SunStar HC Series User Manual page 62

Error Type
Skipped Stitches
Bent needle
Inadequate needle size for
thread
Incorrect installation of needle
Poor timing of needle and
hook
Large gap between needle
groove and hook point
Incorrect lower dead stop
Damaged hook point
Thread feeding is interfered
Inadequate thread
(twist, elasticity, and
flexibility)
Excessive tension or stroke
on the take-up lever spring
Fabric moves with needle -
weak or damaged presser
foot (spring)
Cause
Change needle
Adjust installation
Adjust timing
Adjust the lower dead stop
Use whetstone to adjust hook
point or change hook
Adjust thread tension
For upper thread, change
bobbin or bobbin case
Select right thread for
embroidery
Adjust stroke or tension
Change presser foot spring
Inspection & Repair Reference