These days, it’s common among us hackers to load a stepper motor with forces in-line with their shaft–especially when we couple them to leadscrews or worm gears. Unfortunately, steppers aren’t really intended for this sort of loading, and doing so with high forces can destroy the motor. Fear not, though. If you find yourself in this situation, [Voind Robot] has the solution for you with a dead-simple-yet-dead-effective upgrade to get your steppers tackling axial loads without issue.
In [Voind Robot’s] case, they started with a worm-gear-drive on a robot arm. In their circumstances, moving the arm could put tremendous axial loads onto the stepper shaft through the worm–as much as 30 Newtons. Such loads could easily destroy the internal stepper motor bearings in a short time, so they opted for some double-sided reinforcement. To alleviate the problem, the introduced two thrust bearings, one on either side of the shaft. These thrust bearings do the work of redirecting the force off the shaft and directly onto the motor casing, a much more rigid place to apply such loads.
This trick is dead simple, and it’s actually over five years old. Nevertheless, it’s still incredibly relevant today for any 3D printer builder who’s considering coupling a leadscrew to a stepper motor for their Z-axis. There, a single thrust bearing could take out any axial play and lead to an overall rigid build. We love simple machine-design nuggets of wisdom like these. If you’re looking for more printer-design tricks, look no further than [Moritz’s] Workhorse Printer article.
It’s been just over a year since E3D whetted our appetites for toolchanging printers. Now, with the impending release of their first toolchanging system, they’ve taken the best parts of their design and released them into the wild as open source. Head on over to Github for a complete solution to exchanging, locating, and parking tools on a 3D printer.
For anyone interested in fabricating the design, the files are in a format that you can almost re-zip and email to a manufacturer for quotes. As is, the repository offers STP-style CAD files, a complete set of dimensioned drawings, exploded views, and even a bill of materials. Taken as a whole, the system elegantly solves the classic problems that we’d encounter in toolchanging. Locking tools is done with a spring-based T-bar that swivels onto an wedge-shaped groove on the back of each tool plate. Locating tools is done so with a 3-groove kinematic coupling fabriacted from dowel pins. With these problems solved and presented so cleanly, these files become a path by which we can establish a common means for exchanging tools on 3D printer systems.
It’s worth asking: why develop an exceptional design and then release it for free? I’ll speculate that E3D has done an excellent job over the years establishing a well-recognized standard set of stock parts. Nearly every 3D printer builder is bound to have at least one spare V6 hotend sitting idle in a disassembled pool of former-3D-printers. With tool-changing positioned to become another step forward in the space of possibilities with 3D printing, setting the standard for tools early encourages the community to continue developing applications that lean on E3D’s ecosystem of parts.
In the last 30 years, 3D printing has transformed away from a patent-trolling duopoly to a community-friendly group of contributors that lean on each other’s shoulders with shared findings. It’s a kind gesture to the open-source community of machine builders to receive such a feature-complete mechanism. With that said, let’s start rolling the toolchanger hacks.
When it comes to wall-mounted ornamentation, get ready to throw out your throw-rugs and swap them for something that will pop so vividly, you’ll want to get your eyes checked. To get our eyes warmed up and popping, [James Best] has concocted a gargantuan 900-RGB-LED music visualizer to ensure that our bedrooms are bright and blinky on demand.
Like any other graduate from that small liberal-arts school in southern California, [James] started prototyping with some good old-fashioned blue tape. Once he had had his grid-spacing established, he set to work on 2-meter-by-0.5-meter wall mounted display from some plywood and lumber. Following some minor adhesive mishaps, James had his grid tacked down with Gaffers tape, and ready for visuals.
Under the hood, a Teensy is leveraging its DMA capabilities to conduct out a bitstream to 900 LEDs. By using the DMA feature and opting for a Teensy over the go-to Arduino, [James] is using the spare CPU cycles to cook out some Fourier-Transformed music samples and display their frequency content.
We’ve covered folks proving the concept of driving oodles of WS2812B LEDs over DMA; it’s great seeing these ideas mature into a fully-featured project that lands on the walll. For more on chatting with WS2812B LEDs over DMA, have a look back into our archive.
[Paul’s] 3D printer is a hat-tip to anyone who’s spent time in the wetlab. For starters, the printer is born from the remains of a former liquid handling system, a mighty surplus score. When it comes to headchanging, [Paul] combined some honest inspiration from E3D’s toolchanging videos with some design features borrowed from the microscope in his lab. The result is that the printer’s five-tool head-changer mechanically behaves very similarly to the nose piece in a compound light microscope.
Because the printer evolved from old lab equipment, [Paul] dubs his printer into a lineage that he calls the “Reclaimed Rapid-Prototyper,” or the RecRap. Best of all, he’s kindly posted up the CAD files on the Thingiverse such that you too can take a deep look into this head-changing solution.
We love seeing these tools get a second life, and we think there’s plenty of potential for new offspring in this lineage of discarded lab equipment.
In the 3D-printing community, [Mark Peeters] may be known-and-loved for his drooloop printing, but that’s not enough to stop him from pushing the spectrum of printing tricks even further. Dubbed Toolpath Painting, [Mark] is taking that glorious sheen from the bottom layer of a 3D print and putting it to work to make eye-catching deliberate visual displays.
[Mark’s] work comes in two flavors. The first capitalizes on a fairly wide 2mm nozzle and translucent filaments to create vibrant sun catchers. The second relies on the reflective patterns of an opaque filament where the angle of the extrusion lines determine the type of sheen. [Mark’s] progress is beautifully captured on his twitter feed where he rolls out variations of this style.
Photographs simply don’t do justice to this technique, but you need not be left unsatisfied. Mark has left us with a thorough introduction to creating these patterns on your own printer in the video after the break.
3D Printers have been in the hands of hackers for well over ten years, but the dream is far from over and certainly not overslept. This year’s Midwest RepRap Festival is a testament to the still-growing excitement, and world where 3D printing is alive and kicking on the next level.
This past weekend, I took up my friend [Eric’s] advice to come down and participate firsthand, and I was simply blown away. Not only did we witness the largest number of attendees to date, MRRF 2019 spilled into not one but two conference halls at the Goshen Fairgrounds.
We can make our 3D-printed parts even more capable when we start mixing them with some essential “mechanical vitamins.” By combining prints with screws, nuts, fasteners, and pins, we get a rich ecosystem for mechanism-making with capabilities beyond what we could simply print alone.
Today I’d like to share some tips on one of my favorite functional 3D-printing techniques: adding heat-set inserts. As someone who’s been installing them into plastic parts for years manually, I think many guides overlook some process details crucial to getting consistent results.
Make no mistake; there are a handful of insert guides already out there [1, 2]. (In fact, I encourage you to look there first for a good jump-start.) Over the years though, I’ve added my own finishing move (nothing exotic or difficult) which I call the Plate-Press Technique that gives me a major boost in consistency.
Join me below as I fill in the knowledge gaps (and some literal ones too) to send you back to the lab equipped with a technique that will give you perfectly-seated inserts every time.