Singer H74 Instruction Manual page 22

The presser foot lifter raises and lowers the
presser foot.
When sewing several layers or thick fabrics,
the presser foot can be raised a second stage
for easy positioning of the work.
.... i
/ The presser foot pressure of the machine has
been pre-set and requires no particular
readjustment according to the type of fabric
(light-or-heavy weight).
However, if you need to adjust the presser
foot pressure, turn the presser adjusting
screw with a coin.
For sewing very heavy fabric, loosen the
pressure by turning the screw counter
clockwise, and for thin fabric, tighten by
turning it clockwise.
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