There have been so many awesome marble machines this year. So I thought for my last project of 2024, I would build one of my own. Following my own holiday tradition, I wanted to incorporate it into a small Christmas ornament. Check out the video!

Supplies

Parts

298:1 Pololu Metal Geared Motor - https://www.pololu.com/product/994
M2 x 6mm Plastic Threading Screws (Flat)
M2 x 8mm Plastic Threading Screws (Flat)
M1.6 x 3mm Flat Machine Screws (For Pololu Motor Mounting)
10 x 1/8" x 1/8" Neodymium Magnets
4" Fillable DIY Plastic Ball Ornament by Make Market® - https://canada.michaels.com/product/4-fillable-diy-plastic-ball-ornament-by-make-market-10756491
PLA Print Filament
~ 4mm steel balls (I took mine out of a 608 bearing)
USB Battery
Thin Wires

Tools

3D printers
Soldering Iron
Screw Drivers Etc.
Tiny Drill Bit and Drill (for drilling holes for M2 plastic threading screws)

Step 1: 3D Print All of the Files!

Go to https://makerworld.com/en/models/908637#profileId-869076 and download the files to build your christmas ornament. The spiral can be a little tricky, refer to the info on the makerworld link.

Step 2: Solder Long Tiny Wires to the Motor

You're going to need to power the motor somehow. I ultimately used a USB plug for mine, but there are lots of ways you can do it. Even just connect it directly to a battery pack. NOTE: You want the motor to spin counter clockwise.

Step 3: Drill Some Holes

In the plastic Christmas ornament sphere, you will need to drill two holes. One of the holes will be to hold the "Main Body" of the print. The other will be for where the motor wires need to come out. Take your time doing this or it will crack.

Place the main body in the sphere half to line up where the screw will go. Then drill in that location. Do the same for the motor, somewhere, where the wires will freely go through.(See pictures)

Step 4: Add the Spiral "Tree"

The spiral need to be screwed to the main body before anything else, because its on the inside. Use two M2 Plastic threading screws, and mount it to the "back" of the main body, you will see how the hopper aligns with the output of the main body

Step 5: Feed the Motor Wires Through

Now that you have a hole for the wires, feed the motor wires through the hole, so that the motor is placed near where it will be mounted to the main body.

Step 6: Attach the Motor to the Main Body Print

Use the M1.6 screws to attach the metal gear motor to the bottom. Leave the gear off for now.

Step 7: Add the Large Gear and Mounts

Now that the spiral is on, you can place the large gear on top of the main body, fitting inside of the sphere half. Then screw the upper mount, and the lower mount, the secure the main gear in place.

Step 8: Slide on the Small Gear

You can now push on the small gear to the motor shaft. If printed correctly there should only be a small amount of force needed.

Step 9: Screw the Main Body to the Sphere Half

This will hold the main body in the upright position, and allow the large gear to spin freely inside of the ornament. Without it, and it tends to roll around.

Step 10: Add Some Steel "Marbles"

Place some steel "marbles" into the free half of the ornament. Then close the ornament halves together, completing the ornament.

Step 11: Solder a Connector

In my case I cut off an old USB cable and connected it to the motor using the correct polarity(make sure the motor spins counter clockwise). You can decide how you want to power your ornament. I may come up with a better solution in the future.