Removing Infill To Make 3D Printed Parts Much Stronger

October 12, 2025 by Maya Posch 22 Comments

When it comes to FDM 3D prints and making them stronger, most of the focus is on the outer walls and factors like their layer adhesion. However, paying some attention to the often-ignored insides of a model can make a lot of difference in its mechanical properties. Inspired by a string of [Tom Stanton] videos, [3DJake] had a poke at making TPU more resilient against breaking when stretched and PLA resistant to snapping when experiencing a lateral force.

Simply twisting the TPU part massively increased the load at which it snapped. Similarly, by removing the infill from the PLA part before replacing it with a hollow cylinder, the test part also became significantly more resilient. A very noticeable result of hollowing out the PLA part: the way that it breaks. A part with infill will basically shatter. But the hollowed-out version remained more intact, rather than ripping apart at the seams. The reason? The hollow cylinder shape is printed to add more walls inside the part. Plus cylinders are naturally more able to distribute loads.

All of this touches on load distribution and designing a component to cope with expected loads in the best way possible. It’s also the reason why finite element analysis is such a big part of the CAD world, and something which we may see more of in the world of consumer 3D printing as well in the future.

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Bose SoundTouch Smart WiFi Speakers Are About To Go Dumb

October 11, 2025 by Maya Posch 32 Comments

Bose SoundTouch speakers were introduced in 2013, offering the ability to connect to online streaming services and play back audio on multiple speakers simultaneously using the accompanying mobile app. Now these features are about to be removed, including the mobile app, as Bose is set to discontinue support on February 18, 2026. From that point onwards, you can only use them via Bluetooth or physical connectors that may be present, like an audio jack or HDMI port. This includes fancy home theater system hardware like the above SoundTouch 520.

That is the official line, at least. We have seen the SoundTouch on Hackaday previously, when it was discovered how to gain root shell access to the Linux OS that powers the original SoundTouch system with Telnet access on port 17,000 to pass the listening service the remote_services on command before connecting with Telnet as usual, with root and no password. A quick glance at the comments to that post suggests that this is still a valid approach for at least certain SoundTouch devices.

The fallout from this announcement appears to be twofold: most of all that ‘smart’ features like WiFi-based streaming can be dropped at any time. But it also makes us realize that hardware hackers like us will never run out of new and suddenly obsolete hardware that need our rescue.

Entering The Wild World Of Power Over Ethernet

October 11, 2025 by Maya Posch 50 Comments

As Ethernet became the world-wide standard for wired networking, there was one nagging problem. You already have to plug in the network cable. But then you have to also plug in a power cable. That power cable needs to be long enough. And have the right plug on it for your country. And provide the right current and voltage. That’s how Power over Ethernet (PoE) was born, first in a veritable Wild West of proprietary standards and passive injectors, then in a standardized process. Recently [T. K. Hareendran] wrote a primer on PoE, with more of a DIY intro focus, including some favorite PoE PD (powered device) chips to use in your own design.

You can still totally use passive PoE if that’s your jam, and you have full control over the network and any connected devices. This would allow you to, for example, power your SBCs for a couple of bucks, although for adding PoE to your Mac Mini you may want to look at some more refined options, if only as a safety precaution.

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The Fascinating Waveguide Technology Inside Meta’s Ray-Ban Display Glasses

October 9, 2025 by Maya Posch 27 Comments

The geometric waveguide glass of the Meta Ray-Ban Display glasses. (Credit iFixit)

Recently the avid teardown folk over at iFixit got their paws on Meta’s Ray-Ban Display glasses, for a literal in-depth look at these smart glasses. Along the way they came across the fascinating geometric waveguide technology that makes the floating display feature work so well. There’s also an accompanying video of the entire teardown, for those who enjoy watching a metal box cutter get jammed into plastic.

Overall, these smart glasses can be considered to be somewhat repairable, as you can pry the arms open with a bit of heat. Inside you’ll find the 960 mWh battery and a handful of PCBs, but finding spare parts for anything beyond perhaps the battery will be a challenge. The front part of the glasses contain the antennae and the special lens on the right side that works with the liquid crystal on silicon (LCoS) projector to reflect the image back to your eye.

While LCoS has been used for many years already, including Google Glass, it’s the glass that provides the biggest technological advancement. Instead of the typical diffractive waveguide it uses a geometric reflective waveguide made by Schott, with the technology developed by Lumus for use in augmented reality (AR) applications. This is supposed to offer better optical efficiency, as well as less light leakage into or out of the waveguide.

Although definitely impressive technology, the overall repairability score of these smart glasses is pretty low, and you have to contest with both looking incredibly dorky and some people considering you to be a bit of a glasshole.

