Hackaday Podcast Ep 385: 3D Printers With Lasers, Wicked RAM Prices, And Reverse Polish Notation

September 4, 2026 by No comments

As the calendar turns a leaf into September, Elliot Williams is joined by Jenny List for our weekly look at all things Hackaday.

In the news, our retrocomputing competition is well under way, but there’s plenty of time to get an entry in if you’ve got a cool old-style project to show us. And then Elliot’s been chasing seismic surveyors in Munich, where they’re looking for geothermal energy.

In the stand-out hacks there’s a discussion of smoothing 3D prints using frickin’ lasers, the effect of unreasonably high RAM and storage prices on the single board computer ecosystem, and an unfortunate air conditioning system that’s tricked into believing it’s a hot day. Finally, we look in depth at PETG, and take a dive into reverse Polish notation.

Download your own personal version of the podcast right here.

Where to Follow Hackaday Podcast

Places to follow Hackaday podcasts:

Continue reading “Hackaday Podcast Ep 385: 3D Printers With Lasers, Wicked RAM Prices, And Reverse Polish Notation” →

3D Printed Cubes Provide Passive Cooling

September 4, 2026 by 4 Comments

Passive evaporative cooling has been used for centuries to reduce temperatures. Heat is drawn off as water evaporates, which in turn reduces temperature. The more efficiently this process happens the greater the temperature differential, and that’s exactly what the 3D-printed structure pictured above aims for. Created at the Graz University of Technology in Austria, the cubes noticeably reduce surrounding air temperature thanks to their careful construction. As long as they’re kept wet, anyway.

The key is exposing the maximum amount of water to the maximum amount of airflow, and there are two ways the prototype cooling wall — which is 3D printed from a special clay mixture — does this.

First, the macro design of the 3D-printed blocks maximizes surface area. If the cube in the image above looks familiar, that’s because it’s the gyroid infill pattern. Gyroid is a porous pattern with no “dead ends” or closed sections, and the fact that it 3D prints cleanly with no supports also makes it an ideal structural candidate.

The second advantage is the clay used for the blocks themselves. Firing clay at a low temperature keeps it porous, but this particular mixture goes even further. It’s a bio-inspired formulation of clay, fungal mycelium, and wood chips. After printing, the cubes are fired and the fungus and wood chips burn away, leaving a network of thread-like capillaries with occasional larger pockets throughout.

The result is a porous ceramic cube with a massive evaporative surface area relative to its size. A practical test in a hot attic showed the air near a water-laden cube was nearly 7º C lower, a noticeable difference.

A home experimenter might not have access to fancy mycelium-laced clay mixtures, but it still strikes us as something that could be tried out at home. After all, clever hackers have successfully made DIY versions of passive cooling paint.

This Week In Security: Baked-in Malware, Freezers Not Freezing, Zoom Snoops Clipboards, And AI Makes Things Worse, Faster

September 4, 2026 by 4 Comments

The AI platform ServiceNow which offers both hosted and on-premises versions just patched a trifecta of CVSS-10 vulnerabilities.

CVSS rankings are determined by the severity of a flaw, the ease of exploiting the bug, if authentication is required for exploitation, if the vulnerability exposes confidential data, and other criteria. A CVSS of 10 is as bad as it gets, and having three of them at once is certainly attention-getting. Of the three vulnerabilities fixed, one allowed unauthenticated modification of data in the hosted instance, a second allowed arbitrary code execution via the GraphQL interface, and the third allowed arbitrary SQL commands that could modify the database.

ServiceNow claims Adobe, Lenovo, Fedex, and Fujitsu among their high-profile customers. With luck, the vulnerabilities were patched before significant public exploitation could happen.

Router Malware

Previously in 2026 the US Government warned against embedded malware found in consumer routers, which may be linked to the FCC enacting bans against certification and import of foreign-made consumer devices. This week, the NVD (National Vulnerability Database) reported specific embedded malware in the Zbtlink and MoreQuick brands of devices.

Multiple versions of the firmware, for multiple lines of products, contain a backdoor service that uses unencrypted UDP to connect to a command and control (C2) service. The service, or anyone able to intercept the network traffic, since it’s unencrypted, can execute commands as root, allowing them to change configurations, open tunnels, or steal ISP credentials.

The malware is baked into the firmware, so removing it is impossible for most users: a factory reset wouldn’t do. In theory if third-party firmware like OpenWRT supports these devices, the hardware could be made safer with a custom install.

Given how commonly the same device is marketed under dozens of names, likely the same devices and firmware have yet to be identified under other brands. Continue reading “This Week In Security: Baked-in Malware, Freezers Not Freezing, Zoom Snoops Clipboards, And AI Makes Things Worse, Faster” →

Take Tool Photo, Generate Custom Gridfinity Bin

September 4, 2026 by 14 Comments

What if the organization and storage benefits of tool shadowing could be had and improved with a modular, semi-automated process? Tracefinity attempts that by generating custom Gridfinity bins from photos of tools, and has quite a few nifty features that are worth a look.

Maintaining a library of tools makes it easy to create project-based custom layouts.

The basic workflow is this: place one or more tools on a sheet of paper, take a photo, then upload the photo and have the system trace and save the outline and add it to a private tool library. When one is ready to create some bins, use the library of saved tool outlines to generate custom Gridfinity layouts.

