MAINTENANCE
ROUTINE CHECKS
Hoists
Look for fraying of the hoists at flexion
points like the hoist pipe eye, which can
indicate that they are ready for
replacement. They should last a long time
with normal use, and if they look to be in
sound condition then there is no need to
change them.
When replacing hoists, use the bend of a
slip knot around the hoist toggles, and a
boom hitch around the spools.
Pivot point
It is not clear whether or how a severely
blunted pivot point might compromise
performance, since pressure against the
pivot is always maintained by gravity.
However, it is very easy to replace the pivot
bolt with a newly-sharpened one. Contact
Supatrac for more information.
Thrust Box Bolts
After long periods check that the bolts
which attach the arm to the thrust box are
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boom hitch
IMPORTANT: there is a correct height for
the suspended arm: the pivot point must
make contact with the thrust box on the
straight line between the two points
where the hoists meet the thrust box.
To ensure this, cut a 6cm by 1cm rectangle
from the corner of a straight-edged piece of
paper, insert it between the hoists and the
thrust box and raise the headshell so that
the paper’s straight edge sits on the points
where the hoists meet the thrust box. The
pivot contact should occur at or just below
the paper’s edge.
Once the correct height is set, lean can be
adjusted by shortening and lengthening the
two hoists in equal and opposite measure so
that the pivot contact remains on the line
between the suspension points. Always
check that the pivot contact lies on this line
after adjustments by resettling the
suspension and applying the paper test
again. A period of incremental adjustments
to suspension height may help to establish
optimal performance.
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pivot bolt
straight edge
paper
hoists
thrust box
