PROBLEM
Skipping Stitches
Breaking Upper Thread
Breaking Bobbin Thread
Fabric not Moving
Machine Jamming Knocking Noise
PROBABLE CAUSE
Incorrect size needle.
Certain knits and synthetics,
Bent or blunt needle,
incorrect setting of needle. Tight upper thread tension.
Starting to stitch too fast.
Improper threading.
Tight upper thread tension,
Incorrect size needle.
Sharp eye in needle.
Nicks or burrs on shuttle.
Nicks or burrs at hole of needle ptate.
Improper bobbin case threading. Lint in bobbin case or shuttle.
Darning plate in place. Stitch Length set at 0. Thread knotted under fabric.
Thread caught in shuttle.
Lint in bobbin case or shuttle.
CORRECTION
Choose correct s_ze needle for thread and fabric. Use "Q NEEDLE',',,.
insert new needle. Reset needle.
Loosen upper thread tension.
Start to stitch at a medium speed.
Rethread machine.
Loosen upper thread tension.
Choose correct size needle for thread and fabric. Insert new needle.
Replace shuttle, or polish off burrs completely, Replace needle plate, or polish off burrs completely.
Check bobbin case threading.
Clean bobbin case and shuttle.
Remove darning plate.
Adjust Stitch Length Control.
Place both threads back under presser foot before beginning to stitch.
Disassemble and clean shuttle.
Clean bobbin case and shuttle.
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