Advances in filaments for FDM 3D printers have come in leaps and bounds over the past few years, and carbon fibre (CF) reinforced filament is becoming a common sight. Robotics extraordinaire [James Bruton] got his hands on some CF reinforced PLA, and ended up building a completely over-engineered 3D printed skateboard. (Video, embedded below.)
[James] started by printing some test pieces with a 0.5 mm and a big 1.2 mm nozzle with and without the CF, which he subjected to cantilever deflection tests. The piece with CF was 20% stiffer than without.
[James] then built an extremely strong and cool looking skateboard deck with alternating section of the CF PLA and toughened PLA, totalling 2.7 kg of filament. It was extremely strong, so after bolting on a set of trucks and wheels, he did some mild riding at a local skate park, where it survived without any problems. He admits it was completely over-engineered, but points out in that the internal cavities in the deck is the perfect place for batteries on an electric long board.
Designing something from the ground up with the strength and weaknesses 3D printing in mind, leads to some very interesting and innovative designs, of which this is a perfect example, and we hope to see many more like it. We’ve featured a number of [James]’ project, including the remote controlled bowling ball he built for [Mark Rober] and his impressive OpenDog and Start Wars robots.
Getting good results from a 3D printer is like Goldilocks’ porridge. There are a lot of things that have to be just right. One common thing that gives people poor results is damp filament. This is especially insidious because the printer will work fine and then after some period time results degrade but it is no fault of the printer mechanics or electronics. There are many ways to attempt to dry filament, but [HydeTheJekyll] prefers using a slow cooker modified to operate with low air pressure.
We assume this works because the low pressure reduces the boiling point of water, allowing the water to boil off at temperatures that won’t distort the filament. The modifications aren’t very severe. You’ll need some hose and a pump along with some silicone caulk and petroleum jelly.
Have you ever thought that Nixie tubes are cool but too hard to control with modern electronics? And that they’re just too expensive? [david.reid] apparently thought so and decided to create his own version of a Nixie tube, and it doesn’t get much cheaper than this.
While working on a 3D printed locomotive with his son, [david.reid] used clear PETG (Polyethylene Terephthalate Glycol) 3D printer filament to move light from LEDs to various parts of the locomotive. He found this was a success, but roughed up the outside of the filament to see what would happen. Lo and behold, a warm glow appeared on the surface of the tube! Like any good hacker, his next thought was of Nixie tubes, as you have seeninmanyclocks.
His basic idea is that with a little heat you can bend the filament into any shape that you like ([david.reid] uses custom molds). You then use some sandpaper to roughen up the outside wherever you’d like light to show, and add an LED at the bottom to light it up!
[Alec Richter] had a good idea on how he could convert the leftover filament spindles from his 3D printer into multi-compartment storage. An empty spindle is fitted with several trays that rotate out from the circle for easy access. With multiple spools rotating on a central axle, you can really see how a bunch of parts could be organized in a column, though not being able to see through the sides probably limits its use somewhat — most of the modular component storage we’ve seen has clear trays.
He has designed drawer bases with removable compartment trays, along with alignment jigs to help you get the drawer installed perfectly the first time. You can download the designs (14 files!) but you need to sign up for an account first. Also, [Alex]s designs fit very specific spindles so be sure of your measurements, etc.
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.
Keeping track of your 3D-printer filament use can be both eye-opening and depressing. Knowing exactly how much material goes into a project can help you make build-versus-buy decisions, but it can also prove gut-wrenching when you see how much you just spent on that failed print. Stock filament counters aren’t always very accurate, but you can roll your own filament counter from an old mouse.
[Bin Sun]’s build is based around an old ball-type PS/2 mouse, the kind with the nice optical encoders. Mice of this vintage are getting harder to come by these days, but chances are you’ve got one lying around in a junk bin or can scrounge one up from a thrift store. Stripped down to its guts and held in place by a 3D-printed bracket, the roller that used to sense ball rotation bears on the filament on its way to the extruder. An Arduino keeps track of the pulses and totalizes the amount of filament used; the counter handily subtracts from the totals when the filament is retracted.
Simple, useful, and cheap — the very definition of a hack. And even if you don’t have a 3D-printer to keep track of, harvesting encoders from old mice is a nice trick to file away for a rainy day. Or you might prefer to just build your own encoders for your next project.
If you’re a heavy user of a 3D printer, or a welder, you’ll know the problem of empty spools. You’ve used up all the filament or the welding wire, and you’re left with a substantial plastic spool. It’s got to be useful for something, you think, and thus it’s Too Good To Throw Away. Before you know it you have a huge pile of the things all looking for a use that you know one day you’ll find.
If you follow the example of [Chuck Hellebuyck], you could use them as wheels for a small go-kart (YouTube link). He 3D-printed some hub adapters for the spools to use skate bearings, mounted them of threaded axles to a classic wooden go-kart frame, and set off downhill wearing his stock-car racing helmet.
Of course, [Chuck]’s go-kart is a bit of fun, but it’s probably fair to say that 3D printer spools are not the ideal wheel. Those rims aren’t particularly durable, and with no tires he’s in for a bumpy ride. Perhaps a tire could be found to fit and a tube placed within it, but that would start to sound expensive against those cheap off-the-shelf wheelbarrow items.
But the project does raise the interesting question: what exactly do you do with your empty spools? There have to be some awesome uses for them, so please share yours in the comments. Meanwhile follow Chuck’s go-kart adventures in the video below the break.