I attach a pulley to the selsyn shaft. The diameter of the pulley must be
identical to the mast diameter. Lately I've been manufacturing the
pulleys from a solid block of aluminum (expensive...). You can also
manufacture a pulley from a few inches of mast with end plates attached.
I use a small diameter flexible stainless steel cable to interconnect the
pulley and mast. The center of the wire is fastened to the pulley (I use
a hole bored thru the pulley, but you could use a screw or many other
methods) to prevent it from slipping. Wrap one full turn of wire around
the pulley, both above and below the attachment point. Then wrap one full
turn of each end of the wire around the mast. I use hose clamps to attach
the ends of the wire to the mast.
There are many more ways to skin this cat, but this has been very relaible
for me (I've used this method for over 25 years with very little
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