Necroprinting Isn’t As Bad As It Sounds

December 1, 2025 by Lewin Day 18 Comments

A mosquito has a very finely tuned proboscis that is excellent at slipping through your skin to suck out the blood beneath. Researchers at McGill University recently figured that the same biological structure could also prove useful in another was—as a fine and precise nozzle for 3D printing (via Tom’s Hardware).

Small prints made with the mosquito proboscis nozzle. Credit: research paper

To achieve this feat, the research team harvested the proboscis from a female mosquito, as only the female of the species sucks blood in this timeline. The mosquito’s proboscis was chosen over other similar biological structures, like insect stingers and snake fangs. It was prized for its tiny size, with an inside diameter of just 20 micrometers—which outdoes just about any man-made nozzle out there. It’s also surprisingly strong, able to resist up to 60 kPa of pressure from the fluid squirted through it.

Of course, you can’t just grab a mosquito and stick it on your 3D printer. It takes very fine work to remove the proboscis and turn it into a functional nozzle; it also requires the use of 3D printed scaffolding to give the structure additional strength. The nozzle is apparently used with bio-inks, rather than molten plastic, and proved capable of printing some basic 3D structures in testing.

Amusingly, the process has been termed 3D necroprinting, we suspect both because it uses a dead organism and because it sounds cool on the Internet. We’ve created a necroprinting tag, just in case, but we’re not holding our breath for this to become the next big thing. At 20 um, more likely the next small thing.

Further details are available in the research paper. We’ve actually featured quite a few mosquito hacks over the years. Video after the break.

Continue reading “Necroprinting Isn’t As Bad As It Sounds” →

How To Print PETG As Transparently As Possible

November 29, 2025 by Lewin Day 6 Comments

PETG filament can be had in a variety of colors, just like any other. You can even get translucent or transparent forms if you want to print something vaguely see-through. But if you’re looking for a bit more visually impressive, you might like to pick up a few tips from [Tej Grewal] on making sure your prints come out as clear as possible.

Standard print settings aren’t great for transparency.

It all comes down to pathing of the 3D printer’s hot end. If it’s zigzagging back and forth, laying down hot plastic in all different orientations from layer to layer, you’re going to get a hazy, ugly, result that probably doesn’t look very see-through at all.

However, you can work around this by choosing slicer settings that make the tool pathing more suitable for producing a clearer part. [Tej] recommends going slow — as little as 20 mm/s during printing. He also states that removing top and bottom shells and setting wall loops to 1 can help to produce a part that’s entirely infill. Then, you’ll want to set infill to 100% and the direction to 0 or 90 degrees. This will ensure your hot end is just making long, straight strokes for layer after layer that will best allow light to pass through. You’ll also want to maximize nozzle flow to avoid any unsightly gaps or bubbles in your print.

[Tej] demonstrates the technique by creating a cover for a display. By using the settings in question, he creates a far more transparent plate, compared to the original part that has an ugly zig-zagging haze effect. You’re not going to get something optically clear this way; the final results are more lightly frosted, but still good.

Transparency will never be something 3D printers are great at. However, we have seen some interesting post-processing techniques that will blow your mind in this regard.

3D printed jaw with fake muscle attached

3D Printing For The Hospital Setting

November 28, 2025 by Ian Bos 9 Comments

Surgery is hard, there is a reason why school is so long for the profession. Making the job easier and smoother for both patients and surgeons is valuable for all parties, which is why [Mayo Clinic] is now working on including 3D printing into its more regular medicine pipeline.

Prepping for surgery often requires examining CT scans of patients to figure out, well, what they’re even going to be doing. Every body is different, and complex surgical procedures require checking to see where certain organs or features are located. This can be made much easier with a physical model of where the bones, organs, or nerves are specifically located in a patient. While this isn’t true in every case of treatment, there are even cancerous cases where custom equipment can be used to decrease side effects, such as mini-beam collimator adapters.

What if you could use the same pipeline to print what was lost from certain procedures? In a mastectomy, the breast tissue is removed, which can cause negative attention from curious gazes. So why not 3D print a custom breast? Cases like these are generally considered poor commercial investments from industry, but are relatively easy for an existing medical facility to add to treatment.

[Mayo Clinic] is far from the first to consider 3D printing in the medical setting, but seeing the technology see actual applied use rather than future seeking is exciting. Medical hacking is always exciting, and if you want to see more examples, keep sure to check out this commercially available simulator (with some free models).

Designing PLA To Hold Over A Metric Ton

November 27, 2025 by Ian Bos 13 Comments

There’s never been such a thing as being “too competitive” when it comes to competition. This is something that [Tom Stanton] from “Tim Station”, [Tom]’s 2nd channel, took to heart for Polymaker’s 3D design challenge. The goal was simple: a single 3D printed part to hold as much weight as possible.

While seemingly simple, when considering the requirements, including a single print in addition to being able to open up for the mounts, the challenge gets exponentially more complicated. While the simplest and strongest joint would be a simple oval for uniform stress, this isn’t possible when considering the opening requirements. This creates a need for slightly more creativity.

