Additional parts:

• 6x3 Neodymium Magnet x7
• 608zz bearing
• some glue maybe

Use 7 6x3 magnets (like in the Nevermore filter, Klicky Probe and many other prints) and glue them in the wheel and base respectively. If you dont glue them, they might wobble and create sounds.

Use a 608zz skateboard bearing on the inside. The tolerances for this are spot on, so calibrate your machine well before trying. (Or mine might be weird, they are 8,1mm inner hole diameter). You might also put some lighter grease in the bearing to make it run a bit longer