12-7
Error Type
Cause
①
Bent needle
②
Inadequate needle size for
thread
③
Incorrect installation of
needle
④
Poor timing of needle and
hook
⑤
Large gap between needle
groove and hook point
⑥
Incorrect lower dead stop
⑦
Damaged hook point
⑧
Thread feeding is interfered
⑨
Inadequate thread
(twist, elasticity, and
flexibility)
⑩
Excessive tension or stroke
on the take-up lever spring
⑪
Fabric moves with needle -
weak or damaged presser
foot (spring)
Inspection & Repair
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
Ref. 5-19, 5-12)
Ref. 11-9, 11-9)
Ref. 5-10, 5-6) 2)
Ref. 5-12, 5-7) 2)
Ref. 5-11, 5-6) 3)
Reference
Skipped
Stitches