PERFORMANCEPROBLEMSCHART
What to Do When
PROBLEM
PROBABLE
CAUSE
CORRECTION
Incorrect size needle.
Choose correct size needle for thread and fabric.
Skipping Stitches
Bent or blunt needle.
Insert new needle.
Incorrect needle instalation.
Reinstall needle.
Tight upper thread tension.
Loosen upper thread tension.
Breaking Upper Thread
Breaking Bobbin Thread
Fabric not Moving
Machine Jamming; Knocking Noise
Irregular Stitches
Breaking Needle
Thread Bunching
Puckering
7O
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 plate.
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 bum completely.
Replace needle plate, or palish off burrs completely.
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.
Stitch Length set at "'O".
Adjust Stitch Length Control.
Thread knotted under fabric.
Place both threads back under presser foot before beginning to stitch.
Thread caught in shuttle.
Disassemble and clean shuttle.
Lint in bobbin case or shuttle.
Clean bobbin case and shuttle.
Incorrect
size needle.
Improper
threading,
Loose upper
thread
tension.
Pulling fabric.
Loose presser
foot.
Unevenly
wound
bobbin.
Nicks or burrs
at hole of needle
plate,
Pulling fabric.
Incorrect size needle.
Incorrect needle instalation.
Loose presser foot.
Upper and lower threads net drawn back
under presser foot before starting seam.
Incorrect thread tension (s).
Using two different sizes or kinds of thread.
Bent or blunt needle.
Loose presser foot.
Fabric very sheer or very soft.
Use correct size needle for thread and fabric.
Rethread machine.
Tighten upper thread tension.
Do not pull fabric; guide it gently.
Reset presser foot.
Rewind bobbin.
Replace needle plate, or polish off burrs completely.
Do not pull fabric; guide it gently.
Choose correct size needle for thread and fabric.
Reinstall needle.
Tighten presser foot.
When starting a seam be sure to draw both threads under and
back of presser foot about 4" and hold until a few stitches are formed.
Reset thread tension(s).
Upper thread and bobbin thread should be same size and kind.
Insert new needle.
Tighten presser foot.
Use underlay of tissue paper.
