- 37 -
Breaking upper
thread
- Starting to stitch too fast.
- Improper threading.
- Top thread tension too high.
- Incorrect setting of needle.
- Wrong needles and thread for the fabric.
- Set thread pool and the position
indentation at left side.
- Incorrect setting of bobbin case.
- Needle eye is sharp.
- Burrs on bobbin.
- Burrs on needle hole.
- Start to stitch at a medium speed.
- Re-thread. See page
12
- Adjust top thread tension. See page
15
- Re-set needle. See page
6
- Choose correct needle and thread to suit the
fabric. See page
17
- Adjust position of the indentation to right side.
See page
8
、
、
、
、
9
- Re-set bobbin case. See page
34
- Replace new needle.
- Sand or change bobbin case.
- Sand or change needle plate.
Breaking bobbin
thread
- Down thread improper threading.
- Down thread tension too high.
- Lint in bobbin or shuttle.
- Re-thread. See page
10
、
、
、
、
11
- Adjust down thread tension. See page
15
- Clean bobbin case and shuttle. See page
34
Fabric not
moving
- Stitch length in “O” position.
- Scraps seize-up with feet-dog
- Sewing thread integral convexity
- Didn’t use the special-purpose bobbin.
- Adjust stitch length.
- Clean feed dog. See page
34
- Pull back upper and down threads under of
presser foot.
- Replace special-purpose bobbin.
Machine
jamming
knocking noise
- Thread caught in shuttle.
- Remove and clean shuttle. See page
34
Sewing machine
doesn’t operate
- The machine is not plugged in.
- Machine is not turned on.
- See page
5
- See page
5
Down thread is
pulled above the
cloth.
- Top thread tension too high.
- Upper thread improper threading.
- Down thread improper threading.
- Adjust top thread tension. See page
15
- Re-thread. See page
12
- Re-thread. See page
10
、
、
、
、
11
