Bernina aurora 430 Service Manual page 84

82
Sewing-off
Sewing-off is a way of checking whether the
adjustments made have had the desired
effect, and that the machine is functioning
correctly.
The following stitches should be checked in
sequence using the appropriate criteria.
1) Straight stitch
• Is the thread regulator spring being
moved correctly?
• Is the row of stitching straight?
• Is the thread feed regular?
2) Zigzag (default values)
• Is the stitch formation symmetrical?
• Is the thread feed regular?
• Is the fabric free from puckering?
3) Satin stitch
• Is the stitch formation symmetrical?
• Is the thread feed regular?
• Is the fabric free from puckering?
4) Running stitch
• Is the stitch formation symmetrical?
• Is the thread feed regular?
• Is the fabric free from puckering?
External cleaning
Attention!
Never use alcohol, benzine, spirits or any other corrosive fluids, or abrasive pastes!
Electrostatic charging may occur during cleaning. To prevent this, use antistatic office-
equipment cleaning agents.
We use and recommend BASF's SURFACE CLEAN surface cleaner. It forms a protective film
against static electricity, and is suitable for both plastic and metallic surfaces.
5) Balance using '9' for testing
• Is the stitch formation symmetrical?
• The stitch formation in the '9' must be
closed.
6) Any other stitch (e.g. honeycomb stitch)
• Is the stitch formation symmetrical?
• Is the thread feed regular?
• Is the fabric free from puckering?
7) Buttonhole
Standard buttonhole
• Is the stitch formation symmetrical?
• Are the beads of equal length?
• Is the feed correct?
Automatic buttonhole
• Is the stitch formation symmetrical?
• Are the beads of equal length?
• Is the feed correct?
Keyhole buttonhole
• Is the stitch formation symmetrical?
• Are the beads of equal length?
• Is the feed correct?
• Is the stitch formation of the eyelet
part symmetrical?
a) BSR Mode
• 1 and Mode 2 if applicable
8) Sew-off samples for the customer
At the end of the service, a sample is
prepared for the customer so that they
can see how the machine sews after the
service or repair. This sample should
contain the following stitches:
• Straight stitch
• Zigzag stitch
• Running stitch and
• any other stitch
• Buttonhole
Should the customer have complained
about the buttonhole, or any specific
stitch / function, these should also be
sewn on another piece of fabric and
included.
10)EC on PC
• USB connection