Thrift Store Razor Scooter Gets More Kick

Beyond pride, the biggest issue keeping adults off small motorized scooters is the fact that their tiny motors usually don’t have the power to move anything heavier than your average eighth grader. That didn’t stop [The_Didlyest] from snapping up this $7 thrift store find, but it did mean the hot pink scooter would need to be beefed up if it had any hope of moving 170 lbs of hacker.

Logically, the first step was fitting a more capable motor. [The_Didlyest] used an electric wheelchair motor which had a similar enough diameter that mounting it was fairly straightforward. The original sprocket and chain are still used, as are the mounting holes in the frame (though they had to be tapped to a larger size). That said, the new motor is considerably longer than its predecessor so some frame metal had to be cut away. This left the scooter without a kickstand and with a few inches of motor hanging out of its left side, but it’s all in the name of progress.

Naturally the upgraded motor needed similarly upgraded batteries to power it, so [The_Didlyest] put together a custom pack using eighteen 18650 cells spot welded together for a total output of 25V. Coupled with a 60A battery management system (BMS), the final 6S 3P configured pack is a very professional little unit, though the liberal application of duct tape keeps it from getting too full of itself.

Unfortunately the original motor controller consisted of nothing but relays, and didn’t allow adjusting speed. So that needed to go as well. In its place is a homebrew speed controller made with three parallel MOSFETs and an Arduino to read the analog value from the throttle and convert that into a PWM signal.

[The_Didlyest] says the rear tire is now in need of an upgrade to transmit all this new power to the road, and some gearing might be in order, but otherwise the scooter rebuild was a complete success. Capable of mastering hills and with a top speed of about 10 MPH, the performance is certainly better than the stock hardware.

Of course this is far from the first time we’ve seen somebody put a little extra pepper on a scooter. Some of them even end up being street-legal rides.

Scooter Hauls Kids With A Little Heavy Metal

Where there’s a will, there’s a way. Similarly, where there’s a paying customer and a well stocked metalworking shop, there will also be a way. That’s about all the backstory you need to understand this latest creation from [Richard Day] of 42Fab. A customer asked him to build something that didn’t exist, and in a few hours he not only fabricated it from scratch but documented the whole thing for our viewing pleasure.

The object in question is a mount that would allow the customer to pull a “Burley Bee” kid trailer behind their electric scooter. The trailer is only meant for a bicycle, but the expected stresses of getting pulled around by a scooter seemed similar enough that [Richard] figured it should work. Especially since the ride height of the scooter lined up almost perfectly with the trailer’s tongue. The trick is, he wanted to avoid making permanent changes to either the scooter or the trailer.

On the scooter side, [Richard] came up with a clamp arrangement that would squeeze onto the frame. This gave him plenty of strength, without having to put any holes in the scooter. To create the clamp he took two pieces of 1/4″ x 2″ steel flat bar and welded 5/16″ nuts to them. By drilling the threads out of outer nuts they act as bushings, so cranking down on the bolts draws the two pieces together. To simplify the alignment, he welded the nuts to the bars while the bolts were threaded in, so he knew everything would be in place.

For the trailer side, he took another piece of flat steel and turned it into a “U” shape by cutting almost all the way through the back of it and then folding it over in his vice. A bead of metal was then laid in the cut with the welder to strengthen it back up. [Richard] used this opportunity to demonstrate the difference between pushing and pulling the torch while welding, which is an interesting tip to file away. A hole drilled through the two sides and a little grinding, and it’s ready to mount.

Between the two fabricated components is some flat stock welded at an eyed up angle. As [Richard] says in the video, the nice thing about these one-off projects is that you can basically design on the fly. Plus you can always use a hammer to make some final adjustments.

While his isn’t the first bike trailer hack we’ve seen here at Hackaday, it would be fair to say it’s something of a rarity around these parts. Usually we get word of somewhat larger bits of kit getting dragged around.

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Electric Chainsaw Teardown

An electric chainsaw with its case removed

For his Beyond Unboxing series, [Charles] tore apart a Ryobi cordless chainsaw to get a better look at how this battery powered tool works.

