Spindle imbalance

Over the course of a year, the equipment owners replaced three high quality Hitec spindles, as the spindle bearing would fail approximately every four months for an unknown reason. After attaching a sensor, a bearing fault was detected. Upon replacing the spindle and bearing with a new one, a very clear tool imbalance was identified, which had caused the recurring bearing failures. After correcting the tool imbalance, the failures did not recur.