HQ Infinity Service Manual
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At the top of the presser bar, the small set screw on
the clamp goes into the upper (rear) shaft groove
to establish the proper positioning relationship
between the upper (rear) and lower (front) shafts.
This ensures proper shaft engagement into the
clamp so it will hold. It also prevents the clamp
from falling down during adjustment to where it
cannot be reached for retightening.
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IMPORTANT
: The small screw must be tightened only enough to engage into the slot in the upper
shaft. It must not be fully tightened until after the clamp screw has been tightened, or it can
prevent the clamp from being properly tightened on the two bars.
NOTE
: A few machines were built with a smaller screw that uses a 0.7mm tool. Later, a larger
screw was used that requires a 0.05"/1.27mm tool.
The upper (rear) bar in its lowest position should ideally be even with, not above or below, the lower
head frame bushing bottom edge.
The collar on the upper (rear) bar is eccentric for
proper clearance and the screw should be straight
out to put the smallest part of the collar next to the
take-up lever. When it is tightened with a 2.5mm
hex tool, push down on it to put a little pressure on
the felt piece. Photos are shown with the cover off
for clarification but can be adjusted with the front
cover on.
Small set screw