3
mesh. Whether tightening or loosening, you are probably best off thinking in terms of setting the mesh anew, rather than
adjusting the existing mesh. The tendency if you try to tighten or loosen an existing mesh by a tiny amount is to overshoot
and put yourself into a back and forth cycle of too tight and too loose. Approach the re-mashing as if you were performing
the original meshing of a newly assembled system, and you will have a greater chance of success.
NOTE:
In mounts from the first production run, you may find that the gear turns freely in one direction and considerably
harder in the other. This can cause poor tracking and/or motor stalls in the more difficult direction, and could eventually
lead to motor damage. The approach is to concentrate on the
difficult direction
of rotation in your adjustments.
At this point, you are ready to start the actual
adjustment. To begin, loosen the two 1/4-20 Gear
Mash Adjustment Screws (SHCS) just enough to
slightly move the worm away from the wheel.
DO
NOT REMOVE THESE BOLTS
, as they hold shims
in place.
NOTE:
There is a third bolt that is inside the motor
housing – behind the receptacle for the Y-cable plug.
When the two bolts indicated above are loosened,
the entire motor / gearbox will pivot a very slight
amount on this third bolt. The bolt is actually part of
a thrust bearing system and MUST remain very tight.
DO NOT try to loosen this bolt. We considered not
even mentioning this bolt so that no one would be
tempted to loosen it. However, we felt it was more
important that you understand how things work. We
trust that you will believe us, and that you will not
loosen this when making your adjustments. Please
see the diagram on page 2.
Pivot the motor gearbox counterclockwise to loosen
the mesh as shown in the diagram on page 2.
Now, gently work the motor / gearbox down into full
mesh by pressing and jiggling the worm slightly by
rocking the worm’s spur gear back and forth. Apply only very light pressure, and press directly over the worm, above the
knurled end cap, rather than out on the back side of the box as shown in the photo above-right.
While pressing down gently, rotate the worm back and forth via its spur gear at least a full rotation in each direction. If one
direction rotates a bit harder than the other, especially in the case of a first production run mount, be sure to rotate the gear
in the more difficult direction to determine the proper mesh. Continue to rotate the gear in the more
difficult direction
as
you gradually apply pressure to the worm
.
(For 1st production run mounts, ignore for now how free the rotation is in the
opposite direction.)
You will reach a point where any continued increase of the pressure on the gearbox begins to affect the ease with which
the worm turns. You should begin to feel this increased tightness in the worm with no more pressure than can be applied
with a single finger. If you have gone too far, simply remove the pressure and continue to turn the worm gear. The
mesh should loosen up a bit as you turn the worm, and you can repeat the process. The idea is to just reach, but NOT to
exceed, the exact point where the worm begins to feel more resistance.
Keeping the light pressure on the motor / gearbox, snug up the two gear mesh adjustment screws. Alternate your
tightening as follows:
1. Start with the screw on the right and bring it to contact - just barely snug.
2. Repeat with the left screw.
3. Bring the right-hand screw to one-half tight.
4. Repeat with the left screw.
5. Fully tighten the right-hand screw.
6. Repeat with the left screw.
Check rotation again in both directions. If free in both directions, retest for backlash as described starting on page 1. If
Motor / Gearbox shown
is from first production run
