Our Class 5 (C5) bearings are lifetime-lubricated and feature an adjustable preload for optimal performance. These precision bearings provide superior accuracy, tighter tolerances, smoother and quieter operation, and cooler running temperatures. The bearings are factory-set with a preload of .0002", rated for continuous operation up to approximately 4,000 RPM. For higher-speed applications, up to 10,000 RPM, a slightly looser preload of .0003" may be required.

We do not recommend customers attempt to replace the headstock bearings themselves. Proper bearing installation requires the use of specialized fixtures to ensure perfect spindle and bearing alignment.

If you are unable to press the bearings in yourself, you may return your headstock to our facility for professional replacement. Please contact our customer service department at kim@sherline.com to obtain an RMA number before sending your headstock in for service.
Note: Service fees apply.

Learn more about our specialized tools and procedures for setting the headstock bearing preload: PDF: Replacing Headstock Bearings Video: Setting the Headstock Bearing Preload