Benchmarking a Garbage Disposal Using The 3DBenchy Tugboat

We’ve always had a love-hate relationship with 3DBenchy, the tugboat-shaped 3D printer calibration target. On one hand, it’s incredibly useful to have a common, widely used, and challenging benchmark object to evaluate printer performance and improve tuning, but we’d somehow like to get back the countless frustrated hours we’ve spent trying to get the damn thing perfect with various printers. So, it was with no little joy that we watched the video below by [Eric R Mockler], in which he uses 3DBenchy prints to benchmark his newest acquisition: a new-in-box garbage disposal he scored off Craigslist. Take that, tugboat!

[Eric] is considering using the disposal as the first step in a failed-print-recycling method to ultimately turn the waste back into filament, presumably to print more tugboats. The tiny bits produced by the disposal should provide a reasonable substitute for pelleted plastic feedstock going into a filament extruder, if the disposal is up to the task, that is. Reasoning that any device capable of grinding chicken bones should handle little plastic tugboats just as well, [Eric] gave it shot, and found that the ⅓-horsepower disposal had no problem grinding even 100%-infill PLA prints.

The video is short and to-the-point, so we’ll even excuse the portrait orientation, just this once. If you’re considering recycling your failed prints, too, you’ll also need a filament extruder, and we’ve got you covered with a low-cost version, or a high-throughput one.

Continue reading “Benchmarking a Garbage Disposal Using The 3DBenchy Tugboat”

Laser Draws Weather Report

Have you ever wished that a laser could tell you the weather? If you have, then [tuckershannon] has you covered. He’s created a machine that uses a laser and some UV sensitive paper to draw the temperature and a weather icon! And that’s not all! It’s connected to the internet, so it can also show the time and print out messages.

Building on [tuckershannon]’s previous work with glow-in-the-dark drawing, the brains inside this machine is a Raspberry Pi Zero. The laser itself is a 5mw, 405nm laser pointer with the button zip-tied down. Two 28BYJ-48 stepper motors are used to orient the laser, one for the rotation and another for the height angle. Each stepper motor is connected to a motor driver board and then wired directly to the Pi.

The base and arm that holds the laser were designed in SolidWorks and then 3d printed. The stepper motors are mounted perpendicular to one another and then the laser pointer mounted at the end. The batteries have been removed from the laser and the terminals are also wired directly to the raspberry pi. The Pi is then connected to Alexa via IFTTT so that it can be controlled by voice from anywhere.

The real beauty of [tucker]’s laser drawing machine is that is will draw out the temperature and weather icon, as well as drawing the time in either digital or analog forms! We’ve seen [tuckershannon]’s work before. The precursors to this project were his clock which uses a robotic arm with a UV LED on it to draw the time and another clock which uses similar robotic arm only with a laser attached. Let’s hope we get to see the rest of [tucker]’s progress!

Continue reading “Laser Draws Weather Report”

Budget Dehydrator Gives your Damp Filament a Second Chance

If you’ve had the misfortune of leaving your 3D printer filament out on a muggy day or, heaven forbid: showering with it, it’s probably soaked up quite a bit of moisture. Moisture will do more than just make your printer sound like Rice Crispies, it’ll ruin surface finishes and cause the filament to string into thin wisps between separate geometries on the same layer. Luckily for us, though, both [SafetyGlassesRequired] and [Joe Mike Terranella] give us the breakdown on taking a pair of snippers and about $40 in cash to start drying out our filament far away from the possibility of ruining any nearby kitchen ovens.

If you’ve been circling the 3D printer community for a while, you might have already heard about this trick. But with the arrival of a curiously-culinary-looking contraption called PrintDry, we can’t let the elephant in the room keep silent for much longer. Rather than risk our own pennies and leave ourselves stranded with a device that only makes the jerky on the box cover, [SafetlyGlassesRequired] and [Joe Mike Terranella] kindly prove our suspicions for us once and for all: a food dehydrator works perfectly for drying all that filament that we left out in the rain!

Clumsiness aside, a dehydrator isn’t a bad investment in the long run. Not only can we keep our supply dry, we might just be able to give all that freebie filament (that we dug out of the trash) a second life by resetting it to a clean, dry state.

These dehyrdators will toast all that moisture out of your filament, but it wont keep them dry whilst printing. For that problem, you’ll need to summon a heated drybox like this one.

[Joe Mike’s] solution will run us about $40. If you can do better, let us know in the comments.

Continue reading “Budget Dehydrator Gives your Damp Filament a Second Chance”

3D Printed Airplane Engine Runs on Air

One of the most important considerations when flying remote-controlled airplanes is weight. Especially if the airplane has a motor, this has a huge potential impact on weight. For this reason, [gzumwalt] embarked on his own self-imposed challenge to build an engine with the smallest weight and the lowest parts count possible, and came away with a 25-gram, 8-part engine.

