This year I pulled This Old Tony‘s name for Makers Secret Santa. I was inspired by Tony’s love of benders and bending, and built him a toy from my childhood in the shape of a letter T. It’s got a magnetic spinning device that rides along the wire, and these little bends provide a turnaround point so you can, with practice, get the spinner to move continuously along the track.
Supplies from Digi-Key, this project’s sponsor:
- Seeed Xiao RP2040 microcontroller
- Adafruit lipoly backpack charging board
- Small lipoly battery
- Tiny Neopixel strip
- 30g stranded wire in three different colors
- 3D printer filament
- Wire strippers
- Flush cutters
- Soldering iron and solder
This toy was first introduced as Whee-Lo the Magnetic Walking Wheel in 1953, and remained popular for some decades. I remember enjoying it in the early 90s– like a yo-yo, it was fun to see how long you could keep it going. And like a fidget spinner, there’s some satisfaction in the manipulation of gyroscopic force. To make my own, I’d need to bend a bunch of shapes out of wire, and those shapes would have to be aligned quite accurately to provide a consistent track for the wheel.
To achieve such repeatable precision, I’m using the D.I.Wire Pro machine from Pensa Labs, which is a benchtop CNC wire former. I’m using 1/8th inch galvanized steel wire. These machines are configured and shipped with custom tooling for your needs, so if you’re interested in picking up your own D.I.Wire Pro machine, mention my discount code BECKY10 when you reach out to sales. Thanks so much to Pensa Labs for loaning me the machine and making this project possible.
I created my shape in Adobe Illustrator and exported it as three different SVGs. See, my design requires bends in two different planes, so I need to rotate the workpiece 90 degrees between the sections. After some training and experimenting, I got the hang of cranking out a whole bunch of the three-part pieces needed to create my design.
For connecting the pieces at the bottom, I whipped up a quick handle in Tinkercad. It’s got grooves at the corners for the wires to sit in, and a second piece to cover the epoxy joints and wire ends.
While the glue was drying, I got to work on the electronics inside the wheel. At first, I tried 3D printing the wheel as well, but my initial test showed that the magnetic core would need a bit more thought than I had time for on my deadline. See, these heavy magnets make up the axle of the wheel, but these bits on the end aren’t magnets, they are just magnetized by proximity. And this injection molded bit fits all these parts perfectly, so I opted to remove the electronics from the existing plastic wheel and replace them with my own.
The circuit isn’t overly complex when you look at the diagram. Still, this build is exceptionally tiny, so the soldering is tricky and the positioning of everything matters a lot more, as does the gauge and length of the wires.
I made a few wheels and experimented with different positioning of the LED strip. I settled on ringing the core with a strip on each side, which lit up the wheel more completely than the radial positioning I had tried at first. My NeoPixel animation Arduino code can be downloaded here:
I also made Tony one of my waxed canvas tool rolls, which was the subject of another one of my builds this year.
You may be interested in some of my other work:
- Hot Dog Robot for Colin Furze (makers secret santa 2021)
- LED Cylon Scooter – 80s Larson Scanner
- NeoPixel Tiara for Birthday or Prom
- Unicorn Horn with 3D Printing & NeoPixel LEDs