3D Printed RC Jet Boat Gets Up To Speed

September 5, 2018 by Tom Nardi 9 Comments

In one of those weird twists of fate, there’s currently a very high chance that anyone who owns a 3D printer has made a boat with it. In fact, they’ve probably printed several of them, so many that they might even have a shelf filled with little boats in different colors and sizes. That’s because it’s a popular benchmark to make sure the printer is well calibrated. But if you’re going to spend hours printing out a boat, why not print one that’s got some punch?

This 3D printable jet boat designed by [Jotham B] probably isn’t a great print to check your desktop machine’s calibration on, in fact you’re going to want to make sure you’ve got everything dialed in before taking on this challenge. If the classic “Benchy” is the beginners boat, then this is certainly for the 3D printing veterans. But if you’ve got the skills to pull it off, and some RC gear laying around to outfit it with, this could be a great project to end your summer on.

Unless you’ve got an exceptionally tall printer, the 460mm long hull will need to be printed in several pieces and then grafted back together. You could potentially use glue, but something a bit more robust like welding the parts together with a soldering iron is a better bet to make sure your printed boat doesn’t do its best Titanic reenactment out on the lake.

[Jotham] recommends printing the impeller at 0.15mm layer height, as you’ll want all the detail you can muster to provide a smooth surface. You’ll also need to use supports, so expect to spend a fair bit of time cleaning it up post-print. The rest of the model can be printed at 0.3mm, which is going to save a lot of time on the hull. All told, it will take about half a roll of filament to print all the parts for the boat (assuming no mistakes), which puts the pre-electronics cost at around $10 USD.

Speaking of electronics, you’ll need a RC receiver, a servo for steering, an electronic speed controller (ESC), and a suitable motor. [Jotham] used a 3674 brushless motor with a 120A water-cooled ESC, but notes that the setup is way overpowered. In the video after the break you can see the boat spends as much time airborne as it does in the water, which might look cool, but isn’t exactly efficient.

If you want to round out your 3D PLA fleet, we’ve also seen a printed FPV lifeboat as well as a hydrofoil that “flies” through the water.

[Thanks to Aidan for the tip.]

Continue reading “3D Printed RC Jet Boat Gets Up To Speed” →

A Servo Powered Robotic Arm, But Like You’ve Never Seen Before

September 4, 2018 by Ben James 26 Comments

We’ve written about a lot of DIY robotic arms. Some of them are high-performance, some are inexpensive, and some are just uniquely fun. This one certainly falls into the last category; whilst watching an episode of Black Mirror, [Gear Down For What] was struck by inspiration for a thin robotic limb. After some iterations he has a final prototype, and it’s quite something to see in action.

To make a robotic arm as slender as possible, the actuators can’t be mounted on the arm itself but must instead drive the arm remotely. There are a number of ways of doing this, and though [Gear Down For What] considered using pneumatics or hydraulics, he opted to keep it simple with RC servos which produced a nifty solution that we really like.

The arm is made out of a series of 3D printed ball joints, allowing rotation in any direction. The tricky bit is transferring the force from the servos to each joint. Initially bare fishing line was considered, but this made the remote joints difficult to control when lower joints were moving. The solution was to use the fishing line inside of tubing, similar to the way that bike brakes operate. This allows the force to be carried to the appropriate joint regardless of lower movement. Each joint needs an x and y tension to allow it to rotate in any direction, which means an army of sixteen servos is needed to operate the eight segment arm.

Robotic arms are always fun to build and we’ve seen some pretty neat uses for them, such as mapping magnetic fields in 3D, or teaching sign language.

Continue reading “A Servo Powered Robotic Arm, But Like You’ve Never Seen Before” →

Chemistry And Lasers Turn Any Plastic Surface Into A PCB

September 4, 2018 by Dan Maloney 30 Comments

On the face of it, PCB production seems to pretty much have been reduced to practice. Hobbyists have been etching their own boards forever, and the custom PCB fabrication market is rich with vendors whose capabilities span the gamut from dead simple one-side through-hole boards to the finest pitch multilayer SMD boards imaginable.

So why on Earth would we need yet another way to make PCBs? Because as [Ben Krasnow] points out, the ability to turn almost any plastic surface into a PCB can be really handy, and is not necessarily something the fab houses handle right now. The video below shows how [Ben] came up with his method, which went down a non-obvious path that was part chemistry experiment, part materials science. The basic idea is to use electroless copper plating, a method of depositing copper onto a substrate without using electrolysis.

This allows non-conductive substrates — [Ben] used small parts printed with a Formlabs SLA printer — to be plated with enough copper to form solderable traces. The chemistry involved in this is not trivial; there are catalysts and surfactants and saturated solutions of copper sulfate to manage. And even once he dialed that in, he had to figure out how to make traces and vias with a laser cutter. It was eventually successful, but it took a lot of work. Check out the video below to see how he got there, and where he plans to go next.

You’ve got to hand it to [Ben]; when he decides to explore something, he goes all in. We appreciate his dedication, whether he’s using candles to explore magnetohydrodynamics or making plasma with a high-speed jet of water.

