SINGER W310 - Manual (Page 38)

If your machine skips stitches only on certain fabrics,
try all of the procedures on the previous page before
calling a repair-man.
Check the needle plate area, if there are scratches and
marks around the needle hole opening, your machine is
not being cleaned properly. Always remove the needle
plate and clean the feed dogs periodically. Improper and
lack of cleaning will cause an accumulation of lint which
hampers the feeding mechanism, this in turn will cause
the operator to impatiently pull or push the cloth
causing the needle to bend and strike the plate, foot or
hook, causing a slip in the timing mechanism.
Continuous striking will cause defects making it
necessary to call a serviceman.
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