The Hackaday Prize is in full swing, and that means we’re starting to see all the builds a few select people have been saving up for the past few months. [yowhwui] has been working on a 3D printed electric longboard for a while now, and this build is really solid. He already has over 150km on the odometer, and the 3D printed parts are still holding up.
The power for this motor comes from a 6374 brushless motor running at 192 kV. This, plus two 4S 30C 5000mAh LiPo batteries propel this longboard to speeds up to 42 km/h (2.18 Saxon leagues per quarter hour), all while weighing about 8kg.
Since [yowhwui] is using the motor for power and braking (electric motors are neat), this longboard needs to be designed with belt skipping in mind. To that end, he’s designed a drive system with an idler, and nearly every single part is 3D printed. The first revision of the hardware was printed in PETG. While PETG was more than strong enough, it was also too brittle. This led to a few cracks. After printing the parts out again in ABS, [yowhwui] put a few more kilometers on this longboard, and there are no immediate signs of wear.
Looks like electric longboards are becoming a thing, with increasingly complex electronics going into them to squeeze as much performance as possible out of them. When an electric longboard lasts for 35 miles, can longboard hypermiling be far behind?
If endurance longboarding sounds familiar, it’s because we just covered a 25-mile electric that outlasted its rider. To get the extra 10 miles, [Andrew] cheated a little, with a backpack full of extra batteries powering his modified Boosted Board, a commercially available electric longboard. But the backpack battery was only a prototype, and now [Andrew] is well on his way to moving those batteries to a custom underslung enclosure on his new “Voyager” board. Eschewing balancing and monitoring circuitry in favor of getting as many batteries on board as possible, [Andrew] managed sixty 18650s in a 10S6P configuration for 37 volts at 21 Ah. He didn’t scrimp on tools, though – a commercial terminal welder connects all the battery contacts. We really like the overall fit and finish and the attention to detail; an O-ring seal on the 3D-printed enclosure is a smart choice.
Voyager isn’t quite roadworthy yet, so we hope we’ll get an update and perhaps a video when [Andrew] goes for another record.
What could be better than a holiday ride past the palm trees and blue waters of a Mediterranean resort town? Perhaps making that ride on a long-range electric longboard of your own design will ice that particular cake.
And when we say long range, we mean it – an estimated 25 miles. The only reason [overclocker_kris] couldn’t come up with an exact number in the test drive seen below is that he got too tired to continue after mile 20. With a bit of juice left in the 64-cell battery pack, built from 18650s harvested from old laptops, the board was sure to have another five miles in it. A custom molded underslung carbon fiber enclosure houses the battery pack and electronics, including the receiver for the handheld remote control and the ESCs for the two motors. Motor mounts were fabbed from aluminum and welded to the trucks, with power transmission through timing belts to 3D-printed pulleys. It’s a good-looking build, and topping out at 22 MPH isn’t too shabby either.
[Tallaustin] worked at Stratasys as an intern this past summer. They let him know that he was welcome to use their fancy industrial printers as much as he’d like. Not to waste such an opportunity he promptly got to work and designed an electric longboard, printable for a mere $8,000.
[Tallaustin] is presumably tall, and confided to Reddit that he weighs in at 210 lbs. For those of us who have had the pleasure of designing for FDM 3D printing, we know that getting a skateboard one can actually skate on without it delaminating somewhere unexpected is pretty difficult if you weigh 80 lbs, 200+ is another category entirely. So it’s not surprising that his first version shattered within in moments of testing.
So, he went back to the drawing board. Since he had his pick of all of Stratasys’s most expensive and fine spools of plastic, he picked one of the expensivest and finest, Ultem 1010. Aside from adding a lot of ribbing and plastic, he also gave it a full rundown with some of SolidWorks’s simulation tools to see if there were any obvious weak points.
Six days of exceedingly expensive printing later, he had a working long board. The base holds some batteries, an ESC, and a 2.4 GHz transceiver. The back has a brushless motor that drives a pulley slotted into one of the wheels. The rest is standard skateboard hardware.
If you’d like to build it yourself he’s posted the design on Thingiverse. He was even nice enough to put together a version that’s printable on a plebeian printer, for a hundredth of the price.
Skateboarding is a sport that was born of hacking. The identity of the person who first nailed roller skate wheels to a board with a milk crate box is lost to history. Those crate scooters were a staple of the 1940’s and 1950’s neighborhoods. Everyone built their own scooter, so the designs evolved. Eventually the milk crates disappeared. At some point, surfers realized that they could use these wheeled boards to surf the concrete jungle. Things just took off from there. Skateboarding is now a multi-billion dollar industry, but at its heart there are still hackers trying out new designs. This week’s Hacklet is all about skateboarding projects.
