Necchi 590 Instruction Manual page 78

5. PERFORMANCE CHECKLIST
GENERAL PROBLEMS
Machine does not sew.
* Power switch is turned off.
- Turn on the switch.
* Assure foot controller plug is fully engaged
(pushed into its socket).
* Buttonhole lever is not raised when sewing stitch
patterns.
– Raise buttonhole lever.
* Buttonhole lever is not lowered when sewing
buttonhole.
– Lower buttonhole lever.
* Bobbin winder is engaged.
– Disengage bobbin winder (see page 20 - 21).
Machine jams/knocks.
* Thread is caught in hook.
- Clean hook (see page 70 - 71).
* Needle is damaged.
- Replace needle (see page 32).
Fabric does not move.
* Presser foot is not lowered
- Lower presser foot.
* Stitch length is too short
- Lengthen stitch length.
STITCHING PROBLEMS
Machine skips stitches.
* Needle is not all the way up into needle clamp
(see page 32).
* Needle is bent or blunt.
- Replace needle (see page 32).
* Machine is not threaded correctly
(see page 24 - 25).
* Thread is caught in hook.
- Clean hook (see page 70 - 71).
Stitches are irregular.
* Needle size is not correct for thread and fabric
(see page 30 - 31).
* Machine is not threaded correctly
(see page 24 - 25).
* Top thread tension is too loose
(see page 34 - 35).
* Fabric is being pulled or pushed against machine
feeding action.
- Guide it gently.
* Bobbin has not been wound evenly.
- Rewind bobbin.
Needle breaks.
* Fabric is being pulled or pushed against machine
feeding action.
- Guide it gently.
* Needle size is not correct for thread and fabric
(see page 30 - 31).
* Needle is not all the way up into the needle clamp
(see page 32).
* Too much thread appears on the underside of
stitching.
* Upper thread not correctly thread
(see page 24 - 25).
76
THREAD PROBLEMS
Thread bunches.
* Top and bobbin threads are not drawn back under
presser foot before starting seam.
- Draw both threads back under presser foot about
4" (10 cm) and hold until a few stitches are formed.
Needle thread breaks.
* Machine is not threaded correctly (see page 24 - 25).
* Top thread tension is too tight (see page 34 - 35).
* Needle is bent.
- Replace needle (see page 32).
* Needle size is not correct for thread and fabric
(see page 30 - 31).
Bobbin thread breaks.
* Bobbin case is not threaded correctly
(see page 21 - 25).
* Lint accumulates in bobbin case or hook.
- Remove lint (see page 70 - 71).
Fabric puckers.
* Top thread tension is too tight.
- Adjust thread tension (see page 34 - 35).
* Stitch length is too long for sheer or soft fabric.
- Shorten stitch length.