Inspection Procedure; First Inspection Period; Second Inspection Period - IBM Selectric Maintenance Manual

INSPECTION PROCEDURE
Inspection
Period
2
3
4
FIRST INSPECTION PERIOD
CYCLE CLUTCH
Inspection Area
Cycle Clutch
Tilt Mechanism
Ribbon Feed Mechanism
Impression and Alignment
Rotate Mechanism
Detenting
Selection Magnet Units
Cycle Clutch Ilnlatching
Operational Magnet Units
Pusher Unit
Contact Cleanin!?
Escapement
Motor Drive and Carrier Return
Indexing and Paper Feed
Shift (Enter Mechanism)
1. Latch height: Measure with #3 scribe line on Hoover-
.ometer.
2. Cycle shaft collar: The cycle clutch
shoul~·begin
to \
slip approximately 15
0
before the check pawl detents.
Hand cycle the machine, using a -5 rotate; O-tilt char-
acter.
3. Nylon stop: Ad just for four degrees rotation or over-
throw when the cycle shoft is latched home.
4. Shaft end play: .001" - .003".
5. All gears: Minimum play, no binds, screws tight.
6. Print-shaft timing: The keyway should be toward the
dowel pin on the carrier.
TILT MECHANISM
1. Check the tilt motion: Use TO and T3.
2. Check the tilt detenting: Use a T3 character and hal f-
cycle the machine. Place a slight pressure on the rear
of the tilt ring. Remove the detent, and allow it to re-
turn slowly. The ring should move ~o more than .005".
RIBBON FEED MECHANISM
1. A -5 rotate, I-tilt character should strike the ribbon
1/16" from the bottom in the high lift position.
2. Check for enough tension of the ribbon-feed mechanism-
ratchet-brake springs to hold the ribbon ratchets in a
rotated position, to overcome positively the action of
the centering spring.
3. The ribbon-feed pawl should hold the reversing inter-
poser within .005" - .010" of its total travel with the
ribbon-feed cam on its high point and the ribbon mech-
anism set for a reversing operation. Positive two-tooth
feed plus .010" overthrow should result.
SECOND INSPECTION PERIOD
DYNAMIC CHECK
1. a. Move the roller to the top of the compensator.
b. Repetitively type minus-five selections. The roller
should return to rhe compensated position. If wear
has caused the compensator foller to drop almost to
the bottom of the slot, hal f-cycle a -5 character.
Ti It the machine up on its back. Raise the nylon
wedge manually, and tighten the rotate link until
there is 1/16" travel left in the nylon wedge.
Tighten the nuts on the rotate I ink. Note: The
compensator nylon wedge must be clean and free of
oi I. I f it does not drop easil y
I
or appears to be
oily or dirty, flush the wedge with cleaning fluid
and wi pe dry.
2. The general condition of all selection and outout-motion
adjustments can be checked by making a complete strike-
up of the keyboard. Type back over it several times,
watching for signs of misalignment with the previously
typed characters. If alignment is not satisfactory, the
need for closer inspection can be met by observing the
dynamic detenting action of the typehead.
Manually half-cycle the following selections one at a
time, and observe the latches:
O-rotate, 1 -ti I t character
-5 rotate, l-ti I t character
+ 1 rotate, O-ti I t character
+2 rotate, O-til t character
+3 rotate, O-tilt character
These characters allow each latch to be checked in-
dividually. Observe that the selected latches clear
the bail fully, and do not snap off. Observe that the
nonselected, or operated, latch seats fully on the bail,
does not jump
Offi
and makes the correct selection.
IMPRESSION AND ALIGNMENT
1. The rotate and ti It tapes must be free from kinks and
nicks.
2. Check for binds or excessive play in the tilt and rotate
detents with respect to their guides. Check the tilt ring
in relation to its pivots, and the upper ball socket with
respect to the ti It-ring spacer.
3. Check for smooth compensator action.
Static check:
a. Half cycle a -5 selection with the typehead removed.
b. Pull the rotate arm out until it is completely removed
from the compensator leaf spring.
1-10
c. Release the rotate arm. This should cause the leaf
spring to collapse against the power frame.
ROTATE MECHANISM
1. Half-cycle a O-rotate, 3-tilt character and observe the
detenting. Folloy, the same procedure for a +5 rotate,
3-tilt character
I
a -3 rotate, 3-tilt character
I
and a -5
rotate
I
3-tilt character.
The variance in bandwidth of these characters should not
exceed .030".