CHECKING
SUSPECTED PROBLEM PROBABLE CAUSE
IRREGULAR
STITCHES
BREAKING
NEEDLE
BUNCHING OF
THREAD
PUCKERING
Incorrect size needle.
Improper threading.
•-.Loose upper thread tension.
Pulling fabric.
Light pressure on presser foot.
Loose presser foot.
Unevenly wound bobbin.
Nicks or burrs at needleplate opening.
Pulling fabric.
Incorrect size needle.
Incorrect setting of needle.
Loose presser foot.
Upper and lower threads not drawn back under presser
foot before starting seam.
Incorrect thread tension(s).
Light pressure on presser foot.
Using two different sizes or kinds of thread.
Bent or blunt needle.
Loose presser foot.
Fabric too sheer or too soft.
SKIPPING
STITCHES
BREAKING UPPER
THREAD
BREAKING BOBBIN
THREAD
Incorrect size needle.
Certain knits and synthetics.
Bent or blunt needle.
Incorrect setting of needle.
Tight upper thread tension.
Light pressure on presser foot.
Starting to stitch too fast.
Improper threading.
Tight upper thread tension.
Incorrect size needle.
Sharp eye in needle.
Nicks or burrs at needleplate opening.
Improper bobbin case threading.
Lint in bobbin case or shuttle.
FABRIC NOT
MOVING
MACHINE JAMMING,
KNOCKING NOISE
MACHINE DOES
NOT SEW
Feed cover plate attached.
Light pressure on presser foot.
Thread knotted under fabric.
Thread caught in shuttle.
Damaged needle.
'i
Bent needle plate.
Hand wheel not returned to stitching position.
Power cord not connected.
Power/light switch off.
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