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.

• 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