Inside he found a three-phase motor and controller. This motor looks like it could be useful in other projects since it has a standard shaft. The battery pack was popped open to reveal a set of LG Chem 21865 cells, and some management hardware.

With all the parts liberated from the original enclosure, [Charles] set up the motor, controller, and battery on the bench. With a scope connected, some characterization of the motor could be done. A load was applied by grabbing the spinning shaft with welding gloves. [Charles] admits that this isn’t the safest way to test a motor.

While it is a very fast motor, the cut-in speed was found to be rather low. That means it can’t start a vehicle from a stop, but could be useful on e-bikes or scooters which are push started.

This chainsaw a $200 motor, controller, and battery set that could be the basis of a DIY scooter. It sounds great too, as the video after the break demonstrates.

[Thanks to Dane for the tip!]

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3kW Electric Scooter

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[Exco] had been playing around with the idea of building an electric scooter for a while now, and over the holidays he decided to just do it.

Similar to the motorized long board we shared last month, this scooter makes use of an RC hobby motor — in this case, a 63mm 3kW brushless outrunner (for a RC plane), coupled with a 100A ESC. He bought the scooter (“kick board”) off eBay for cheap, and spent a few days in the machine shop modifying it. It has better wheels now, and custom milled aluminum brackets for mounting the motor. The drive system uses a belt and pulley with a sliding rail to provide tensioning.

To power it, he bought a bunch of 2.5Ah, 18V LiPo packs on eBay originally from a Makita drill set. He then sorted out the cells, removed the dead ones, and soldered everything together for his own Frankenstein pack to balance them. The final configuration features twenty-one 18650 lithium cells. He even shrink wrapped it, which makes it look relatively professional!

It’s controlled by a push-button potentiometer hooked up to the ESC. Theoretical top speed is about 27km/h @ 1285RPM, and they managed to get it up to 25km/h in a real test. There’s more info over at the Endless Sphere forum, and we’ve got two test videos for you after the break.

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Electric Snow Scooter

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[Dane] decided he wanted to make a rather large electric scooter, capable of taking him through even the most inclement weather — that’s right, even snow.

Well, after about 18 months of stop and go work it is finally complete — for now. It features an impressive 7kW brushless 3-phase motor, a massive lithium ion battery pack and more custom parts then you could shake a stick at!

The frame started out as one of those big push scooters from the 80’s, in fact, it is the same as the one shown in Macklemore’s Thrift Shop video (pic)! But since then it has had many a modification done to it — it looks as though the front end is the only part that wasn’t touched!

He’s got an incredible build log  his website, so if you want to build your own (you will once you’ve seen the video after the break), it’s a great starting point.

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Self balancing unicycle built from old scooter

[Glenn] had an old electric scooter/motorcycle in his garage that had long ago given up the ghost. Without a working battery and motor controller this scooter wasn’t beyond repair, but [Glenn] thought he could use it to build something much, much cooler. What he came up with is a self-balancing unicycle that borrows inspiration from a Segway and other self-balancing robots.

After cutting the drive chain off his scooter, [Glenn] began work on installing a new motor controller and battery. To make this unicycle balance itself, he would need a few gyroscopes and accelerometers provided via an Arduino and Sparkfun IMU shield.

After tuning his PID loop, [Glenn] hopped on his new ride and took it for a spin with the help of a pair of ski poles. It’s much easier to ride than a traditional unicycle and [Glenn] says he’s getting better at riding it.

A123 LiIon battery pseudo extra


Every so often I have to slap myself in the head. I’m surprised that we haven’t covered these things by now. DeWalt’s been selling a LiIon 36 volt battery pack that’s full of the latest A123 cells. These are the same ones that were used in the Killacycle. (I think they’ve got a new batch of cells now).

A while back, [Jeff] sent in a circuit for using multiple packs, leaving the internal BMS in place. [The link is fixed now]

[Robert] sent in a scooter that’s been designed to run these same cells. The custom fabrication and machine work looks fantastic.