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[TowerTalk] Rotor Shims

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Subject: [TowerTalk] Rotor Shims
From: (Pete Smith)
Date: Wed, 31 Dec 1997 13:26:02
At 09:36 PM 12/30/97 -0500, k4oj wrote:

>The rotor plate supplied by Rohn is a sheet metal item and it can be bent
>EASILY...if it is bent due to being jolted due to who knows what the rotor
>rather than being plum/level will want to force the mast to one side of the
>tapered top sleeve....this also could occur if some of the u-bolts which
>hold the plate in place have shifted...netting the same problem....
>With the rotor out of the tower, have you put a u-bolt or clamp to suspend
>the mast above the plate, and if so is it turning okay sans-rotor...if so,
>then you have verified your problem's possibilities as being shelf or
>If you are still experiencing binding wihtout the rotor in the picture then
>you have a mast problemo, fer sure.

The 'Ol Contester (TM), W9LT, taught me a neat trick for working with Rohn
25 pointy top -- he leaves the rotor shelf and everything else finger tight
until the antenna, mast and all are at the top of the tower, and then
tightens things starting with the mast-to-boom clamp and working out.  That
way (presuming that your mast is the right diameter, or properly shimmed),
all of the dimensionally sloppy connections, like the plate to leg U-bolts,
are tightened only after the precise ones are tight.  There's plenty of
clearance inside the pointy top, as long as your mast isn't bent.  If it
is, as Jim says, "problemo."

73, Pete Smith N4ZR 

"That's WEST Virginia.  Thanks and 73"

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