Need A Curved Plastic Mesh? Print Flat, Curve Later

January 30, 2026 by Donald Papp 8 Comments

Need a plastic mesh in a custom pattern? 3D print it, no problem. But what if one needs a curved plastic mesh? That’s considerably harder to 3D print, but [Uncle Jessy]’s figured out a simple approach: 3D print the mesh flat, then break out a mold and a heat gun.

Of course, there are a few gotchas, but [Uncle Jessy] shares his tips for getting the most reliable results. The important part is to design and 3D print a mold that represents the final desired shape. Then print the mesh, and fit it into a frame. Heat things up with a heat gun, and press into the mold to deform the mesh while it’s still soft. It’s much easier seen than explained, so take a few moments to check out the video, embedded below the page break.

Because the plastic in a mesh is so thin, [Uncle Jessy] says to keep the heat low and slow. The goal is to have the mesh stretch and deform, not melt.

Speaking of heat, when thermoforming, one usually needs to make the mold out of heat-resistant material. But the thermal mass of a mesh is so small that it really doesn’t matter much — there just isn’t enough heat trapped in the mesh to really damage a mold. As long as the mold is reasonably dense, there’s no need to go overboard with making it heat resistant.

The whole process takes a little practice, but since the meshes are so fast to print and use so little plastic it’s easy to experiment a little.

As for the meshes themselves, a simple way to print a mesh is just to print a disc with no top or bottom layers, only infill. Set the infill pattern to honeycomb, for example, for an easy hexagon mesh. We’ve seen a variant of this “exposed infill” idea used to create a desiccant container, and using it to print a mesh pattern easily is a neat trick, too.

Why might one need to reshape a mesh into a curve? Perhaps to custom-fit a costume piece, or make custom eye inserts for masks, as shown here. In any case, it’s a good technique to keep in the back of one’s mind, and if you put it to good use, drop us a tip!

Continue reading “Need A Curved Plastic Mesh? Print Flat, Curve Later” →

Do Expensive Filaments Make 3D Printed Wrenches Better?

January 30, 2026 by Donald Papp 39 Comments

What filament is strongest? The real answer is “it depends”, but sometimes you have a simple question and you just want a simple answer. Like, which material makes the best 3D printed wrench? [My Tech Fun] printed a bunch of options to find out — including some expensive filaments — and got some interesting insights in the process.

His setup is simple: he printed a bunch of 13 mm open-end wrenches, and tested each one to failure by cranking on a clamped digital torque meter until the wrench failed by breaking, or skipping.

[My Tech Fun] tested a total of eighteen filaments, from regular basic PLA, PETG, ABS and ASA, and a variety of carbon fiber-infused filaments including PPA-CF. TPU is included for fun, and there’s also a wrench printed with continuous carbon fiber, which requires a special printer. More on that in a moment. First, let’s get to the results!

Unsurprisingly, TPU fared the worst at 0.8 nM which is roughly “unscrewing the cap of a water bottle” territory. Top performers included the wrench printed with continuous carbon fiber reinforcement (failing at 3.7 nM) and a couple printed in expensive PPA-CF (high-temperature nylon filament with carbon fiber) topped the list at 4.3 nM. Everything else landed somewhere in between, with plain PLA surprisingly outperforming some CF blends.

The continuous carbon fiber wrench was printed on a FibreSeeker printer, which reinforces a print with solid fibers embedded into the plastic instead of chopped particles, and such prints are noticeably more resistant to bending. Check out our earlier coverage for a closer look at what the FibreSeeker does.

This is a good time to mention that the wrench 3D model used is not at all optimized for best results with 3D printing. But that’s okay; this is really about the filaments, not the wrench.

The wrench model is just a way to test things in a familiar and highly visual, relatable way. You can see each one in action in the video below, and seeing [My Tech Fun] turn the wrenches gives a very good idea of just how much force is involved, with a relatable display of just how strong the different filaments are.

