14
mECHANICAL ADJUSTmENT
CLEARANCE BETWEEN NEEDLE AND HOOk
(ADJUSTmENT mETHOD NO.2)
TO CHECk:
Use this adjustment method NO. 2 if the clearance cannot be adjusted by the method NO.1.
The clearance between the needle and shuttle race should be –0.05 to +0.10 mm.
ADJUSTmENT PROCEDURE:
1. Set the pattern selector dial at " ".
2. Remove the rear cover (See page 7).
3. Loosen the setscrew (A) on the lower shaft bushing and slide the gear about 0.5 mm to the right to create
some slack between the gears.
4. Lower the needle and loosen the two shuttle race setscrews (B).
Move the shuttle race unit axially either forward or backward to adjust the clearance between the needle and
the shuttle race in the range of –0.05 to +0.10 mm.
5. Set the pattern select dial at " ", turn the handwheel to check if the clearance between the needle and inner
edges of the shuttle race spring at the left and right needle drops are equal.
If not, adjust by turning the shuttle race unit.
6. Tighten the two shuttle race setscrews (B).
7. Loosen the setscrew on the lower shaft bushing and slide the gear back to the original position while adjusting
the backlash.
8. Tighten screw (A) firmly.
9. Attach the rear cover.
NOTE: The rotary play of the tip of the shuttle driver should be less than 0.3 mm and the
lower shaft should turn smoothly.
After the adjustment, check the hook timing.
–0.05 to +0.10 mm
Clearance should be equal
Shuttle race
setscrews (B) (2 pcs.)
Lower shaft bushing (front)
Needle
Shuttle race spring
Setscrew (A)
