Uneven Seams (2); Uneven Seams (3) - Brother KE-430HX Service Manual

13-4 . Uneven seams (2) ...... Thread jamming
Items with a "*" in the "Page" column should only be handled by a qualified technician.
Cause
Thread take-up
spring
Shuttle race thread
guide
Hook
13-5 . Uneven seams (3) ...... Upper thread mis-winding
Items with a "*" in the "Page" column should only be handled by a qualified technician.
Cause
Upper thread
Thread take-up
spring
Needle
Check
Thread take-up spring
tension
Shuttle race thread guide
position
Needle bar lift amount
Check
Upper thread tension
Upper thread trailing length is
long or uneven.
Tension at the beginning of
sewing
Thread take-up spring
tension
Button position
(BE-438HX/HS)
KE-430HX/KE-430HS, BE-438HX/BE-438HS
Remedy
・ If the upper thread trailing length varies considerably,
increase the thread take-up spring tension.
・ If the upper thread trailing length is short, decrease
the thread take-up spring tension.
・ If the thread take-up spring operation is unstable,
increase the thread take-up tension, and also
increase the stroke.
Adjust the shuttle race thread guide position.
The needle groove is aligned
with the center of the needle.
Adjust the needle bar lift amount.
Adjust the needle and hook timing.
Remedy
Decrease upper thread tension to such a degree that it
does not influence stitch quality.
Turn the sub-tension nut to adjust the tension.
* When using the thread nipper device, adjust the
upper thread trailing length to 35 - 40 mm.
Change the value of memory switch No. 551 to change
the upper thread tension releasing stitch count at the
sewing start.
* Although the upper thread mis-winding will decrease,
the upper thread pulling out will increase if the upper
thread tension is not released at the sewing start.
・ If the upper thread trailing length varies considerably,
increase the thread take-up spring tension.
・ If the upper thread trailing length is short, decrease
the thread take-up spring tension.
・ If the thread take-up spring operation is unstable,
increase the thread take-up tension, and also
increase the stroke.
Check that the needle is not touching the button.
13. TROUBLESHOOTING
Page
134*
137*
4077B
136*
Page
Instruction
manual
Instruction
manual
21
134*
141
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