CONDITION
CAUSE
HOW TO FIX
REFERENCE
5. NEEDLE
BREAKS
4. THE FABRIC MOVES
WHILE THE NEEDLE IS
PIERCING IT, OR THE
NEEDLE ZIGZAGS WHILE
IN FABRIC.
5. FABRIC IN BEING PULLED
TOO STRONGLY WHILE
SEWING.
SEE MECHANICAL
ADJUSTMENT “NEEDLE SWING”.
GUIDE THE FABRIC GENTLY
WHILE SEWING.
P.10
6. NOISY
OPERATION
1. BACKLASH BETWEEN
SHUTTLE HOOK GEAR
AND LOWER SHAFT GEAR
IS TOO GREAT.
2. LOWER SHAFT GEAR IS
LOOSE.
3. INAPPROPRIATE BELT
TESION.
4. UPPER SHAFT GEAR IS
LOOSE.
5. NOT ENOUGH OIL.
SEE MECHANICAL
ADJUSTMENT “CLEARANCE
BETWEEN NEEDLE AND HOOK
(NO.2)”.
ELIMINATE THE LOOSENESS.
SEE MECHANICAL
ADJUSTMENT “MOTOR BELT
TENSION”.
ELIMINATE THE LOOSENESS.
OIL ALL MOVING PARTS.
P.14
P.24
7.DEFORMATION
PATTERN
1. INAPPROPRIATE ZIGZAG
SYNCHRONIZATION.
2. INAPPROPRIATE
DISENGAGEMENT OF AM
FOLLOWER.
3. UPPER THREAD TENSION
IS TOO STRONG.
4. INAPPROPRIATE FEED
BALANCE.
SEE MECHANICAL
ADJUSTMENT “NEEDLE SWING”.
SEE MECANICAL ADJUSTMENT
“DISENGAGEMENT OF CAM
FOLLOWER”.
ADJUST UPPER THREAD
TENSION CORRECTLY.
SEE MECHANICAL
ADJUSTMENT “FEED BALANCE
ON STRECH STITCH”.
P.10
P.20 - P.23
P.7
P.17
WHAT TO DO WHEN
3