Singer 271K - Sewing Hook

2. LOOSEN THIS SCREW
1. LOOSEN
7- ) K u
AND RAISE OR LOWER
^BRACKET TO OBTAIN
J- - i
AND
MOVE PLATE
TO
OBTAIN 1/16"
CLEARANCE
TH S SCREU
1/16" CLEARANCE
ROLLER
Fig. 81. Lotch-Tripping Plate Adjustments
CLAMP
LIFTING ARM
VIEWED FROM ABOVE
NEEDLE
COUNTER BALANCE
SET SCREWS
NEEDLE
COUNTER
BALANCE
HOOK
POINT
, .003" TO .005"
CLEARANCE
HOOK POINT
AT 12 O'CLOCK
POSITION
(FRONT)
SET SCREW
i
HOOK SET
SCREWS
'V r?\',
.1
SPROCKET
SET SCREWS
Fig. 82. Setting of Hook.
HOOK
POINT AT
CENTER
OF NEEDLE
HOOK POINT
1/16" ABOVE
NEEDLE EYE
AT .115"
RISE OF NEEDLE,
ON LEFT HAND THROW
Fig. 83. Timing of Hook
SAFETY DEVICES (continued)
Adjustment for release of sewing safety is
made after loosening pitman
screws, shown at
lower right of Fig. 80, and lengthening or short
ening the pitman as required. Securely tighten
both pitman screws.
LATCH-TRIPPING PLATE should be set to
permit upper cutting blades to operate just be
fore clamp check begins to rise.
1.
With machine in "stop" position, loosen
clamp roller bracket screw, shown in Fig. 81,
and raise or lower bracket as required to obtain
approximately 1/16 inch clearance between roller
and clamp lifting arm. Securely tighten screw.
2. Loosen latch-tripping plate screw, shown
in Fig. 81. Move plate toward right or left as
required to obtain 1/16 inch clearance between
latch and plate. Tighten screw and check for
correct action. Cutting blades should
move just
before clamp begins to rise. Reset clearance
between latch and plate as required, before fi
nally tightening plate screw securely.
SEWING HOOK
ASSEMBLY: WVien sewing hook point is at 12
o'clock position (facing operator of machine)
counterbalance should be 90° to right of hook
point, as shown in inset in Fig. 82. Make cer
tain hook body is seated snugly against hook
shaft. Hook assembly will snap into place as it
passes oil ring inside shaft, indicating that it
is correctly seated.
SETTING: Sewing hook should be set with a
clearance of
approximately .003 to .005 inch be
tween needle and hook. Make certain needle is
not deflected by needle guard during this test.
To obtain this setting, loosen two screws in
hub of lower sprocket for driving shaft belt and
loosen the front hook bushing set screw shown
in Fig. 82. Tap bushing as required to obtain
correct clearance between hook point and needle.
Securely tighten hook bushing set screw. Check
timing before tightening sprocket screws.
TIMING: When the needle descends to its lowest
position and rises .115 inch on the left hand
throw of the needle, the point of the hook should
be in the center of the needle, 1/16 inch above
eye of needle.
31
From the library of: Superior Sewing Machine & Supply LLC