Continue reading “Do Expensive Filaments Make 3D Printed Wrenches Better?” →

These Ultra-Cute, Handsfree Walkie-Talkies Are Built For Cycling

January 29, 2026 by Donald Papp 16 Comments

Walkie-talkies are great fun, and [RealCorebb]’s bbTalkie project takes the concept a step further by adding some extremely cool features to make a highly refined, self-contained ESP32-based communicator. bbTalkie completely does away with a push-to-talk button by implementing robust voice detection that works reliably even in noisy environments. It was all designed with cycling in mind, so hands-free operation that stands up to noise is a big plus.

Hands-free, wireless, self-contained digital walkie-talkies that can connect in a group. What’s not to like?

The core of communication is done over ESP-NOW, which is Espressif’s own protocol for direct device-to-device broadcasting. This removes the need to involve any sort of external service like SIM cards or internet access to transmit voice. Performance is best with an external antenna, naturally, but ESP-NOW doesn’t actually require anything other than the existing on-board hardware.

We’ve seen ESP-NOW used to make digital walkie-talkies before, but bbTalkie is a really evolved take on the concept, not least of which due to its hands-free operation.

Because volume-based automatic triggers are highly susceptible to noise, voice detection is done with the help of VADNet, a neural network-based model implemented locally on the device. This system can reliably detect human speech, even in noisy environments. This lets bbTalkie switch between transmit and listen modes automatically and hands-free, without false triggers.

Even when doing all that, there’s still spare capability to play with. Further to the goal of making bbTalkie useful for cyclists in a group, [RealCorebb] added a system that can recognize specific voice commands (like “turn left” for example, or “wait for me!”) which trigger synchronized animations to play on the displays of all connected units. There’s even some experimental support for controlling a camera over Bluetooth, though currently it only supports hardware from Sony.

Watch a tour of it in the video below (Chinese language, English captions available). The OLED screens and animations are adorable, and are great visual feedback of what the unit is doing at any given moment.

Continue reading “These Ultra-Cute, Handsfree Walkie-Talkies Are Built For Cycling” →

Make Your Own ESP32-Based Person Sensor, No Special Hardware Needed

January 28, 2026 by Donald Papp 23 Comments

Home automation with high usefulness and low annoyance tends to rely on reliable person sensing, and [francescopace]’s ESPectre shows one way to do that cheaply and easily by leveraging hardware that’s already present on a common dev board.

ESPectre is an ESP32-based open source motion detector that detects movement without any cameras or microphones. It works similarly to millimeter-wave (mmWave) radar motion detectors in the sense that when a person moves, wireless signals are altered slightly as a result. ESPectre can detect this disturbance by watching and analyzing the Wi-Fi channel state information (CSI) and doing some very smart math and filtering. It’s cheap, easy to deploy and use, and even integrates with Home Assistant.

Combining a sensor like this with something else like a passive infrared (PIR) motion sensor is one way to get really robust results. But keep in mind that PIR only senses what it can see, whereas ESPectre works on WiFi, which can penetrate walls.

Since ESPectre supports low-cost ESP32 variants and is so simple to get up and running, it might be worth your time to give it a trial run. There’s even a browser-based ghost-dodging game [francescopace] put online that uses an ESPectre board plugged in over USB, which seems like a fun way to get a feel for what it can do.

DIY Magnetic Markers Help 3D Scan Tricky Objects

January 20, 2026 by Donald Papp 6 Comments

3D scanners rely on being able to identify physical features of an object, and line up what it saw a moment ago with what it sees now in order to build a 3D model. However, not every object is as distinct and visible as others at all angles, particularly in IR. One solution is reflective scanning markers, which are either pre-printed on a mat, or available as stickers that can be applied to objects to give the scanner a bit more to latch onto, visually speaking.

[firstgizmo] shows a slightly different approach: that of surrounding the object to be scanned with 3D printed reflective markers instead of covering the target object itself with reflectors, or relying on a flat scanning mat.

