|
Problem |
Causes |
Solutions |
|
Upper Thread Breaks |
● Incorrect threading
● Knots or twists in thread
● Tension too tight
● Damaged/old needle
● Needle too small |
● Rethread machine properly
● Replace thread
● Reset bobbin and top thread tension
● Replace needle
● Use correct needle for thread and
application |
|
Bobbin Thread Breaks |
● Bobbin case incorrectly threaded
● Bobbin case incorrectly inserted
● Bobbin does not turn smoothly in
bobbin case
● Lint in bobbin case
● Bobbin tension too tight |
● Remove bobbin and re-thread with
bobbin turning clockwise
● Remove and re-insert bobbin case
● Check that bobbin case and bobbin are
in "round"; replace if necessary
● Clean bobbin case and surrounding
machine area
● Check and reset bobbin tension |
|
Skipped Stitches |
● Thread tension too tight
● Needle damaged
● Needle wrong size
● Sewing machine out of adjustment |
● Reset top and bobbin tension
● Replace needle
● Use correct needle size
● Have sewing machine adjusted for
timing; hook to needle clearance; needle bar height |
|
Frayed Stitches |
● Needle too small
● Tension too tight
● Damaged thread |
● Increase needle size
● Reset tension
● Replace thread |
|
Thread Loops on Bottom |
● Thread not in top tension
● Machine incorrectly threaded
● Top tension too loose
● Burr on hook mechanism |
● Rethread machine with presser foot
"up"
● Rethread machine incorporating take
up lever
● Reset top tension
● Remove burr |
|
Irregular Stitches or Malformed
Stitches |
● Wrong needle size
● Incorrect threading
● Upper tension too loose
● Operator pulling fabric
● Bobbin wound unevenly |
● Ensure correct needle for fabric &
thread
● Un-thread machine and carefully
rethread
● Reset lower and upper thread tension
● Check presser foot pressure
● Rewind bobbin |
|
Fabric Puckers |
● Excessive stitch length
● Needle point is blunt
● Excessive thread tension
● Fabric is too soft
● Thread displacement — too much thread
in a small area
● Fabric not feeding |
● Decrease stitch length
● Change needle often
● Check bobbin and upper tension
● Use stabilizer
● Decrease field density; scale
embroidery designs; increase stitch length
● Check presser foot, needle plate,
feed dogs |
