4
CONDITION
CAUSE
HOW TO FIX
REFERENCE
3. BREAKING 1. INITIAL SEWING SPEED IS START WITH MEDIUM SPEED.
UPPER
TOO FAST.
THREAD 2. THREAD PATH IS
USE THE PROPER THREAD
INCORRECT.
PATH.
3. NEEDLE IS BENT OR DULL. REPLACE WITH A NEW NEEDLE.
4. UPPER THREAD TENSION IS ADJUST UPPER THREAD
P.10
TOO STRONG.
TENSION CORRECTLY.
5. NEEDLE SIZE IS
USE APPROPRIATE NEEDLE
INAPPROPRIATE FOR
AND THREAD FOR FABRIC
FABRIC.
IN USE.
6. NEEDLE EYE IS WORN.
CHANGE THE NEEDLE.
7. NEEDLE HOLE IN NEEDLE
REPAIR THE HOLE OR
PLATE IS WORN OR BURRED. REPLACE THE NEEDLE PLATE.
4. BREAKING
1. INCORRECTLY THREADED THREAD BOBBIN CASE
BOBBIN
BOBBIN CASE.
CORRECTLY.
THREAD 2. TOO MUCH THREAD IS
ADJUST THE POSITION OF
WOUND ON THE BOBBIN.
STOPPER.
3. LINT IS STUCK INSIDE THE CLEAN THE HOOK RACE.
HOOK
RACE.
4. THREAD QUALITY IS
CHANGE TO A HIGH QUALITY
TOO LOW.
SEWING THREAD.
5. THREAD IS JAMMING
CLEAR OUT THE JAMMING
AROUND THE BOBBIN.
THREAD.
6. BOBBIN THREAD TENSION IS ADJUST BOBBIN THREAD
P.11
TOO STRONG.
TENSION CORRECTLY.
5. NEEDLE
1. NEEDLE IS HITTING THE
SEE MECHANICAL
P.14
BREAKS
NEEDLE PLATE.
ADJUSTMENT “NEEDLE DROP.”
2. NEEDLE IS BENT OR WORN. CHANGE THE NEEDLE.
3. NEEDLE IS HITTING THE
SEE MECHANICAL
P.15, 16
SHUTTLE RACE.
ADJUSTMENT “CLEARANCE
BETWEEN NEEDLE AND SHUTTLE”.
4. THE FABRIC MOVES WHILE SEE MECHANICAL
P.13
THE NEEDLE IS PIERCING ADJUSTMENT “NEEDLE SWING”.
IT, OR THE NEEDLE ZIGZAGS
WHILE IN FABRIC.
5. FABRIC IS BEING PULLED TOO GUIDE THE FABRIC GENTLY
STRONGLY WHILE SEWING. WHILE SEWING.
WHAT TO DO WHEN
Summary of Contents for NH15
Page 1: ...1 SERVICE MANUAL MODEL NH15 PARTS LIST...
Page 23: ...23 WIRING 1 WIRING FOR MACHINE SOCKET UNIT L M M MOTOR L LAMP M L 120V 240V...
Page 34: ...34 MODEL NH15 PARTS LIST 1 2 3 4 4 5 6 7 8 9 10 11 12 13 14 8 4 15 16 17 8 8 18 19...
Page 38: ...38 MODEL NH15 PARTS LIST 1 2 3 9 5 8 6 7 4...
Page 40: ...40 MODEL NH15 PARTS LIST 2 8 1 4 5 7 6 3 9 10 11...