If you’re unfamiliar, Gridfinity is a modular system of standardized bins and baseplates designed with 3D printing in mind, making it an ideal match for highly-customized organization tasks and a particularly natural fit for a tool-tracing system like this one.

The idea of taking a photo of a tool and generating a custom bin is a compelling one, and a couple years ago we covered a project that did just that. Tracefinity seems like a natural evolution of the idea, and includes handy features like easy design adjustments, optional magnet holes, and we really like the concept of a tool library from which individual tools are scanned once then later selected to create specific, project-based layouts.

Tracefinity takes advantage of new software capabilities like machine learning to improve and streamline the tracing process, but that doesn’t mean it relies on any external services. It can be entirely self-hosted and by default uses a local, CPU-friendly object detection model for tool tracing. There is an option to provide a API key to use Google Gemini instead, but it’s not required. It can come in handy for especially complex tool outlines or dealing with non-ideal source photos, however.

The Birds Outside, Drawn For You Automatically

September 4, 2026 by 18 Comments

With artificial intelligence being the bête noir of the moment, there are some projects using it which maybe don’t bring much to the table. So it’s nice to see one that uses it in a creative way, and delivers something new. [arnegiacomo]’s e-paper screen is a great example, as it draws a picture in real time of whatever birds are outside.

Behind the quite large screen sits a Raspberry Pi 5, and on that is BirdNet-Go, an AI-powered birdsong classifier. A USB microphone catches the birdsong, and Birdnet comes up with the species. The birds on the display are then those species as pictures from 19th century bird spotters guides, assembled into a collage. You can even see what the current set of birds it hears are, live, and they are a representative cross section of the European birds you’d find in Norway where it’s located.

We like this project, both for the bird book vibe it gives, and the creative use of machine classification. Surprisingly this isn’t the first project in this field we have seen over the years.

A small rocket is shown launching into the sky, with a trail of smoke leading into the mount of a black pipe. Four large plastic pieces are falling away from below the rocket.

Tube Launch Boosts Rocket’s Performance

September 3, 2026 by 11 Comments

If you want improve a model rocket’s performance, all the common options come with serious trade-offs: you could increase the motor’s size, which raises safety issues, or you could cut down on weight, which limits the possible payload. [Con Hathy] was therefore intrigued by the design of the Arcas sounding rockets, which with the aid of a gas-fed launch tube could reach an altitude of 100 km. Even in models without a gas generator, a launch tube apparently boosted performance, an effect which [Con] was able to replicate in a much smaller model rocket.

In theory, as the rocket engine fires, it should pressurize the tube behind the rocket, providing an extra boost out of the tube. To test this, [Con] 3D printed a test rocket, launched it both from a standard rail and from a tube, and compared the results. During tube launches, a printed sabot fit around the rocket and formed a seal with the launch tube. The results were surprising: the tube-launched rocket actually performed substantially worse than a rail launch. After building a simulation, [Con] found that, as the rocket moves down the tube, the volume of tube it needs to back-fill with gas increases faster than the engine puts out exhaust; it was pulling a slight vacuum behind it, slowing itself down.

To solve this, [Con] decreased the diameter of the launch tube. To let the rocket fit into the tube, he also modified it to use pop-out stabilizer fins which wrap around the rocket while in the tube. The sabot was also shrunk, and had foam added to improve the seal between it and the rocket. For this second test, [Con] also connected a pressure sensor to the base of the launch tube. The results on the second launch were much better: according to an altimeter, it managed to fly 72% higher. Based on the pressure sensor’s data, a longer tube could have squeezed out still more performance, but this still demonstrated the principle quite well.

We’ve seen a tube-launched rocket before, though not with such a performance focus.

Continue reading “Tube Launch Boosts Rocket’s Performance” →

Corners Lifting On 3D Prints? Guide Gives Prevention Tips

September 3, 2026 by 14 Comments

Large prints have a risk of warping, by which we mean corners can lift off the print bed as the object sort of curls inward on itself. It’s not always due to poor filament quality or an unclean build plate. Sound like something you’ve dealt with? Check out this handy roundup to understand why it happens, and learn ways to prevent it.

A big flat area with sharp corners is susceptible to warping. Breaking the footprint into a grid pattern helps distribute stresses instead of concentrating them at the corners.

The reason some objects have trouble while others don’t is physics. Deposited plastic shrinks ever so slightly as it cools, and some shapes — like wide, flat surfaces with sharp corners — are worse for this than others. This sort of problem is what the guide addresses with a number of techniques.

Some are simple, like turning on brims which increases an object’s footprint. This increased surface area offers more adhesion, but also increases heat transfer from the print bed into the model, slowing the cooling process. Thinner walls and an altered infill pattern is another option. Other techniques are more complex.

The most effective methods involve modifying the model itself to reduce or eliminate stress points. One such method is to break the model’s footprint into multiple zones with a shallow grid. Instead of one big flat bottom, the object has multiple smaller ones. Because big flat areas are more susceptible to warping than small ones, turning the bottom into a grid pattern helps spread those stresses out and prevent lifting.

If you design your own models, you’ll find several design tips worth keeping in mind. It’s always smart to practice good DFM (Design For Manufacturability) which means taking 3D printer strengths and weaknesses into account when designing an object. In this case, it can help prevent print failures. Good DFM can also make parts much, much stronger just by designing in the right features.