Operating instructions

6.1.3 Swing Arm Travel
These adjustments should be checked and performed after every 6 months of
heavy machine use or whenever a swing arm component has been damaged
or replaced.
The two L-brackets on the linkage of each swing arm restrict swing arm
travel when they contact a rubber-padded post screwed to the deck plate.
The two hex screws secure each of the L-brackets to the linkage; the
extremes of swing arm travel can be adjusted by loosening these screws and
sliding the L-brackets. Check the Supply and Take-up swing arms and adjust
as required. Refer to Figure 6-3.
1. Turn off the power to the machine.
2. Extend the REEL CONTROL PCB Assembly (PB-4HQB).
3. Attach a DC Voltmeter (DVM or VOM) to TP3 (swing arm voltage test
point) and any ground (GND) test point.
4. Turn on the power to the machine.
5. Secure the swing arm at its center position. (Dots on the swing arm and
on the transport deck plate indicate the center position.) The Voltmeter
should read 0.0 V ± 0.03 V (30 mV). If it does not, adjust the black
potentiometer under the deck plate by loosening the 2 small phillips
screws that hold the potentiometer bracket in place. Be sure to tighten
securely when completed.
6. Turn off the power and connect the Voltmeter to TP4 on the REEL
CONTROL PCB Assembly. Repeat Steps 4 and 5 for the Supply Swing
Arm.
NOTE: After the above procedure has been completed, the swing arm in its
lower position should be approximately 65 mm (2.55") from the outer rib on
the front of the transport deck plate. When in its upper position, the swing
arm will be approximately 99 mm (3.9") from the same reference point.
Refer to Figure 6-3 for details regarding the measurement positions.
Figure 6-3
Swing Arm Travel Limit Adjustment
65 mm
99 mm
HORIZONTAL POSITION
L BRACKETS
ADJUSTING POINT
ADJUSTING POINT
STOPPER
SWING ARM AT
CENTER OF TRAVEL
SWING ARM AT
BOTTOM OF TRAVEL
SWING ARM AT
TOP OF TRAVEL
LOWER POSITION UPPER POSITION
Section 6 Alignment
6 - 6
October 1990
MTR-90III Operation and Maintenance Manual