HP Rolls Out Metal 3D Printers

September 14, 2018 by Al Williams 36 Comments

You normally think of HP as producing inkjet and laser printers. But they’ve been quietly building 3D printers aimed at commercial customers. Now they are moving out with metal printers called — predictably — the HP Metal Jet. The video (see below) is a little glitzy, but the basic idea is that print bars lay down powder on a 21-micron grid. A binding agent prints on the powder, presumably in a similar way to a conventional inkjet printer. A heat source then evaporates the liquid from the binder.

The process repeats for each layer until you remove the part and then sinter it using a third-party oven-like device. According to HP, their technique has more uniform material properties than fusing the powder on the bed with a laser. They also claim to be much faster than metal injection molding.

Continue reading “HP Rolls Out Metal 3D Printers” →

Awesome Looking 3D Printed RC Plane Is Full Of Design Considerations

September 11, 2018 by Steven Dufresne 18 Comments

Designing and 3D printing RC planes offer several interesting challenges, and so besides being awesome looking and a fast flier, [localfiend’s] Northern Pike build is definitely worth a look. Some details can be found by wading through this forum but there’s also quite a bit on his Thingiverse page.

Tongue-and-groove joint for the wing — Tongue-and-groove joint

Naturally, for an RC plane, weight is an issue. When’s the last time you used 0% infill, as he does for some parts? Those parts also have only one perimeter, making this thin-walled-construction indeed. He’s even cut out circles on the spars inside the wings. For extra strength, a cheap carbon fiber arrow from Walmart serves as a spar in the main wing section. Adding more strength yet, most parts go together with tongue-and-groove assembly, making for a stronger join than there would be otherwise. This slotted join also acts as a spar where it’s done for two wing sections. To handle higher temperatures, he recommends PETG, ABS, ASA, Polycarbonate, and nylon for the motor mount and firewall while the rest of the plane can be printed with PLA.

As you can tell from the videos below, [localfiend’s] flier is a high-performance 3D printed machine. But such machines don’t have to be relegated to the air as this RC jet boat demonstrates. Though some do hover on a thin cushion of air.

Continue reading “Awesome Looking 3D Printed RC Plane Is Full Of Design Considerations” →

No Signal For Your Radio-Controlled Watch? Just Make Your Own Transmitter

September 10, 2018 by Ben James 37 Comments

You can win any argument about the time when you have a radio controlled watch. Or, at least, you can if there’s any signal. [Henner Zeller] lives in a place where there is no reception of the DCF77 signal that his European wristwatch expects to receive. Consequently, he decided to make his own tiny transmitter, which emulates the DCF77 signal and allows the watch to synchronise.

A Raspberry Pi Zero W is the heart of the transmitter, and [Henner] manages to coax it into generating 77500.003Hz on a GPIO pin – close enough to the 77.5kHz carrier that DCF77 uses. The signal is AM, and transmits one bit/s, repeating every minute. A second GPIO performs the required attenuation, and a few loops of wire are sufficient for an antenna which only needs to work over a few inches. The Raspberry Pi syncs with NTP Stratum 1 servers, which gives the system time an accuracy of about ±50ms. The whole thing sits in a slick 3D printed case, which provides a stand for the watch to rest on at night; this means that every morning it’s synchronised and ready to go.

[Henner] also kindly took the time to implement the protocols for WWVB (US), MSF (UK) and JJY (Japan). This might be just as well, given that we recently wrote about the possibility of WWVB being switched off. Be sure to check the rules in your area before giving this a try.

We’ve seen WWVB emulators before, like this ATtiny45 build, but we love that this solution is an easy command line tool which supports many geographical locations.

Hummingbirds, 3D Printing, And Deep Learning

August 31, 2018 by Ben James 15 Comments

Setting camera traps in your garden to see what local wildlife is around is quite popular. But [Chris Lam] has just one subject in mind: the hummingbird. He devised a custom setup to capture the footage he wanted using some neat tech.

To attract the hummingbirds, [Chris] used an off-the-shelf feeder — no need to re-invent the wheel there. To obtain the closeup footage required, a 4K action cam was used. This was attached to the feeder with a 3D-printed mount that [Chris] designed.

When it came to detecting the presence of a hummingbird in the video, there were various approaches that could have been considered. On the hardware side, PIR and ultrasonic distance sensors are popular for projects of this kind, but [Chris] wanted a pure software solution. The commonly used motion detection libraries for this type of project might have fallen over here, since the whole feeder was swinging in the air on a string, so [Chris] opted for machine learning.