The engine is based around a single piston and runs on compressed air. The reduced parts count is a result of using the propeller axle as a key component in the engine itself. There are flat surfaces on the engine end of the axle which allow it to act as a valve and control its own timing. [gzumwalt] notes that this particular engine was more of a thought experiment and might not actually produce enough thrust to run an airplane, but that it certainly will spark up some conversations among RC enthusiasts.

The build is also one of the first designs in what [gzumwalt] hopes will be a series of ever-improving engine designs. Perhaps he should join forces with this other air-powered design that we’ve just recently featured. Who else is working on air-powered planes? Who knew that this was a thing?

Continue reading “3D Printed Airplane Engine Runs on Air”

3D Prints That Fold Themselves

3D printing technologies have come a long way, not only in terms of machine construction and affordability but also in the availability of the diverse range of different printing materials at our disposal. The common consumer might already be familiar with the usual PLA, ABS but there are other more exotic offerings such as PVA based dissolvable filaments and even carbon fiber and wood infused materials. Researchers at MIT allude to yet another possibility in a paper titled “3D-Printed Self-Folding Electronics” also dubbed the “Peel and Go” material.

The crux of the publication is the ability to print structures that are ultimately intended to be intricately folded, in a more convenient planar arrangement. As the material is taken off the build platform it immediately starts to morph into the intended shape. The key to this behavior is the use of a special polymer as a filler for joint-like structures, made out of more traditional but flexible filament. This special polymer, rather atypically, expands after printing serving almost like a muscle to contort the printed joint.

Existing filaments that can achieve similar results, albeit after some manual post-processing such as immersion in water or exposure to heat are not ideal for electronic circuits. The researchers focus on this new materials potential use in manufacturing electronic circuits and sensors for the ever miniaturizing consumer electronics.

If you want to experiment printing extremely intricate structures, check out how [_primoz_] brilliant technique revolutionized how the 3D printing community prints thin fibers, bristles, and lion sculptures.

Continue reading “3D Prints That Fold Themselves”

Polyurethane, Meet 3D Printing

3D printing makes prototyping wonderful. But what do you do when your plastics of choice just aren’t strong enough? For [Michael Memeteau], the answer was to combine the strength of a vacuum-poured polyurethane part with the ease of 3D-printed molds. The write-up is a fantastic walk through of a particular problem and all of the false steps along the way to a solution.

The prototype is a connected scale for LPG canisters, so the frame would have to support 80 kg and survive an outdoor environment. Lego or MDF lattice were considered and abandoned as options early on. 3D printing at 100% infill might have worked, but because of the frame’s size, it would have to be assembled in pieces and took far too long anyway.

The next approach was to make a mold with the 3D printer and pour the chosen polyurethane resin in, but a simple hollow mold didn’t work because the polyurethane heats as it cures. The combined weight and heat deformed the PLA mold. Worse, their polyurethane of choice was viscous and cured too quickly.

The solution, in the end, was a PET filament that deforms less with heat, clever choice of internal support structures to hold the stress in while being permeable, and finally pouring the polyurethane in a vacuum bag to help it fill and degas. The 3D-printed hull is part of the final product, but the strength comes from the polyurethane.

Mold-making is one of the killer apps of 3D printing. We’ve seen 3D prints used as molds for spin-casting hollow parts, and used as a sacrificial shell for otherwise epoxy parts. But for really complex shapes, strength, and ease of fabrication, we have to say that [Michael]’s approach looks promising.

3D Printing T-Shirt Designs

Usually, t-shirt designs are screen printed, but that’s so old school. You have to make the silkscreen and then rub paint all over – it’s clearly a technique meant for the past. Well, fear not, as [RCLifeOn] is here to bring us to the future with 3D Printed T-Shirt Designs.

[RCLifeOn] affixes t-shirts to his print build platform and boom: you’ve got 3D printed graphics. He started by using PLA which, while it looked great, wasn’t up to a tussle with a washing machine. However, he quickly moved on to NinjaFlex which fended much better in a wash cycle. While the NinjaFlex washed better, [RCLifeOn] did have some issues getting the NinjaFlex to adhere to the t-shirt. With a little persistence and some settings tweaking, he was able to come out ahead with a durable and aesthetically pleasing result.

Now, 3D printing isn’t going to replace screen printing, but it’s also not going to replace injection molding. What 3D printing lacks in speed and efficiency, it makes up in setup time & cost. In other words, if you need 50 t-shirts of the same design, screen printing is the way to go. But, if you need 50 shirts, each with a different design, you just might want to follow in [RCLifeOn’s] footsteps.

Anyways, we don’t have much on 3D printing t-shirts, but we do have other useful information on 3D printing slinkys and 3D printing project enclosures. And, if you’d rather do it the old-school way, we can show you how to silkscreen all the things.