PERFORMANCEPROBLEMS
CHART
What to Do When
PROBLEM
PROBABLE
CAUSE
CORRECTION
Incorrect size needle.
Choose correct size needle for thread and fabnc.
Skipping Stitches
Bent or blunt needle.
Insert new needle.
Incorrect needle instaiation.
Reinstall needle.
Tight upper thread tension,
Loosen upper thread tension.
Breaking Upper Thread
Starting to stitch too last.
improper threading.
Tight upper thread tension.
incorrect size needJe.
Sharp eye in needle,
Nicks or burrs on shuttle.
Nicks or burrs at hole st needle plate.
Start to stitch at a medium speed,
Rethread machine.
Loosen upper thread tension.
Choose correct size needle for thread and fabnc.
insert new needle.
Replace shuttle, or polish off burn completely.
Replace needle plate, or polish off burrs completely.
Breaking Bobbin Thread
Improper bobbin case threading.
Check bobbin case threading.
Lint in bobbin case or shuttle.
Clean bobbin case and shuttle.
Darning plate in place.
Remove darning plate.
Fabric not Moving
Stitch Length set at "'O".
Adjust Stitch Length Control.
Thread knotted under tabric.
Place both threads back under presser toot betore beginning to stitch,
Machine Jamming; Knocking Noise
Thread caught in shuttle.
Disassemble and clean shuttle.
Lint in bobbin case or shuttle.
Clean bobbin case and shuttle.
Incorrect size needle.
tmproper threading.
Loose upper thread tension.
Pulling tabne.
Loose presser foot.
Unevenly wound bobbin.
Nicks or burrs at hole st needle plate.
lrreguIar Stitches
Use correct size needle tot thread and fabric.
Rethread machine.
Tighten upper thread tension.
Do not pull fabnc; guide it gently.
Reset presser toot.
Rewind bobbin.
Replace needle plate, or polish off burrs completely.
Pulling tabnc.
Do not pull fabric; guide it gently.
Breaking Needle
Incorrect size needle.
Choose correct size needle for thread and fabne.
Incorrect needle instalation.
Reinstall needle.
Loose presser toot.
Tighten presser toot,
Upper and lower threads not drawn back
When starting a seam be sure to draw both threads under and
Thread Bunching
under presser foot betore starting seam.
back st presser foot about 4" and hold until a few stitches are formed.
incorrect thread tension (s).
Reset thread tension(s).
Using two different sizes or kinds of thread.
Upper thread and bobbin thread should be same s_ze and kind.
Puckenng
Bent or blunt needle.
Insert new needle.
Loose presser foot.
Tighten presser toot.
Fabric very sheer or very soft.
Use underlay of tissue paper.
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