Instruction manual

6.13 Sewing-foot stroke
The class 669 sewing machine comes (depending on the subclass)
standard equipped with two dials for adjusting the s ewing-foot stroke.
Use the dial 2 on the left to select the standard sewing-foot stroke
from1to9.
Use the dial 1 on the right to set a higher sewing-foot stroke from 1 to
9.
–
Turndial1and2(1to9):
1 = minimal sewing-foot stroke
9 = maximum sewing-foot stroke
Automatic stitch rate limit
Machines w ithout a thread trimmer
The speed is not verified on these machines.
Please observe the notices and the information found in the tables on
the next page.
Machines w ith a thread trimmer
The sewing-foot stroke and stitch count are interdependent. A
potentiometer is connected mechanically with the dial. The control unit
detects what foot-stroke has been set by means of this potentiometer
and restricts the speed of rotation accordingly.
Machines w ith electro-pneumatic rapid stroke adjustment
When processing thick sections of material or when sewing over
transversal seams, the higher sewing-foot stroke (dial 1) can be
activated while sewing by means of the k nee switch 3 (under the table
plate).
A potentiometer is used here just as in the machines with thread
trimmers.
CAUTION: Danger of breakage !
The standard s ewing-foot stroke as set by the dial 2 must not be larger
than the stroke set by the dial 1.
20
21
3