Golden wheel CS-471, Instruction Manual

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Problem Cause Corrective measures
1. Thread often breaks ① Flaw is found out at thread path, needle ○ Remove flaw by smoothing flaw with fine
or thread splits finely, point, shuttle blade point, or needle eyelet. paper file.
correct stitch cannot ② Improper finish around the recess in the ○ Replace the needle with a new one.
be formed (half-finished needle.
stitch) ③ Excessively tightened needle thread tension. ○ Adjust the needle thread tension.
④ The needle interferes with the blade point ○ Refer to "17.Adjusting the needle-to-
of the shuttle. shuttle relationship".
⑤ The timing of the needle and the shuttle is ○ Refer to "17.Adjusting the needle-to-
too early or too slow. shuttle relationship".
⑥ Due to heat generated by the needle. ○ Decrease the sewing speed of the mach
-ine. Use silicone oil.
⑦ Excessive height difference at stepped ○ Increase the amount of movement of
section. the thread take-up spring.
2. Stitches are frequently ① The needle-to-shuttle blade point clearance ○ Refer to "17.Adjusting the needle-to-
skipped is excessive. shuttle relationship".
② The timing of the needle and the shuttle is ○ Refer to "17.Adjusting the needle-to-
too early or too slow. shuttle relationship".
③ The presser bar pressure is insufficent. ○ Tighten the presser adjuster screw.
④ The distance from the upper end of the needle ○ Refer to "17.Adjusting the needle-to-
eyelet to the blade point of the shuttle is not shuttle relationship".
proper.
⑤ The needle is improperly selected. ○ Replace the needle with a one-count
lower needle.
⑥ The amount of movement of the thread take- ○ Decrease the amount of movement of
up spring is excessive. the thread take-up spring.
⑦ Overheated needle or shuttle. Thread is not ○ Use silicone oil.
pulled smoothly.
⑧ Reverse stitching is made at low speed on light ○ Wind the needle
weight material using nylon thread. thread around the
needle.
3. Improper thread tension, ① Poor finish of the thread path. ○ Smooth the surface with a fine paper
irregular stitch, excess- file or using a buff.
ive bobbin thread tension ② The bobbin slides unsmoothly. ○ Replace the bobbin or the shuttle.
③ Weak bobbin thread tension. ○ Adjust the bobbin thread tension.
④ Bobbin thread is wound too tightly. ○ Decrease the tension of the bobbin
thread winder.
⑤ Needle thread flaps.(Needle thread flaps and ○ Thread the tension
comes out of the thread tension disc due to guide bar as illustrated
excessive needle thread tension or is caught right.
in other parts.)
⑥ Too thin bobbin thread is used to combine with ○ Use silicone oil.
needle thread.
4. Poor gloss of the needle ① Excessive height difference at stepped section ○ Use silicone oil.
5. Inconsistently finished ① Needle is too thick. ○ Replace the needle with a thinner one.
seam(stitches are not Use cutting point needle
made straight but made
such as "
ﾐ
")
6. Bobbin thread tension ① The bobbin thread tension spring of the shuttle ○ Clean by removing the bobbin thread
cannot be increased has become dusty or dirty. tension spring.
7. The belt slips (Motor sto ① THe V belt is degraded. ○ When degradation is found out to the
-ppage occurs, if an elec V belt, such as wear, cracking, etc.,
-tronic-stop motor is replace with a new one.
used.) ② The V belt tension is not enouth. ○ Adjust the slack amount in the V belt
to 10mm/1kgf.
Handwhee
10mm
1kgf
Motor
ll
- 12-