Continue reading “Chemistry And Lasers Turn Any Plastic Surface Into A PCB” →

Printed It: Logitech C270 Conversion

September 4, 2018 by Tom Nardi 14 Comments

One of the most practical applications for a home 3D printer is the ability to produce replacement parts; why wait a week for somebody to ship you a little plastic widget when you’ve got a machine that can manufacture a facsimile of it in a couple of hours? But what if your skills and passion for the smell of melting PLA push you even farther? You might move on from printing replacement parts to designing and building whole new devices and assemblies. Arguably this could be considered “peak” 3D printing: using a printer to create new devices which would otherwise be difficult or impractical for an individual to manufacture by more traditional means.

A perfect example is this fantastic total conversion for the Logitech C270 webcam designed by [Luc Eeckelaert]. Officially he calls it a “tripod”, and perhaps that’s how the design started, but the final product is clearly much more than that. It puts the normally monitor-mounted Logitech camera onto an articulated arm, greatly improving the device’s usability. The conversion even includes the ability to manually adjust the focus, a feature the original hardware doesn’t have. It turns the affordable and widely available Logitech C270 into an excellent camera to have on the workbench for documenting projects, or pointing at the bed of your 3D printer.

Continue reading “Printed It: Logitech C270 Conversion” →

Scratch-Built 3D-Printer Goes Back To The Roots Of The Hobby

September 2, 2018 by Dan Maloney 19 Comments

It’s so easy and so cheap to order things like CNC routers and 3D-printers off the shelf that we can be forgiven for forgetting what was once involved in owning machines such as these. It used to be that you had no choice but to build your machine from the ground up. While that’s less true today, it’s still the case if you want to push the limits of what’s commercially available, and this huge scratch-built 3D-printer is a good example of that.

It’s not exactly a fresh build – [Thomas Workshop] posted this last year – but it escaped our notice at the time, and we think the three-part video series below that details the build deserves a look over. When we say scratch built, we mean it. This machine started off as a bundle of aluminum and steel stock. No 80/20 extrusions, no off-the-shelf linear rails – just metal and a plan. The build was helped considerably by a small CNC router, which also had that DIY look, but most of the parts were cut and finished with simple hand tools. The resulting gantry allows an enormous work volume 40 cm in each dimension, with a heated bed that uses four heat mats. We were impressed that [Thomas] got the build just far enough to print parts that were used to finish the build – that’s the hacker spirit.

It’s perhaps not the biggest 3D-printer we’ve seen – that distinction might go to this enormous 8-cubic foot machine – and it certainly can’t print a house. But it’s an impressive build that probably cost a whole lot less than a commercial machine of similar capacity, and it’s got that scratch-built cred.

Continue reading “Scratch-Built 3D-Printer Goes Back To The Roots Of The Hobby” →

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” →

Laser Arm Cannon Scares More Than Metroids

August 30, 2018 by Tom Nardi 5 Comments

There’s an interesting side effect of creating a popular piece of science fiction: if you wait long enough, say 30 or 40 years, there’s a good chance that somebody will manage to knock that pesky “fiction” bit off the end. That’s how we got flip phones that looked like the communicators from Star Trek, and rockets that come in for a landing on a tail of flame. Admittedly it’s a trick that doesn’t always work, but we’re not in the business of betting against sufficiently obsessed nerds either.

Coming in right on schedule 32 years after the release of Metroid on the Nintendo Entertainment System, we now have a functional laser arm cannon as used by the game’s protagonist Samus Aran, courtesy of [Hyper_Ion]. It’s not quite as capable as its video game counterpart, but if your particular corner of the solar system is under assault from black balloons you should be in good shape. Incidentally no word yet on a DIY Power Suit that folds the wearer up into a tiny ball, but no rush on that one.

Modeled after the version of the weapon Samus carried in 2002’s iconic Metroid Prime, [Hyper_Ion] 3D printed the cannon in a number of pieces that screw together in order to achieve the impressive final dimensions. He printed it at 0.3 mm layers to speed up the process, but as you can probably imagine, printing life-size designs like this is not for the faint of heart or short of time. While the use of printed threads does make the design a bit more complex, the fact that the cannon isn’t glued together and can be broken down for maintenance or storage is a huge advantage.

Ever popular NeoPixel strips give the cannon a bit of flash, and a speaker driven by a 2N2222 transistor on an Arduino Nano’s digital pin allows for some rudimentary sound effects with nothing more than a PWM signal. In the video after the break you can see how the lights and sounds serve as a warning system for the laser itself, as the cannon can be seen “charging up” for a few seconds before emitting a beam.

Of course, this is the part of the project that might have some readers recoiling in horror. To provide some real-world punch, [Hyper_Ion] has equipped his arm cannon with a 2.5W 450nm laser module intended for desktop engraving machines. To say this thing is dangerous is probably an understatement, so we wouldn’t blame you if you decided to leave the laser module off your own version. But it certainly looks cool, and as long as you’ve got some proper eye protection there’s (probably) more dangerous things you can do in the privacy of your own home.

Shame this kind of technology wasn’t really practical back when [Ryan Fitzpatrick] made this fantastic Power Suit helmet for a Metroid fan production.

Continue reading “Laser Arm Cannon Scares More Than Metroids” →