Sewing-Off Guidelines - Bernina B 590 Service And Maintenance Manual

3.9 Sewing-off guidelines

Sewing-off is a way of checking the properly set machine.
Requirement:
• Properly set machine according to the respective Service- and Maintenance Manual.
• Increased wear and tear of parts could cause deviations. Such parts must be replaced.
• All criteria have to be met without changing the balance. If deviations occur, adjust the balance
according to the respective Service- and Maintenance Manual.
The following materials meet the sewing-off guidelines, and are therefore recommended for use when
sewing-off.
Sewing-off fabric: Cretonne 100% cotton, warp = 17, weft = 18 threads /¼ square inch, thread 20/20 2-
ply.
Needle thread: Amann / Mettler Seralon / Metrosene Plus, 100% Polyester, No. 100 red.
Bobbin thread: Amann / Mettler Seralon / Metrosene Plus, 100% Polyester, No. 100 white.
If other fabrics and/or threads are used, especially of a different quality, the stitching result may deviate from
the default pattern.
The following stitch and pattern formations must be checked in this order and according to the
respective criteria:
3.9.1 Straightstitch (default settings)
Needle-thread stitching target state
Criteria
• Does the thread-regulator spring move properly?
• Is the row of stitching straight?
• Is the stitch formation on both sides of the fabric regular?
• Do the threads interlock in the middle of the fabric?
• Is the seam free of skipped stitches?
BERNINA International AG Seestrasse 161 CH-8266 Steckborn
DRAFT – VERSION
Bobbin-thread stitching target state
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