of CT scans into the animation that would play on the section that had previously been the minutes of the clock.

As much of the original clock’s components were damaged, and [Amin] didn’t have a chance to learn clockmaking from scratch in a week, she tried a few different drive mechanisms for the build. The drum from an air fryer timer driven with an electric motor fit the bill, but off enough from proper minutes that [Amin] switched from numerals to a yellow circle that fills in as it approaches the satisfying ding of completion.

If you want to see Simone’s Moon flip clock we’ve covered that project too.

Continue reading “A Flip Clock Becomes A Flip Timer” →

A Network Status Panel The Way It Should Be

June 6, 2025 by 16 Comments

Sometimes a project forms itself around a component rather than an idea, and thus it was that [Maximilien] found himself building a data rate monitor for the connection between two data centers. Some MD0657C2-R LED dot matrix displays for not a lot needed a project.

The displays are mounted in groups of four on small PCBs, driven by a MAX6952, which are then controlled by a Pi Pico. There are several display panels in the project, each of which is a pained and laser-etched acrylic sheet with a pair of the LED boards mounted behind it. These in turn go on the front of a wooden enclosure, with a set of LED ring lights behind to illuminate the etched parts of the panels. Each display panel has its own Pico, daisy chained together and driven by a Pico W that supplies network connectivity.

As you might expect, this isn’t the first status panel we’ve brought you over the years.

Hackaday Podcast Episode 324: Ribbon Microphone From A Gumstick, Texture From A Virtual Log, And A Robot Arm From PVC

June 6, 2025 by 5 Comments

This week, Hackaday’s Elliot Williams and Kristina Panos joined forces to bring you the latest news, mystery sound, and of course, a big bunch of hacks from the previous week.

In Hackaday news, the 2025 Pet Hacks Contest rolls on, but only for a short time longer. You have until Tuesday, June 10th to show us what you’ve got, so head over to Hackaday.IO and get started now! In other news, check out what adaptive optics can do when it comes to capturing pictures of the Sun. In other, other news, there won’t be a Podcast next week as Elliot is on vacation.

On What’s That Sound, Kristina failed once again, but four of you guessed correctly. Congratulations to [ToyoKogyo12aTurbo] who fared better and wins a limited edition Hackaday Podcast t-shirt!

After that, it’s on to the hacks and such, beginning with a largely-printed 6-DOF robot arm. We take a look at a bunch of awesome 3D prints like guitars and skateboards, take a look at some pet hacks, and discuss brick layers in orcaslicer. Finally, we talk a lot about keyboards, especially the quickly-evaporating Blackberry keyboards and why they’re disappearing.

Check out the links below if you want to follow along, and as always, tell us what you think about this episode in the comments!

Download in DRM-free MP3 and savor at your leisure.

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Continue reading “Hackaday Podcast Episode 324: Ribbon Microphone From A Gumstick, Texture From A Virtual Log, And A Robot Arm From PVC” →

Laser soldering

Solder Stencil Done Three Ways

June 6, 2025 by 29 Comments

This project, sent in by [Henk], goes through a few different ways to make a solder stencil using a vinyl cutter, a CO2 laser, and a fiber laser.

The project starts with identifying a method to convert the board’s Gerber files to a PNG, which is ultimately used to create a vector file for use with the laser. The first stencil, made with the CO2 laser, was cut out of masking tape. This worked fine for larger cutouts and is certainly a cheap option if you don’t have too many small components. A slightly better approach with the CO2 laser was using vinyl sheet release paper, which seemed to hold together better than the tape.

Laser-cut masking tape works, but not for long.

A vinyl cutter was also used as an experiment, but it didn’t perform as well as the CO2 laser, as expected, since the cutter uses a knife rather than light, leading to some tearing issues.

The final method utilized a fiber laser and an empty drink can to create a metal stencil. First, the can had to be cut open, heated, and flattened. The fiber laser was able to cut clean footprints in the aluminum, creating a stencil that would hold up to more use than the paper variations.

The finale of this exploration into laser stencil making was using the fiber laser to solder the board together. The stencil was used to spread paste on the pads, parts were placed on the board, and then the fiber laser heated the solder paste to solder them to the board. The board looked a bit toasty afterwards, but we imagine the process could be fine-tuned to reduce the collateral damage a bit.

Once you’ve got your stencil ready to go, you can combine it with a 3D printed jig to hold the PCB while you apply the solder paste.

This Week In Security: Roundcube, Unified Threat Naming, And AI Chat Logs

June 6, 2025 by 4 Comments

Up first, if you’re running a Roundcube install prior to 1.5.10 or 1.6.11, it’s time to update. We have an authenticated Remote Code Execution (RCE) in the Roundcube Webmail client. And while that’s not quite the level of chaos that an unauthenticated RCE would cause, it’s still to be taken seriously. Mainly because for the majority of the 53 million Roundcube installs out there, the users aren’t entirely trusted.

The magic at play in this vulnerability is the Roundcube user session code, and specifically the session deserialization scheme. There’s a weird code snippet in the unserialize function:
if ($str[$p] == '!') {
$p++;
$has_value = false;

The exclamation mark makes the code skip a character, and then assume that what comes next has no value. But if it does actually have a value, well then you’ve got a slightly corrupted deserialization, resulting in a slightly corrupted session. This really comes into force when combined with the file upload function, as the uploaded filename serves as a payload delivery mechanism. Use the errant exclamation mark handling to throw off deserialization, and the filename can contain arbitrary session key/value pairs. A GPG class from the PEAR library allows running an arbitrary command, and this can be hijacked with the session manipulation. Continue reading “This Week In Security: Roundcube, Unified Threat Naming, And AI Chat Logs” →

In Film, What’s Old May Still Be New Again

June 6, 2025 by 15 Comments

We recently published an affectionate look at a Polaroid Land camera, whose peel-apart instant film is long out of production except for a very few single exposure packs form a boutique manufacturer. All that was left was a discussion of modifying it for conventional roll film, or perhaps hacking a modern back-to-front Polaroid sheet into it.

Never say never though, because along come the Chinese company Light Lens Lab with a short announcement at the end of a post talking about grain structures and anti-halation layer materials for their black and white film.

Lastly, with our future development plan, we are currently developing and researching instant peel-apart film, with plans on producing and making available black and white peel-apart film by 2025 in various format. We aim to have an update on our packaging and test shot for the next development/research progress installment. We are also researching, developing and producing colour reversal films that consist of a dye-incorporating development process, commonly known as K-14, for 135 and 120 formats in 2026.

So there you go, no sooner has Hackaday declared a format unavailable, than it shows every sign of reappearing. At this point we’d like to take the opportunity to report that McDonalds Szechuan Chicken McNugget sauce will never ever be available again. Continue reading “In Film, What’s Old May Still Be New Again” →