Butta Melta Stops Rock-solid Butter From Tearing Your Toast

August 25, 2025 by Donald Papp 24 Comments

Ever ruin a perfectly serviceable piece of toast by trying (and failing) to spread a little pat of rock-solid butter? [John Dingley] doesn’t! Not since he created the Butta Melta to cozily snug a single butter serving right up against a warm beverage, softening it just enough to get nice and spreadable. Just insert one of those foil-wrapped pats of butter into the Melta, hang its chin on the edge of your mug, and you’ll have evenly softened butter in no time.

The Butta Melta is intentionally designed with a bit of personality, but also has features we think are worth highlighting. One is the way it’s clearly designed with 3D printing in mind, making it an easy print on just about any machine in no time at all. The second is the presence of the hinge point which really helps the Butta Melta conform to a variety of cup designs, holding the payload as close as possible to the heat regardless of cup shape. A couple of minutes next to a hot beverage is all it takes for the butter to soften enough to become easily spreadable.

You may remember [John] (aka [XenonJohn]) from his experimental self-balancing scooters, or from a documentary he made about domestic ventilator development during COVID. He taught himself video editing and production to make that, and couldn’t resist using those skills to turn a video demo of the Butta Melta into a mock home shopping style advertisement. Watch it below, embedded just under the page break, then print one and save yourself from the tyranny of torn toast.

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LeRobot Brings Autonomy To Hobby Robots

August 23, 2025 by Donald Papp 6 Comments

Robotic arms have a lot in common with CNC machines in that they are usually driven by a fixed script of specific positions to move to, and actions to perform. Autonomous behavior isn’t the norm, especially not for hobby-level robotics. That’s changing rapidly with LeRobot, an open-source machine learning framework from the Hugging Face community.

The SO-101 arm is an economical way to get started.

If a quick browse of the project page still leaves you with questions, you’re not alone. Thankfully, [Ilia] has a fantastic video that explains and demonstrates the fundamentals wonderfully. In it, he shows how LeRobot allows one to train an economical 3D-printed robotic arm by example, teaching it to perform a task autonomously. In this case, the task is picking up a ball and putting it into a cup.

[Ilia] first builds a dataset by manually operating the arm to pick up a ball and place it in a cup. Then, with a dataset consisting of only about fifty such examples, he creates a machine learning model capable of driving the arm to autonomously pick up a ball and place it in a cup, regardless of where the ball and cup actually are. It even gracefully handles things like color changes and [Ilia] moving the cup and ball around mid-task. You can skip directly to 34:16 to see this autonomous behavior in action, but we do recommend watching the whole video for a highly accessible yet deeply technical overview.

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RepRapMicron Promises Micro-fabrication For Desktops With New Prototype

August 22, 2025 by Donald Papp 15 Comments

3D printing has transformed how hobbyists fabricate things, but what additional doors would open if we could go even smaller? The µRepRap (RepRapMicron) project aims to bring fabrication at the micron and sub-micron scale to hobbyists the same way RepRap strove to make 3D printing accessible. New developments by [Vik Olliver] show a promising way forward, and also highlight the many challenges of going so small.

How exactly would a 3D printer do micro-fabrication? Not by squirting plastic from a nozzle, but by using a vanishingly tiny needle-like effector (which can be made at any workbench via electrochemical erosion) to pick up a miniscule amount of resin one dab a time, curing it with UV after depositing it like a brush deposits a dot of ink.

By doing so repeatedly and in a structured way, one can 3D print at a micro scale one “pixel” (or voxel, more accurately) at a time. You can see how small they’re talking in the image in the header above. It shows a RepRapMicron tip (left) next to a 24 gauge hypodermic needle (right) which is just over half a millimeter in diameter.

Moving precisely and accurately at such a small scale also requires something new, and that is where flexures come in. Where other 3D printers use stepper motors and rails and belts, RepRapMicron leverages work done by the OpenFlexure project to achieve high-precision mechanical positioning without the need for fancy materials or mechanisms. We’ve actually seen this part in action, when [Vik Olliver] amazed us by scribing a 2D micron-scale Jolly Wrencher 1.5 mm x 1.5 mm in size, also visible in the header image above.

Using a tiny needle to deposit dabs of UV resin provides the platform with a way to 3D print, but there are still plenty of unique problems to be solved. How does one observe such a small process, or the finished print? How does one handle such a tiny object, or free it from the build platform without damaging it? The RepRapMicron project has solutions lined up for each of these and more, so there’s a lot of discovery waiting to be done. Got ideas of your own? The project welcomes collaboration. If you’d like to watch the latest developments as they happen, keep an eye on the Github repository and the blog.

One-Motor Drone Mimics Maple Seeds For Stability

August 20, 2025 by Donald Papp 14 Comments

We’ve seen aircraft based on “helicopter” seeds (technically samara seeds, which include those of maples and elms) before, but this recent design from researchers at the Singapore University of Technology and Design (SUTD) shows how a single small motor can power a spinning monocopter capable of active directed flight, including hovering.

