SINGER 331K4 - Manual (Page 13)

13
TO SET THE NEEDLE BAR AT THE
CORRECT HEIGHT
PREPARATION:
Remove face plate, slide plate and throat plate. See
that needle is correctly set in needle bar, as instructed
on page 5.
CHECK:
When shuttle point passes centre of needle, top of
needle eye should be approximately 1/16 inch below
point of shuttle. See Fig. 29.
ALTERNATE CHECK:
The gauge distance from throat plate seat to needle
stop in needle bar (at lowest point) should be 1.004
inches, as indicated in Fig. 30.
SETTING:
Loosen clamping screw F, Fig. 30. Raise or lower
needle bar, as required. Then securely tighten screw F.
Replace throat plate, slide plate and face plate.
TO TIME THE SHUTTLE
EXPLANATION:
Timing of shuttle is fixed at the factory for normal
sewing conditions at a 1/10 inch loop lift.
This is accomplished by pinning the shuttle driver at
one end of the oscillating shaft and then pinning crank
G, Fig. 31 at the other end of the shaft at the specified
timing location.
TO CHECK THE TIMING:
Turn the machine pulley over toward you until needle
bar descends to lowest point and then rises approxi­
mately 1/10 inch.
At this setting, for normal sewing, the point of the
shuttle should be at the centre of the needle as shown
in Fig. 29.
TO RE-SET THE TIMING:
When it becomes necessary to replace one or more
of the shuttle driving parts or to alter the timing to suit
a particular sewing condition, remove pin H, Fig. 31.
Loosen set screw J, Fig. 31.
Move point of shuttle to desired timing position and
securely tighten set screw J in crank G.
Plug pin hole in shaft and drill new hole to receive
pin in desired location.
Insert pin H.
A 4 SHUTTLE POINT
CENTER
VW
I
Fig. 29. Relationship of Shuttle Point to Needle Eye
Fig. 30. Setting Needle Bar Height
Fig. 31. Setting the Oscillating Shaft Crank
to Time of Shuttle