Singer 628 - Setting the Index Pins

THE CAM STACK (Cont’d)
Removal and Replacement
Remove arm top cover and control panel.
Remove cam stack as previously instructed on
page 14.
Loosen the clamping screw in lower selector arm
by inserting screwdriver through hole in upper arm.
Remove locating screw from plastic cam.
Remove the screw in rear follower arm.
Loosen the rear-stop-bushing set-screw.
Withdraw selector-arm shaft from rear of machine
arm, releasing front selector-arm and return-spring,
plastic cam, spring, rear selector-arm, and rear se¬
lector-arm return-spring.
Remove selector arms from machine.
Remove two followers from index pins.
Replace two followers, and replace selector arms
with cam and return-springs in position, making cer¬
tain that hinged brackets fit into slots in followers.
Replace selector-arm shaft through follower arms.
Replace rear follower-arm screw making certain
that it clamps down on flat part of shaft.
Tighten rear-stop-bushing set-screw securely.
Tighten the damning screw in lower selector-arm.
Rsdiccs ram stack.
Cneck one aajust the release mechcmsm as ; n -
Aa i u stmen r s
Setting the Index Pins
Set stitch selectors at “J” and "R”.
Remove arm top cover and control panel.
At this setting, top surface of two arm followers
should be approximately 1/64 inch below top surface
of c am stack.
NOTE: Position of two arm followers is determined
by height or index pins.
Loosen rear index-pin set-screw.
Raise or lower rear index-pin as required, to bring
top surface of rear follower 1/64 inch below top sur¬
face of cam stack, then tighten set screw securely.
Loosen front index-pin set-screw at front of ma¬
chine arm.
Raise or lower front index-pin as required, then
tighten set screw securely.
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