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Trouble
Cause (1)
Cause (2)
Check and corrective measures
From the previous page
5-4) The needle is defective.
4-A) The needle is bent.
Replace the needle.
4-B)
The needle has a flaw.
Replace the needle.
4-C) The needle tip is blunt.
Replace the needle.
4-D) The needle mounting direction
is inappropriate.
Mount the needle appropriately. Defective sew-
ing is likely to occur when the needle recess
portion faces frontward.
4-E) The needle is too thin or thick
for the thread to be used.
Replace the needle.
4-F) The needle tip is too sharp.
Use a ballpoint needle.
5-5) The matters related to the
hook are inappropriate.
5-A) The thread path of the hook has
a flaw.
Replace the needle.
5-B) The blade top of the hook is
blunt or worn.
Sharpen the blade top of the hook or replace
the needle.
5-C) The clearance between the
hook and inner hook presser is
too small.
Increase the clearance to smooth the thread
passing.
5-D)
Hook oil is insufficient.
Adjust the hook oil volume to the appropriate
level.
5-E) The thread path of the hook has
a flaw.
Replace the needle.
