TABLE OF CONTENTS One of the most often neglected precautions relevant to motor alignment is the firming up of soft legs.
Somewhere in Basic Geometry I suspect there is a law that (in essence) states:
| Note | Any three points share a single flat plane. If a fourth point is added anywhere in the pattern, any one of the four points can be adjusted to share the common plane of the other three. |
Assuming this is true, it follows that any one of the four motor feet on an ordinary electric motor may be firmed up via the placement or removal of shims (as applicable) to render the motor equally supported by all four feet. While this geometric law might give you a certain freedom of choice, it s practical to be very selective about which motor foot (or feet) will receive or sacrifice additional shims during the firming up of the motor feet.
Observe the motor in FIGURE (1). It s quite obvious that one leg, D is 1/2" short. (In alignment jargon, the short leg is said to be soft ). It s also obvious that if a 1/2" shim were placed under that one motor foot, all four feet would firmly support the motor. However, when a soft leg is only a few mils short, the correct shims for correcting that leg becomes much less obvious. This is the kind that if not corrected can generate migraine pains for the mechanic.
By using what is known to some mechanics as the Rock-a-bye ...
