CAUTION: a disassembled carriage can easily start dropping ball bearings. Handle it carefully, and read the instructions until the end before starting.

Remove one of the end caps of your linear rail by pulling it out.

Turn the rail upside down.

Carefully slide the carriage out of the rail.

Check if the amount of ball bearings on both cavities of your carriage is the same.

Each cavity should be filled with bearings, with some left-over space. Without removing them, separate 2 ball bearings and make as wide a gap as you can between them. The left-over space should be approximately as wide as one ball bearing. If you find a gap wider than this, your linear rail is missing ball bearings.

If the ball bearings are looking good, lubricate your carriage.

If after lubrication and reassembly, your rail is still not smooth enough, try to swap the carriage with another rail, in order to pinpoint if the issue is in the carriage, or in the rail. Please contact our support.