K9OFG asks:
"So, how about locating the open side of the rotor bell such that the
set-bolt is opposite, and loosening the u-bolts a bit at a time while
tightening the set bolt till the set bolt has the mast clamped solidly?
Seems that would avoid any centering problem"
.......close, but no cigar, as they say here in Tampa........
Especially if you are using a Telex ham series rotor which has built into
its design, the anticipation of a 2 1/16" (did I get that right, Barry)
diameter mast. (As opposed to the rotors which use split brackets on the
top like Create, etc.)
ONLY if the mast is this diameter will the mast NOT rotate eccentrically
around the center of the rotor housing....in other words...almost never do
you exactly have this...especially if you use plumbing pipe (a definite no
no) instead of 2" OD mast.
Why? Since one side which is holding the mast is fixed (the bell housing)
its position relative to the center rotational axis of the rotor is
constant.....it is FIXED, the u-bolts only serve to pull the must up
against it.......and in reality, it does NOT center the mast unless the
mast is the 2 1/16 OD, ever!
Unfortunately this was learned from the ole school of hard knocks
/////REALITY//////
Draw yourself a sketch as viewed from above, the housing bell always is in
the same position relative to the axis of rotation....taking it to the
extreme, if you were to put in shall we say a 1" OD pipe it would align way
too far into the vee of the bell.....if you used a 3" pipe it would not go
far enough into the vee.......either way the end result is a mast which
rotates eccentrically.
NOW, couple that with the bolt coming in FROM ONE SIDE ONLY on your pointy
top (part your hair to the side, to make it less noticeable) and at one
point of the rotor's rotational cycle you are at the "low spot" where the
mast is the furthest in one direction off center...lets call it
North....you then tighten your pointy top bolt.
When the rotor turns 180 degrees to the South, the mast will still continue
to be rotating eccentrically and now it is eccentric favoring the "high
spot" - and your pointy top bolt is causing all kinds of havoc at rotor
level because the mast is being forced sideways by the bolt, putting
leverage on the rotor bell......
Not a pretty sight......
QSL?
73,
Jim, K4OJ
k4oj@ij.net
Less than 2 months until Sweepstakes CW, make sure you work me so you will
not miss the elusive South Floirda multiplier!
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