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Why Stepper Motors Still Dominate 3D Printing

October 8, 2025 by Maya Posch 43 Comments

It’s little secret that stepper motors are everywhere in FDM 3D printers, but there’s no real reason why you cannot take another type of DC motor like a brushless DC (BLDC) motor and use that instead. Interestingly, some printer manufacturers are now using BLDCs for places where the reduction in weight matters, such as in the tool head or extruder, but if a BLDC can be ‘stepped’ much like any stepper motor, then why prefer one over the other? This is the topic of a recent video by [Thomas Sanladerer], with the answer being mostly about cost, and ‘good enough’ solutions.

The referenced driving method of field-oriented control (FOC), which also goes by the name of vector control, is a VFD control method in which the controller can fairly precisely keep position much like a stepper motor, but without the relatively complex construction of a stepper motor. Another advantage is that FOC tends to use less power than alternatives.

Using a FOC controller with a BLDC is demonstrated in the video, which also covers the closed-loop nature of such a configuration, whereas a stepper motor is generally driven in an open-loop fashion. Ultimately the answer at this point is that while stepper motors are ‘good enough’ for tasks where their relatively large size and weight aren’t real issues, as BLDCs with FOC or similar becomes more economical, we may see things change there.

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Building The DVD Logo Screensaver With LEGO

October 8, 2025 by Maya Posch 9 Comments

The completed Lego DVD screensaver. (Credit: Grant Davis, YouTube)

There’s something extremely calming and pleasing about watching a screensaver that merely bounces some kind of image around, with the DVD logo screensaver of a DVD player being a good example. The logical conclusion is thus that it would be great to replicate this screensaver in Lego, because it’d be fun and easy. That’s where [Grant Davis]’s life got flipped upside-down, as this turned out to be anything but an easy task in his chosen medium.

Things got off on a rocky start with figuring out how to make the logo bounce against the side of the ‘screen’, instead of having it merely approach before backing off. The right approach here seemed to be Lego treads as used on e.g. excavators, which give the motion that nice pause before ‘bouncing’ back in the other direction.

With that seemingly solved, most of the effort went into assembling a functional yet sturdy frame, all driven by a single Lego Technic electromotor. Along the way there were many cases of rapid self-disassembly, ultimately leading to a complete redesign using worm gears, thus requiring running the gears both ways with help from a gearbox.

Since the screensaver is supposed to run unattended, many end-stop and toggle mechanisms were tried and discarded before settling on the design that would be used for the full-sized build. Naturally, scaling up always goes smoothly, so everything got redesigned and beefed up once again, with more motors added and multiple gearbox design changes attempted after some unfortunate shredded gears.

Ultimately [Grant] got what he set out to do: the DVD logo bouncing around on a Lego ‘TV’ in a very realistic fashion, set to the noise of Lego Technic gears and motors whirring away in the background.

Thanks to [Carl Foxmarten] for the tip.

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Building A Diwheel To Add More Tank Controls To Your Commute

October 7, 2025 by Maya Posch 19 Comments

It’s often said that one should not reinvent the wheel, but that doesn’t mean that you cannot change how the use of said wheel should be interpreted. After initially taking the rather zany concept of a monowheel for a literal ride, [Sam Barker] decided to shift gears, did a ‘what if’ and slapped a second monowheel next to the first one to create his diwheel vehicle. Using much thicker steel for the wheels and overall much more robust construction than for his monowheel, the welding could commence.

It should be said here that the concept of a diwheel, or dicycle, isn’t entirely new, but the monowheel – distinct from a unicycle – is much older, with known builds at least as far back as the 19th century. Confusing, self-balancing platforms like Segways are also referred to as ‘dicycles’, while a diwheel seems to refer specifically to what [Sam] built here. That said, diwheels are naturally stable even without gyroscopic action, which is definitely a big advantage.

The inner frame for [Sam]’s diwheel is built out of steel too, making it both very robust and very heavy. High-tech features include suspension for that smooth ride, and SLS 3D-printed nylon rollers between the inner frame and the wheels. After some mucking about with a DIY ‘lathe’ to work around some measurement errors, a lot more welding and some questionable assembly practices, everything came together in the end.

This is just phase one, however, as [Sam] will not be installing pedals like it’s an old-school monowheel. Instead it’ll have electrical drive, which should make it a bit less terrifying than the Ford Ka-based diwheel we featured in 2018, but rather close to the electric diwheel called EDWARD which we featured back in 2011. We hope to see part two of this build soon, in which [Sam] will hopefully take this beast for its first ride.

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