There is a delay in motion at the reversal points. Unlike backlash, the controller recognizes the delay in motion and compensates.
In this example, the X Axis had a delay in motion and compensated.
The size of the step often varies with the machines feedrate.
- Tight way covers bind and cause friction.
- There is initial torque on the ballscrew at the reversal point. An inadequate amount of torque was applied by the axis drive motor at the axis reversal point. It causes the axis to stick momentarily, as the frictional forces change direction.
- The servo response time of the machine is inadequate on Backlash Compensation. This means that the machine is unable to compensate for the backlash in time. This causes the axis to stop while the machine absorbs the slack.
- There are loose bearings.
- There is twist on the ballscrew.
- The is a problem with the axis lubrication system.
Note: Before you use the Friction Compensation parameter to remove the problem, remove all other possible causes.
Effect on the Machined Part: The effect of a reversal spike is that a circular interpolated cutter path shows a small flat followed by an inward recovery step.