[Tom] starts out with two flat C-shaped geometries to test his design. The design includes teeth specially placed to allow the forces to increase their own strength as force is applied. Flat features have the unfortunate quality of being able to slide across each other rather easily, which was the case during testing; however, the actual structures held up rather well. Moving onto the final design, including a hollow cavity and a much thicker depth, showed good promise early on in the competition, leading up to the finals. In fact, the design won out over anything else, getting over double the max strength of the runner up. Over an entire metric ton, the piece of plastic proved its abilities far past anything us here at Hackaday would expect from a small piece of PLA.

Design can be an absolute rabbit hole when it comes to even the simplest of things, as shown with this competition. [Tom] clearly showed some personal passion for this project; however, if you haven’t had the chance to dive this deep into CADing, keep sure to try out something like TinkerCAD to get your feet wet. TinkerCAD started out simple as can be but has exploded into quite the formidable suite!

Continue reading “Designing PLA To Hold Over A Metric Ton” →

Rare Filament Makes Weird Benchies

November 20, 2025 by Al Williams 22 Comments

[Zack], in addition to being a snappy dresser, has a thing for strange 3D printing filament. How strange? Well, in a recent video, he looks at filaments that require 445 C. Even the build plate has to be super hot. He also looks at filament that seems like iron, one that makes you think it is rubber, and a bunch of others.

As you might expect, he’s not using a conventional 3D printer. Although you might be able to get your more conventional printer to handle some of these, especially with some hacking. There is filament with carbon fiber, glass fiber, and more exotic add-ons.

Most of the filaments need special code to get everything working. While you might think you can’t print these engineering filaments, it stands to reason that hobby-grade printers are going to get better over time (as they already have). If the day is coming when folks will be able to print any of these on their out-of-the-box printer, we might as well start researching them now.

If you fancy a drinking game, have a shot every time he changes shots and a double when the Hackaday Prize T-shirt shows up.

Continue reading “Rare Filament Makes Weird Benchies” →

Casting Metal Tools With Kitchen Appliances

November 18, 2025 by Bryan Cockfield 23 Comments

Perhaps the biggest hurdle to starting a home blacksmithing operating is the forge. There’s really no way around having a forge; somehow the metal has to get hot enough to work. Although we might be imagining huge charcoal- or gas-fired monstrosities, [Shake the Future] has figured out how to use an unmodified, standard microwave oven to get iron hot enough to melt and is using it in his latest video to cast real, working tools with it. (Also available to view on Reddit)

In the past, [Shake the Future] has made a few other things with this setup like an aluminum pencil with a graphite core. This time, though, he’s stepping up the complexity a bit with a working tool. He’s decided to build a miniature bench vice, which uses a screw to move the jaws. He didn’t cast the screw, instead using a standard size screw and nut, but did cast the two other parts of the vice. He first 3D prints the parts in order to make a mold that will withstand the high temperatures of the molten metal. With the mold made he can heat up the iron in the microwave and then pour it, and then with some finish work he has a working tool on his hands.

A microwave isn’t the only kitchen appliance [Shake the Future] has repurposed for his small metalworking shop. He also uses a standard air fryer in order to dry parts quickly. He works almost entirely from the balcony of his apartment so he needs to keep his neighbors in mind while working, and occasionally goes to a nearby parking garage when he has to do something noisy. It’s impressive to see what can be built in such a small space, though. For some of his other work be sure to check out how he makes the crucibles meant for his microwave.

Continue reading “Casting Metal Tools With Kitchen Appliances” →

Camera Capabilities Unlocked From A Mouse

November 8, 2025 by Ian Bos 21 Comments

There is a point where taking technology for granted hides some of the incredible capabilities of seemingly simple devices. Optical mice are a great example of this principle, using what are more or less entirely self-contained cameras just for moving the cursor across your screen. Don’t believe us? Check out this camera made from an old optical mouse from [Dycus]!

For those unfamiliar with optical mice, the sensor used for tracking movement, like a camera, is just an array of photosensitive sensors. This allows a simple on-board microcontroller to convert the small changes from the visual sensor into acceleration/movement information to be sent to the computer.

Proving how capable these sensors can truly be, [Dycus]’s camera manages a whole 30×30 array of picture quality. Along with glorious greyscale, the pictures achieved from such a camera are more than recognizable. Putting together the camera didn’t even require anything crazy beyond the sensor itself. What appears to be a Teensy LC board, basic buttons, and a small screen are essentially everything required to replicate the camera’s functionality. Pictures, both standard and “panoramic”, can be viewed in a variety of color palettes stored on board. Along with a surprisingly impressive feature set, the idea is impressive.

Limitations are often the mother of innovation, no matter if self-imposed or not, as seen here. However, [Dycus] still had a whole 30×30 array to photograph. What about a single pixel? Let’s make it even harder; we can’t look directly at the subject! This is exactly what was done here in this impressive demonstration of clever engineering.

Thanks to JohnU and Thinkerer for the tip!