A RESNET architecture was used to run a classification on each frame, to determine if the image contained a hummingbird or not. The initial attempt was not greatly successful, but after cropping the image to a smaller area around the feeder, classification accuracy greatly increased. After a bit of FFmpeg magic, the selected snippets were concatenated to make one video containing all the interesting parts; you can see the result in the clip after the break.

It seems that machine learning and wildlife cams are a match made in heaven. We’ve already written about a proof-of-concept project which identifies different animals in the footage when motion is detected.

Continue reading “Hummingbirds, 3D Printing, And Deep Learning” →

3D Printed Magnetic Dust Port Keeps Shop Clean

August 29, 2018 by Tom Nardi 33 Comments

Too often we hear that 3D printing is at best only a way for making prototypes before you invest in “real” manufacturing. At worst, it’s a way to make little toys for your desk or cubicle. The detractors say that 3D printing doesn’t lend itself to building practical devices, and even if you do manage to print something useful, you probably could have made it faster or better with more traditional manufacturing methods. So naturally we’re especially excited when we see a printed design that manages to buck both criticisms at once.

Not only does this magnetic dust port connector created by [Taylor Landry] have a clear practical purpose, but its design largely defies normal construction techniques. It consists of two flanges, sized for common 4″ flexible ducting, which feature embedded magnets on the faces.

This allows the two sides of the coupling to easily be connected and disconnected without relying on threads or a friction fit. Not only would threads likely get caked with sawdust, but the magnetic connection allows the coupling to release in the event somebody trips on the duct or the tool is moved.

Currently only one type of coupling is available, but [Taylor] says he’s looking at adapting the design to other tools. He also mentions that the magnets he’s currently using are a custom size he had left over from a previous project, so if you’re looking to replicate the design you might need to tweak the magnet openings. Luckily, he’s provided the STEP files so you don’t have to hack the STL.

A quick connect dust port like the one [Taylor] has come up with seems like it would be a perfect addition to the whole-shop dust collection systems we’ve covered in the past. In fact, it might not even be the only 3D printed component in the system.

Empty Can Upcycled Into Portable Speaker

August 28, 2018 by Tom Nardi 26 Comments

We aren’t suggesting you go digging through the trash looking for empty cans, but if you’ve already got some empty cans in the privacy of your own home, you could certainly do worse than turning them into unique enclosures for your electronics projects. Better than sitting in the landfill, surely.

This hack from [Robin Hartley] turns an empty Cadbury hot chocolate can into a portable speaker that’s sure to get some attention. But don’t be fooled: a surprisingly amount of engineering went into this project in the form of a 3D printed structure on the inside of the can. Even if you aren’t big on the idea of putting your next project into a piece of literal trash, there’s something to be said for how professionally everything fits together in this build.

The key to this build is the 3D printed “skeleton” that holds the speaker and circuit board in place. An especially nice touch is how [Robin] designed the mount for the speaker: as it had no flange to attach to, he made a two piece clamp that screws together around the rear of the speaker and holds it in place.

You may wonder why somebody who’s clearly as well versed in CAD and 3D printing as [Robin] is might want to use an empty can as an enclosure; surely he could just design and print a case? Undoubtedly. But the goal here is to reuse what would otherwise be trash, and that occasionally means taking the “scenic” route as it were.

To take this concept to the next level, check out the upcycled speaker box we recently covered. We’ve seen some gorgeous home audio builds that started as a curbside find, but depending on how lucky you are, it’s almost like cheating.

Continue reading “Empty Can Upcycled Into Portable Speaker” →

Self Folding Origami From A 3D Printer

August 27, 2018 by Al Williams 12 Comments

If you’ve done much 3D printing, you probably curse how plastic warps as it cools down and heats. There’s nothing more upsetting than watching a six hour print start curling off the bed and starting its inexorable march to the trash can. However, researchers at Carnegie Mellon have found a way to harness that tendency to warp with heat to make self-folding structures like those seen in the video below. There’s a paper about how it works available, too.

The Thermorph process uses commercially-available 3D printers, but requires special software. You might wonder why you would want to fold, say, a rose, when you could just print it as a fully-formed 3D model. The paper suggests that printing self-folding structures is faster and can save up to 87% on print times for the right models.

Continue reading “Self Folding Origami From A 3D Printer” →