This document shows how to check whether your motors need straightening or not. If they are only slightly crooked, this method will work. If they are grossly out of alignment, you will need to adjust the brackets screws, which is shown in another post.
The photos show only the X motor (the one that runs the length of the table) on my Gammill Premier. Check the Y motor in the same way. The photos show an original motor with the white gears, and a supermotor with the clear belt. Your motor may look slightly different but the mounting block will be the same. It is important to place the straight edge against the mounting block and not the motor cover.
Take the cover off the motor and place a straight edge against the mounting block that has the two set screws, as shown in the photos.
Look along the length of the straight edge and compare it to the straight edge of the track - it should be parallel.
If your straight edge looks like the first picture below and is tilting downwards (probably not as much as this), then give the motor a sharp tap on the right side of the motor with your fist, as shown in the second photo.
Check for straight again.
If your straight edge is tilted up like this picture, give the motor a sharp tap on the left.
Check for straight again. This is usually enough to fix a slightly out of straight motor.
NOTE: if your motors move too easily, then the bracket screws are probably loose and need tightening.
If your motor is straight, next check that the sensor wheel is straight as shown below.
Also move your machine by hand and watch the sensor wheel - if it wobbles or isn't running straight, check the very tiny set screw that holds it in place. The wheel may have come loose.