The monocopter is essentially an optimized wing shape with a single motor and propeller at one end. Hardware-wise it might be simple, but the tradeoff is higher complexity in other areas. Physical layout and balance are critical to performance, and software-wise controlling what is basically a wing spinning itself at high speed is a complex task. The payoff is highly-efficient flight in a package that self-stabilizes; it weighs only 32 grams and has a flight time of 26 minutes, which is very impressive for a self-contained micro aircraft.

We saw what looks like an earlier version of this concept from SUTD that was capable of directed flight by modifying the airfoil surface, but like the seeds it was modeled after, it’s more of a glider. This unit has the same spinning-seed design, but is actively powered. A significant improvement, for sure.

For those who prefer their DIY micro aircraft a little more traditional-looking, be sure to check out the design details of a handmade and fully operational 1:96 scale P-51 Mustang that weighs only 2.9 grams. It even has retractable landing gear! When one can manage to keep mass to a bare minimum, a little power goes a long way.

Hide Capacitive Touch Buttons In Your Next 3D Print

August 20, 2025 by Donald Papp 15 Comments

Capacitive touch sensors are entirely in the domain of DIY, requiring little more than a carefully-chosen conductive surface and a microcontroller. This led [John Phillips] to ask why not embed such touch buttons directly into a 3D print?

Button locations and labels can be made as part of the 3D print, which is handy.

The process is not much different from that of embedding hardware like magnets or fasteners into 3D prints: one pauses the print at convenient spot, drops in the necessary hardware, then resumes printing. It’s more or less the same for embedding a touch-sensitive button, but [John] has a few tips to make things easier.

[John] suggests using a strip of copper tape, one per touch pad, and embedding it into the print near the surface. His preference is three layers in, putting the copper tape behind 0.6 mm of plastic when using standard 0.20 mm layer heights.

Copper tape makes a good capacitive touch sensor, and the adhesive on the tape helps ensure it stays in place as the 3D printer seals it in on subsequent passes.

Copper tape is also easy to solder to, so [John] leaves a small hole over the copper — enough to stick in a wire and tack it down with the tip of a soldering iron and a blob of solder after the print is complete. It might not be ideal soldering conditions, but if things get a little melty on the back side it’s not the end of the world.

On the software side capacitive touch sensors can be as simple as using an Arduino library for the purpose but [John] rolled his own code, so give it a peek.

This reminds us a bit of another way to get a capacitive touch sensor right up against some plastic: a simple spring can do the trick.

OpenAI Releases Gpt-oss AI Model, Offers Bounty For Vulnerabilities

August 6, 2025 by Donald Papp 11 Comments

OpenAI have just released gpt-oss, an AI large language model (LLM) available for local download and offline use licensed under Apache 2.0, and optimized for efficiency on a variety of platforms without compromising performance. This is their first such “open” release, and it’s with a model whose features and capabilities compare favorably to some of their hosted services.

OpenAI have partnered with ollama for the launch which makes onboarding ridiculously easy. ollama is an open source, MIT-licensed project for installing and running local LLMs, but there’s no real tie-in to that platform. The models are available separately: gpt-oss-20b can run within 16 GB of memory, and the larger and more capable gpt-oss-120b requires 80 GB. OpenAI claims the smaller model is comparable to their own hosted o3-mini “reasoning” model, and the larger model outperforms it. Both support features like tool use (such as web browsing) and more.

LLMs that can be downloaded and used offline are nothing new, but a couple things make this model release a bit different from others. One is that while OpenAI have released open models such as Whisper (a highly capable speech-to-text model), this is actually the first LLM they have released in such a way.

The other notable thing is this release coincides with a bounty challenge for finding novel flaws and vulnerabilities in gpt-oss-20b. Does ruining such a model hold more appeal to you than running it? If so, good news because there’s a total of $500,000 to be disbursed. But there’s no time to waste; submissions need to be in by August 26th, 2025.

Brilliant Labs Has New Smart Glasses, With A New Display

August 4, 2025 by Donald Papp 15 Comments

Brilliant Labs have been making near-eye display platforms for some time now, and they are one of the few manufacturers making a point of focusing on an open and hacker-friendly approach to their devices. Halo is their newest smart glasses platform, currently in pre-order (299 USD) and boasting some nifty features, including a completely new approach to the display.

Development hardware for the Halo display. The actual production display is color, and integrated into the eyeglasses frame.

Halo is an evolution of the concept of a developer-friendly smart glasses platform intended to make experimentation (or modification) as accessible as possible. Compared to previous hardware, it has some additional sensors and an entirely new approach to the display element.

Whereas previous devices used a microdisplay and beam splitter embedded into a thick lens, Halo has a tiny display module that one looks up and into in the eyeglasses frame. The idea appears to be to provide the user with audio (bone-conduction speakers in the arms of the glasses) as well as a color “glanceable” display for visual data.

Some of you may remember Brilliant Labs’ Monocle, a transparent, self-contained, and wireless clip-on display designed with experimentation in mind. The next device was Frame, which put things into a “smart glasses” form factor, with added features and abilities.

Halo, being in pre-release, doesn’t have full SDK or hardware details shared yet. But given Brilliant Labs’ history of fantastic documentation for their hardware and software, we’re pretty confident Halo will get the same treatment. Want to know more but don’t wish to wait? Checking out the tutorials and documentation for the earlier devices should give you a pretty good idea of what to expect.