Adjusting Blade Tension - SunStar HC Series User Manual

6-1-2) Adjusting Blade Tension

Make sure to check and adjust the cross-tension of the movable and the fixed blades after replacement or repair.
① Checking the cross tension
Manually move the movable blade and cut the upper
and the lower threads. Check the cross-section of the
thread cut.
② Adjusting the cross tension
Adjust the cross tension using fixed blade tension
control screws (see [Fig.6-3]). Manually move the
movable blade and adjust that it crosses in parallel with
the cutting line of the fixed blade from its entry point
to its return point.
[NOTE]
Avoid excess cross-tension. It may cause the movable blade to wear out from overload at its entry or
return point.
6-1-3) ADJUSTING THE TRIMMER RETURN
SPRING
1) Function
The trimmer return spring detects if the movable blade
returns to the correct position after trimming. If the
machine operates without the blade returned to its
correct position, the needle and the blade may be
damaged. The trimmer return spring detects and stops
the machine if the blade has not returned.
2) Adjustment
① Unfasten the spring shaft screw so that the center of
the spring hole is around 2mm away from the
surface to which the screw is attached (see [Fig.6-
4]). Save the location of the spring.
② Adjust the return spring so that the surface and the
spring are around 1mm apart.
Movable blade
Fixed blade
Sensor
Spring shaft
screw
Return spring unit
Tension
control screw
[Fig.6-3]
1mm
[Fig.6-4]