The rolling contact surface of the rail, the ball slide and the ball flakes away like scales.
Possible Causes Natural life of a linear guide Improper assembly (misalignment) Poor flatness of the mounting surface Insufficient lubrication or improper lubricant Developed from indentations or corrosion pits on raceway Intrusion of foreign matter and/or water Countermeasures Re-assess model size to increase linear guide lifetime Improve assembly accuracy Improve accuracy of the mounting surface Change to a better lubrication method / Select a suitable lubricant Avoid shock load Review protective covers of equipment / Enhance sealing capability of the linear guide Flaking 1Part: Raceway of a Rail
Symptom: Flaking on the facing raceways of the rail
Cause: Assembly misalignment caused excessive rolling moment as a reaction
Part: Raceway of a Ball Slider
Symptom: Flaking on the facing raceways of the ball slider
Cause: Assembly misalignment caused excessive rolling moment as a reaction
Source: NSK