We start with [brian.rundle] and Electric Longboard. [Brian] built his board using trucks and mechanical parts from a DIY skateboard online shop. The motor is a brushless outrunner R/C plane motor from HobbyKing. Batteries are of the LiPo variety. An Arduino Nano provides the PWM signal which drives the Electronic Speed Control (ESC). Throttle control is via RF link using the popular Nordic Semi NRF2401. [Brian] is focusing on building a safe skateboard. He designed it to carry two batteries, though only one is in use at a time. Rather than use a switch, he’s created a fool-proof system with arming plugs and jumpers. Each battery has its own arming plug. There is one jumper, so only one battery can be connected to the board at a time.
Next up is [suiram21] with Longboard Brake. Downhill longboarding can be a dangerous sport. Running downhill at 40MPH or more with no brakes makes for quite an adrenaline rush. [suiram21] loves longboarding but wanted the safety of having a brake if and when he needed it. He started with a Onda board, which is a longboard with large diameter wheels. He 3D printed brackets for a cable actuated braking system. The brake is activated by stepping on a lever at the rear of the board. A lever presses a bicycle brake pad into the inside edge of the tire. This brings the board to a gentle stop. [suiram21] is thinking of adding a second brake to the other wheel to increase braking authority.
Next we have [edbraun] with Skateboard Speedometer by inventED. [edbraun] wanted to know how fast he was going. A GPS would work, but GPS signals are often blocked in cities. A more accurate way to gather speed data is directly from the wheels. Two tiny magnet plugs are placed in holes drilled in the wheel. A hall effect sensor detects the magnets and passes this data on to an Arduino Pro Mini. Once the speed is calculated, it’s sent to a Bluetooth radio. [edbraun’s] Android phone receives the data and displays current speed and total distance traveled. The speedometer and its slick 3D printed case almost hide between the trucks and the board itself. Nice work [edbraun]!
Finally we have Hackaday alum [Josh Marsh] and EV Commuter Longboard. [Josh] uses an electric longboard for his daily commute. His project is an excellent overview and tutorial on building an electric skateboard from scratch. Like many others, [Josh] utilizes R/C Airplane brushless motors and speed controllers. An Arduino or similar microcontroller is all you need to drive these devices. For batteries, [Josh] loves LiPo packs. Long form six cell affairs provide 22.2 Volts with a capacity of 5000 mAh or more. Plenty of power for carving your way to work!
Skateboards are fun, but you have to do all that pesky kicking in order to get anywhere. That’s why [Nick] decided to build his own electric skateboard. Not only is the skateboard powered with an electric motor, but the whole thing can be controlled from a smart phone.
[Nick] started out with a long board deck that he had made years ago. After cleaning it up and re-finishing it, the board was ready for some wheels. [Nick] used a kit he found online that came with the trucks, wheels, and a belt. The trucks have a motor mount welded in place already. [Nick] used a Turnigy SK3 192KV electric motor to drive the wheels. He also used a Turnigy electronic speed controller to make sure he could vary the speed of the board while riding.
Next [Nick] needed some interface between a smart phone and the motor controller. He chose to use an Arduino Nano hooked up to a Bluetooth module. The Nano was able to directly drive the motor controller, and the Bluetooth module made it easy to sync up to a mobile phone. The Android app was written using MIT’s App Inventor software. It allows for basic control over the motor speed so you can cruise in style. Check out the video below for a slide show and some demonstration clips.
DIY electric longboards are a ton of fun to build and ride (we’ve featured several builds before). Most boards have batteries strapped to the bottom of a rigid board, or they have battery packs near each truck so the board can still flex. Instead of going with either of these designs, [Ben] created a custom battery pack design that’s able to flex with the board.
[Ben]’s pack is made up of A123 26650 cells nestled in his custom-fabricated enclosure. [Ben] designed his pack in CAD and used a CNC machine to create a foam mold. He used the mold to do a fiberglass layup, vacuum-bagged it, and left it to cure. Since the fiberglass bonded really well to the foam, [Ben] used acetone to dissolve the foam while leaving his fiberglass layup intact.
[Ben]’s pack fits 18 cells which he soldered together with some flexible copper grounding wire. The top side of the enclosure is covered with a layer of insulating rubber, and the rim is covered with a soft foam to form a gasket against the board. As you can see, the pack bends really well with the board, and it doesn’t look like [Ben] has had any issues with his design so far. Check out [Ben]’s blog for more info and for more details on the overall design of his board.