It's only a problem if you choose to view it that way :-)
Yeah, my PC under-table base mount for the motor isn't silky-smooth either.
It's probably just as raggedy and bumpy as yours -- and I've been
using/adjusting mine nearly every day for over two years now. (Not much
need to worry about wear!) Slather on a good thick gob of JPW in the
grooves and keep the motor and mount well waxed. That will help.
Seriously, it seems like it's a heck of a problem but it isn't -- you'll get
used to it (but hey, one can get used to getting lynched after the first few
times). I really don't have any problem setting the router bit height to
exactly where I need it to be in spite of that gravely spiral adjustment.
BTW, I recently got a Rockler router table & fence etc. and find it to be
highly over-rated and particularly _not_
a good "bang for buck" value.
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