- 36 -
FAULT FINDING CHART
Suspected
problem
Probable cause
Possible easy correction
Threads kink
together under
the fabric.
- Upper thread improper threading.
- Upper tension dial at O position.
- Re-thread. See page
12
- Increase upper thread tension. See page
15
Irregular
stitches
- Incorrect size needle.
- Improper threading.
- Loosen top thread tension
- Pulling fabric.
- Loose presser foot.
- Unevenly wound bobbin
- Nicks or burrs at needle plate.
- Needle plate broken
- Choose correct size needle.
- Re-thread. See page
12
- Tighten top tension. See page
15
- Gently pull the fabric.
- Re-set presser foot.
- Re-wind bobbin. See page
8
、
、
、
、
9
- Cleaning bobbin case and base. See page
34
- Change needle plate.
Breaking needle
- Wrong needles size for the fabric.
- The needle has not installed. The needle
is curving.
- Pulling fabric.
- The needle clamp screw is loose.
- Rotate the pattern dial when needle
insert the fabric.
- Loose presser foot.
- Choose a needle to suit the thread and fabric.
- Re-set needle. See page
6
- Gently pull the fabric.
- Truly locks the needle clamp screw.
- When choice pattern, the needle must above
the fabric.
- Re-set presser foot.
Bunching of
thread
- Upper and lower threads not drawn back
under presser foot before starting seam.
- Pull both threads under and back of presser
foot, then rotates the hand wheel with right
hand.
Puckering
- Incorrect thread tension.
- Upper thread improper threading.
- Using two different sizes or type thread.
- Bent or blunt needle.
- Loosen presser foot
- Fabric too sheer or too soft.
- Re-set thread tension. See page
15
- Re-thread. See page
12
- Use same size and type threads.
- Insert new needle.
- Re-set presser foot.
- Use underlay or tissue paper.
Skipping
stitches
- Incorrect size needle.
- Bent or blunt needle.
- Incorrect setting of needle.
- Improper threading.
- Choose correct size needle for thread and
fabric. See page
17
- Insert new needle.
- Re-set needle. See page
6
- Re-thread. See page
12
