The main mechanical tools in a hacker’s shop used to be a drill press and a lathe. Maybe a CNC mill, if you were lucky. Laser cutters are still a rare tool to find in a personal shop, but today’s hackers increasingly have access to 3D printers. What happens when you have a design for a laser cutter (2D parts) but only have access to a 3D printer? You punt.
[DIY3DTECH] has a two-part video on taking a 2D design (in an SVG file) and bringing it into TinkerCad. At that point, he assembles the part in software and creates a printable object. You can see the videos below.
Here at Hackaday, we love clever 3D prints. This amazing lion statue remixed by [ _primoz_], makes us feel no different. It is no secret that FDM 3D printers have come a long way, propelled by the enthusiastic support from the open source community.
However, FDM 3D printers have some inherent limitations; some of which arise from a finite print nozzle diameter, tracing out the 3D object layer by layer. Simply put, some print geometries and dimensions are just unattainable. We discussed the solution to traditional FDM techniques being confined to Planer layers only in a previous article.
The case in point here is a 3D printed lion whose original version did not fully capture its majestic mane. [_primoz_] solution was to construct a support cylinder around the head and form the actual hair as a series of planar bristles, which were one extrusion wide.
This was followed by some simple post processing, where a heat gun was used to form the bristles into a dapper mane.
The result is rather glorious and we can’t wait for someone to fire up a dual extruder and bring out the flexible filament for this print!
If you are a fan of sci-fi shows you’ll be used to volumetric 3D displays as something that’s going to be really awesome at some distant point in the future. It’s been about forty years since a virtual 3D [Princess Leia] was projected to Star Wars fans from [R2D2]’s not-quite-a-belly-button, while in the real world it’s still a technology with some way to go. We’ve seen LED cubes, spinning arrays, and lasers projected onto spinning disks, but nothing yet to give us that Wow! signaling that the technology has truly arrived.
We are starting to see these displays move from the high-end research lab into the realm of hackers and makers though, and the project we have for you here is a fantastic example. [Balduin Dettling] has created a spinning LED display using multiple sticks of addressable LEDs mounted on a rotor, and driven by a Teensy 3.1. What makes this all the more remarkable is that he’s a secondary school student at a Gymnasium school in Germany (think British grammar school or American prep school).
There are 480 LEDs in his display, and he addresses them through TLC5927 shift registers. Synchronisation is provided by a Hall-effect sensor and magnet to detect the start of each rotation, and the Teensy adjusts its pixel rate based on that timing. He’s provided extremely comprehensive documentation with code and construction details in the GitHub repository, including a whitepaper in English worth digging into. He also posted the two videos we’ve given you below the break.
What were you building in High School? Did it involve circuit design, mechanical fabrication, firmware, and documentation? This is an impressive set of skills for such a young hacker, and the type of education we like to see available to those interested in a career in engineering.
There’s an especially large focus on 3D displays. Projecting onto screens, droplets of water, spinning objects, and even plasma combustion are covered. But so are the funny physical displays: flip-dots, pin-cushions, and even servo-driven “pixels”.
We really liked the section on LCDs with modified polarization layers — we’ve seen some cool hacks using that gimmick, but the art pieces he dredged up look even better. Makes us want to take a second look at that busted LCD screen in the basement.
We’re big fans of the bright and blinky, so it’s no surprise that [Blair] got a bunch of his examples from these very pages. And we’ve covered [Blair]’s work as well: both his Wobbulator and his “Color a Sound” projects. Hackaday: your one-stop-shop for freaky pixels.
[Blair]’s list looks pretty complete to us, but there’s always more out there. What oddball displays are missing? What’s the strangest or coolest display you’ve ever seen?
[Chris Gunawardena] is still holding his breath on Valve and Facebook surprising everyone by open sourcing their top secret VR prototypes. They have some really clever ways to track the exact location and orientation of the big black box they want people to strap to their faces. Until then, though, he decided to take his own stab at the 3D tracking problems they had to solve.
While they used light to perform the localization, he wanted to experiment with using electromagnetic fields to perform the same function. Every phone these days has a magnetometer built in. It’s used to figure out which way is up, but it can also measure the local strength of magnetic fields.
Unfortunately to get really good range on a magnetic field there’s a pesky problem involving inverse square laws. Some 9V batteries in series solved the high current DC voltage source problem and left him with magnetic field powerful enough to be detected almost ten centimeters away by his iPhone’s magnetometer.
As small as this range seems, it ended up being enough for his purposes. Using the existing math and a small iOS app he was able to perform rudimentary localization using EM fields. Pretty cool. He’s not done yet and hopes that a more sensitive magnetometer and a higher voltage power supply with let him achieve greater distances and accuracy in a future iteration.
[Jay] out of the River City Labs Hackerspace in Peoria, IL cleared out a jam in his printer. It’s an operation most of us who own a 3D printer have performed. He reassembled the nozzle, and in a moment forgot to tighten down the grub nut that holds the heater cartridge in place. He started a print, saw the first layer go down right, and left the house at 8:30 for work. When he came back from work at 10:30 he didn’t see the print he expected, but was instead greeted by acrid smoke and a burnt out printer.
As far as he can figure, some time at around the thirty minute mark the heater cartridge vibrated out of the block. The printer saw a drop in temperature and increased the power to the cartridge. Since the cartridge was now hanging in air and the thermistor that reads the temperature was still attached to the block, the printer kept sending power. Eventually the cartridge, without a place to dump the energy being fed to it, burst into flame. This resulted in the carnage pictured. Luckily the Zortrax is a solidly built full metal printer, so there wasn’t much fuel for the fire, but the damage is total and the fire could easily have spread.
Which brings us to the topics of discussion.
How much can we trust our own work? We all have our home-builds and once you’ve put a lot of work into a printer you want to see it print a lot of things. I regularly leave the house with a print running and have a few other home projects going 24/7. Am I being arrogant? Should I treat my home work with a lesser degree of trust than something built by a larger organization? Or is the chance about the same? Continue reading “Ask Hackaday MRRF Edition: 3D Printers Can Catch Fire”→
[Stefan] is building a fixed wing drone, and with that comes the need for special mounts and adapters for a GoPro. The usual way of creating an adapter is pulling out a ruler, caliper, measuring everything, making a 3D model, and sending it off to a 3D printer. Instead of doing things the usual way, [Stefan] is using photogrammetric 3D reconstruction to build a camera adapter that fits perfectly in his plane and holds a camera securely.
Photogrammetry requires taking a few dozen pictures with a camera, using software to turn these 2D images into a 3D model, and building the new part from that model. The software [Stefan] is using is Pix4D, a piece of software that is coincidentally used to create large-scale 3D models from drone footage.
With the 2D images turned into a 3D model, [Stefan] imported the .obj file into MeshLab where the model could be cropped, smoothed, and the file size reduced. From there, creating the adapter was as simple as a little bit of OpenSCAD and sending the adapter model off to a 3D printer.