Trouble Shooting - Bernina Sewing Machine User Manual

Trouble shooting

In most cases you will be able to identify and remedy faults by
checking the following.
Check whether:
the upper and lower threads are threaded correctly
•
the needle is inserted correctly
•
the needle size is correct – check the needle/thread table p. 42
•
the sewing computer is clean – brush out any thread fluff
•
the hook race is clean
•
any threads are trapped between the tension discs or under the
•
bobbin case spring
the bobbin runs smoothly in the case or if remnants or lint need
•
removing
Upper thread breaks
The upper thread tension is
•
too tight.
The needles are of a poor
•
quality. Ideally needles should
be purchased from your
BERNINA dealer.
The needle is bent or blunt.
•
Poor quality, knotted or dried
•
out thread has been used.
Use the correct spool disc.
•
Stitch plate or hook tip
•
damaged. Take your sewing
computer to your BERNINA
dealer.
Lower thread breaks
The lower thread tension is
•
too tight.
The bobbin is jamming in the
•
bobbin case. Remove and
replace the bobbin.
The hole in the stitch plate
•
has been damaged by the
needle. This must be
repolished by an expert.
The needle is blunt or bent.
•
030595.50.04_0201_a125_EN
Skipped stitches
Wrong needles used. Use only
•
130/705H system.
The needle is blunt, bent or
•
incorrectly inserted.
Push right to the top when
•
inserting.
Needle inserted all the way to
•
the top.
The needle point does not suit
•
the fabric being sewn. If
necessary use a ball point for
knitted fabrics and cutting
point for hard leather.
Needle breaks
Needle clamp screw loose.
•
Fabric taken out in front
•
instead of behind presser foot.
When sewing over thick area,
•
the fabric was pushed with
the needle still in the fabric.
Poor quality thread, unevenly
•
wound or knotted.
See pages 42–44 for infor-
•
mation about needles
Faults
Faulty stitching
Remnants of thread between
•
the tension discs.
Remnants of thread under the
•
bobbin case spring.
Lower thread still threaded in
•
the bobbin case finger.
Sewing computer threaded
•
with foot down.
Incorrect threading. Check
•
upper and lower threads.
Use the correct spool disc.
•
Sewing computer fails to run
or runs slowly
Plug not properly inserted.
•
Power switch in off position.
•
Sewing computer has been
•
standing in a cold room.
Bobbin winder still switched
•
on.
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