Linear Edger - Electric Actuators

McDonough Linear Edgers are available with optional electric actuators that allow us to achieve very high saw set speeds with tremendous accuracy. These actuators contain an internal ballscrew assembly that drives the rod to its target position while an internal high-count encoder keeps track of the number of turns on the screw and therefore the rods position. As these actuators will see tens of thousands of strokes over their service life it is normal for the internal ball-screw to develop some wear and therefore a small amount of measurable play at the end of the rod.

The easiest way to measure this is to use a dial indicator set up against the end of the rod to measure a 1/2" stroke both toward and away from the dial plunger. As the actuator wears you will find that the rod will actually move slightly less than the target 0.500" in each direction that it is being commanded to move. Fortunately, due to this service wear being common to many types of actuators, electric and otherwise, we have the capability to tune the actuator to compensate for that play or “backlash” by adding or subtracting that distance to the commanded move depending on the direction of travel. If your machine is equipped with electric actuators then your machine interface likely has provisions for you to change the “mechanical backlash” setting for each individual saw. By keeping this number in tune with the actual measured numbers on each actuator rod you will realize precise saw positioning performance over the life of your machine.