Page 20
HQ Sweet Sixteen Service Manual
Figure 3.4
Hook-shaft Timing
Pulley 1
st
Screw
Hook-shaft timing pulley
Tools needed: (2.5 mm handle Allen)
Note:
The hook-shaft timing pulley rotates the opposite
direction as the main shaft timing pulley. Carefully note
the labeled fi rst screw
(Figure 3.4).
Note: The hook-shaft collar does not have a fl at. The fl at is
located on the hook-shaft timing pulley 1st screw.
Important Hook-Shaft Notes
The hook-shaft turns two times per stitch and rotates in
the opposite direction from the main shaft. Please care-
fully note which screw is the fi rst screw in the direction of
motion and on the fl at.
The hook-shaft pulley is set to a specifi c setting from the
end of the shaft to allow proper needle-to-hook distance
adjustment. Adjust the collar to remove axial play, not
the hook-shaft pulley, or the setting can be thrown off,
which may make it so needle-to-hook distance cannot be
adjusted.
The HQ Sweet Sixteen utilizes long collars with two
screws in line to help prevent the collar from tipping
when tightened, causing variation of tightness or play, as
the collar rotates 360º. To ensure that there is no tight-
ness or play, the collar should be checked through a full
rotation until it has minimal tightness and minimal play.
3. Checking and Securing Flats and Screws - Continued
First Screw, First Position Rule
The fi rst screw or fi rst position is ALWAYS located 120°
apart in the direction of rotation from the second screw or
second position. The fi rst screw in direction of rotation
goes on the fl at.
(Figure 3.3)
120
o
Position 2
Direction of
rotation
Position 1
Figure 3.3
Note: First screw in direction of motion goes on the fl at.
The fi rst screw is 120º before the 2nd screw. The 2nd
screw is then 240 degrees before the 1st screw.