This is an expensive, but worthwhile upgrade. The trackballs now move incredibly smoothly with negligible static friction (stiction). All that this upgrade required was six Bosch ball transfer units (BTUs), two 3D printed trackball holders, two static bearings, and a bit of glue. It is definitely louder than the stock configuration with only static bearings, but not as bad I had been expecting based on comments I had read online. As mentioned, it was rather expensive, costing me about 100€ after shipping for the six BTUs alone. But reading comments from other users who have done similar upgrades, it is well worth the extra cost (over cheaper BTU models) for something that you use daily. Printing the trackball holders (which were modeled by a fellow user) was also extremely simple. Printing certain Svalboard components requires a tightly calibrated printer, but the trackball holders do not. I was able to print these after dusting off an Ender 3 that has been sitting unused on a shelf for a couple years.

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  • BTU used: Bosch Rexroth R053010810 Ball Transfer Unit Ball Transfer Unit Ku-B8-Ofk
  • Public Onshape repo for the trackball holder 3D model: Svalboard Open Trackball BTU HACKING - PMW3360/3389 - 2025-09-10
  • Stabilizer bearing: 1/8-inch Ceramic Bearing Balls ZrO2 Zirconium Oxide Ball G5
    • SatyrSack@quokk.auOPEnglish
      3·
      3 days ago

      In general, yes. Using ceramic static bearings is standard for trackballs because it is more smooth than the ball just grinding against plastic or something.

      This design for the trackball holder is made to use three BTUs as the primary bearings, then includes a spot for a single static bearing that just serves to add stability. That static bearing does really feel optional here, as the trackball touches just the three BTUs 99% of the time. Quick movements that jerk the ball a bit and make it touch the static bearing are rare, and could probably just be avoided by adjusting your pointing technique to just not let that happen.

      Here is a blog post comparing different types of common trackball bearings: https://kbd.news/Trackball-bearing-comparison-1757.html