IBM Selectric - Tabulator Set and Clear

Cam At High Point
FIGURE 157. Index Link Stud Adjustment
3. Upper Index Pawl Stop - With the index cam latched
adjust the upper index pawl stop so that the index pawl
clears the ratchet by .015" to .030" (Fig. 158).
4.
FIGURE 158. Upper Index Pawl Stop Adjustment
Multiplying Control Lever
a. As 0 preliminary setting, position the multiplying
control lever stop front to rear so that its elongated
hole is centered (Fig. 159). The ad justment pro-
vides an average leverage ratio for the multiplying
lever. Subsequent adjustments may require that the
front to rear position be changed slightly.
b. Adjust the multiplying control lever vertically to
just
clear the bottom edge of the multiplying lever
when it is moved from the single to the double index
position. The adjustment should be made with the
index cam lajched. Keep the high point of. the
eccentric toward the front of the machine.
c. Adjust the multiplying control lever stop front to
rear so that two full teeth of motion is given the in-
dex pawl after it starts to drive the platen (Fig. 159).
54
FIGURE 159. Index Travel Adjustment
CAUTION: Be sure that the indexing action is not
choked off by the platen overthrow stop.
5. Platen Overthrow Stop - Ad just the stop forward or back
so that .005" clearance exists between the stop and the
pawl when the cam is on its high point (Fig. 159).
6. Index Selection Lever - Ad just the index selection lever
link so that the lever lines up with the double mark on
the case when the lever is in the double I ine space posi-
tion.
1.
TABULATOR SET AND CLEAR MECHANISM
Tab Rack Be Ilcrank - Ad just the be Ilcrank attached to
the left end of the tab rack so that an unset tab stop is
centered between the tab lever pawl and the tab set lug
on the escapement bracket (Fi g. 160). Latch the tab
lever to the rear to check this ad justment.
Tab Stop Not Set
III
~FIGURE 160. Tab Rack Bellcrank Adjustment