AT&T Bell System Plant Series Adjustment Procedure page 7

3.02 (Continued)
M-7 Bind Ili8Y be due to a roughened,
bent or dirty plunger rod. To
determine whether the plunger rod is
bent, revolve it and watch for side
~otion of the rubber plunger. At the
same time it is advisable to see whet3er
the rubber plunger is worn. Whenever
necessary take the key a~ert in the fol-
lowi
WI;
manner.
M-8 Loosen the mounting screws with
the 3-l/2" cabinet screw-driver
and then raise the key above the key-
shelf without unsoldering any form wires.
Remove the key button, lock washer and
lock nut as described in paragraphs M-2
and M-3 and proceed as follows:
Jl-9 Loosen the spring
esse~bly
mount-
ing block screws with the 3-l/2"
cabi~et screw-driver and remove the
spring assembly mounting block, the heli-
cal spring ·and. finally the plunger rod.
M-10 If the bind is merely due to a
dirty plunger rod, clean it and
the plunger slot thoroughly with pe-
troleum spirits. When thoroughly dry,
rub a small amount of KS-6232 oil over
the plunger rod and wipe it off with
the KS-2423 cloth.
M-11 Replace any plungers which show
flat spots. If, however the
bind is due to a bent or roughened
plunger rod replace it with e new one.
Reasser1ble the key.
M-12
I f
the bind still occurs examine
the key to determine whether it
is caused by friction between the
phosphor bronze buffer plates and the
plunger rod. This trouble and trouble
caused by worn bushings allowing dirt to
enter around the plunger rods may be de-
tected by removing the key from the key
shelf and holding the slide plate over
against the slide plate operating sprine
so that the plungers operate clear of
the slide plates. Any excessive fric-
tion will then be noted. If friction
occurs and is caused by the buffer
plates, change the key.
M-13 In resetting the key buttons,
turn down the lock nut as f.ar as
it will go and set the button so that it
will line up with the button on adjacent
keys. Place three or four thicknesses
of the KS-2423 cloth over the button,
grip it firmly with the No. 210 pliers,
and then while holding it firmly tighten
the look nut up against the key button.
j3.o3
~.04
IS~
2-D, SECTION 032-721-701
SLIDE PLATE OPERATING SPRING
TE:-;siON
(Rq. 2.
o
3)
PLTJ11' G ER R~EASE
(Rq.2.04)
M-1 See that the slide plate has full
travel when any plunger is de-
pressed. Foreign matter between the
slide plate and key base will hamper the
movement of the slide plate and thereby
prevent the proper release of a plunger
from the locked to the normal position.
Place a few drops of petroleum spirits
between the slide plate and key base and
operate the slide plate by hand a number
of times, then take a toothpick which
has been dipped in petroleum spirits and
remove whatever dirt may remain. Exer-
cise care not to break the toothpick so
as to leave portions of it between the
key base and slide plate. At the same
time remove any dirt that might have
collected on the rollers.
,--------Slide Plate
\
Operatine Sprine
~--Slide
Plate
Fig. 9 - Method of Gauging Slide
Plate Operating Spring
Tension
M-2 A weakened or dameged slide plate
spring will result in failure to
lock the plungers in the operated posi-
tion. To increase the tension on a weak
spring adjust it close to the base of
the spring with the duck-bill pliers so
that a greater pressure will be exerted
against the slide plate. Damaged
springs should be replaced using the
Nos. 206 and 207 offset screw-drivers
to remove the mounting sorew.
Page 7