Magnetic mounts allow mixing and matching, as well as attaching directly to some objects to be scanned.

The main advantage (besides not having to remove stickers from the object afterwards) is that these printed markers present the reflective dots at a variety of angles during the scanning process. This makes the scene less sensitive to scanner angle in general, which is good because the angle at which to scan an important feature of an object is not always the angle that responds best.

By giving the scene more structure, the scanner can have a better shot at scanning reliably even if the reflectors aren’t on the target object itself. It also helps by making it easier to combine multiple scans. The more physical features scans have in common, the easier it is to align them.

Just to be clear, using these means one will, in effect, be 3D scanning the markers along with the target object. But once all the post-processing is done, one simply edits the model to remove everything except the target object.

[firstgizmo]’s DIY magnetic 3D scanning markers are an expanded take on an idea first presented by [Payo], who demonstrates the whole concept wonderfully in the video below.

3D scanning can be tremendously handy but it does have its quirks and limitations, and a tool like this can be the difference between a terrible scan and a serviceable one. For a quick catch-up on 3D scanning and its strengths and limitations, read our hands-on tour of using an all-in-one 3D scanner.

Continue reading “DIY Magnetic Markers Help 3D Scan Tricky Objects” →

Flux And Solder Paste Dispenser Looks Good While Doing It

January 19, 2026 by Donald Papp 10 Comments

Syringes are pretty ergonomic, but when manually dispensing flux and solder paste it doesn’t take long before one wants a better way. [Elektroarzt]’s flux and solder paste dispenser design uses 3D-printed parts and minimal hardware (mostly M3x20 screws, and an optional spring) to improve handling and control.

The operating principle is very similar to how a hot glue gun feeds a stick of glue.

How does it work? The ratcheting lever mechanism is similar to that of a hot glue gun, where an arm slips into notches in a rod when pressed down, driving it forward and never backward. In the process, a larger lever movement is translated into a shorter plunger travel, enhancing control.

The types of syringes this tool is meant to be used with have a plunger tip or piston (the rubber stopper-looking part, in contact with the liquid) inside the loaded syringe, but no plunger shaft attached to it. This is common with syringes meant to be loaded into tools or machines, and [Elektroarzt]’s tool can be used with any such syringe in a 10 cc size.

It’s an attractive design, and we like the way syringes top-load as well as the way the tool is made to lay flat on a tabletop, with the lever pointed up.

Want truly fine-grained control over your extrusions? Then check out this dispenser which really lets one dial in small amounts. You can also go motorized, and let a small PCB and stepper motor do the work.

Print Your Own Standardized Wire Spool Storage

January 2, 2026 by Donald Papp 22 Comments

Hardware hackers tend to have loads of hookup wire, and that led [firstgizmo] to design a 3D printable wire and cable spool storage system. As a bonus, it’s Gridfinity-compatible!

The slot to capture loose ends is a nice touch, and the units can be assembled without external hardware.

There are a lot of little design touches we love. For example, we like the little notch into which the wire ends are held, which provides a way to secure the loose ends without any moving parts. Also, while at first glance these holders look like something that goes together with a few screws, they actually require no additional hardware and can be assembled entirely with printed parts. But should one wish to do so, [firstgizmo] has an alternate design that goes together with some M3 bolts instead.

Want to adjust something? The STEP files are included, which we always love to see because it makes modifications to the models so much more accessible. One thing that hasn’t changed over the years is that making engineering-type adjustments to STL files is awful, at best.

If there is one gotcha, it is that one must remove wire from their old spools and re-wind onto the new to use this system. However, [firstgizmo] tries to make that as easy as possible by providing two tools to make re-spooling easier: one for hand-cranking, and one for using a hand drill to do the work for you.

It’s a very thoughtful design, and as mentioned, can also be used with the Gridfinity system, which seems to open organizational floodgates in most people’s minds. Most of us are pinched for storage space, and small improvements in space-saving really, really add up.