Towertalk
[Top] [All Lists]

[TowerTalk] Pointy Top / Mast Binding - Tips?

To: <towertalk@contesting.com>
Subject: [TowerTalk] Pointy Top / Mast Binding - Tips?
From: w7ni@easystreet.com (Stan or Patricia Griffiths)
Date: Fri, 20 Jul 2001 06:31:19 -0700


Bill Coleman wrote:

> On 7/18/01 2:34 PM, Stan or Patricia Griffiths at w7ni@easystreet.com
> wrote:
>
> >
> >Does the mast actually bind in the top of the 25AG3 itself alone or does
> >it tend to bind
> >only when inserted into the rotator?
>
> Well, I have the mast inserted into the AG3 in the horizontal position. I
> was just doing a test fit, and I don't have 15' ceilings in my basement
> to test it vertically.

Actually, you can do this test horizontally, like you are doing, just fine.

> > I have never known a 2 inch mast to
> >have a tight
> >fit in a 25AG3 unless it was due to too thick a galvanized coating on the
> >mast . . . not
> >a problem with an aluminum mast.
>
> It's not tight, it just seems to take a bit of effort to rotate.

Is there any chance that the 2 inch alumnum mast is really a little larger than
2 inches?  Or could it be slightly warped?

> I'll have to move it outside vertically, rig up the rotator and try it
> out a few times.

It ought to turn real easy without the rotator installed.  If it doesn't,
things can only get worse with the rotator in there.

> >If the snug fit occurs when it is put in the rotator, I would suspect that
> >the rotator
> >is not properly shimmed to center the mast or that the axis of the rotator
> >is not
> >parallel with the axis of the mast.  I can suggest ways to fix both of
> >these problems.
>
> One item I have to figure out is how to line up the rotator shelf so the
> rotator axis is parallel to the axis of the top.  Suggestions there would
> be helpful.

Early Ham-m rotators were made for 2 1/16" OD masts and binding occurred if you
did not shim them 1/32" from both points where the mast contacts bell casting.
I am not sure, but I don't think this was a problem with later Ham-Series
rotators . . .

> I was planning to leave the shelf loose, then put the rotator in place
> and have the mast position everything properly, then tighten the shelf.

That is the right idea.  Tighten rotator ubolts first, rotator to plate bolts
second, and plate to tower leg ubolts last.

> >I have never heard of anyone needing to lubricate a 25AG3.
>
> For my own piece of mind, I may coat the insides with LPS 2.

It can't hurt.

> Bill Coleman, AA4LR, PP-ASEL        Mail: aa4lr@arrl.net
> Quote: "Not within a thousand years will man ever fly!"
>             -- Wilbur Wright, 1901

Hope you get this worked out.  I simply never needed any of the complex cures I
have read about here on Towertalk . . .

Stan
w7ni@easystreet.com




List Sponsor: Are you thinking about installing a tower this summer? Call us
for information on our fabulous Trylon Titan self-supporting towers - up to
96-feet for less than $2000! at 888-833-3104 <A 
HREF="http://www.ChampionRadio.com";>
www.ChampionRadio.com</A>

-----
FAQ on WWW:               http://www.contesting.com/FAQ/towertalk
Submissions:              towertalk@contesting.com
Administrative requests:  towertalk-REQUEST@contesting.com
Problems:                 owner-towertalk@contesting.com


<Prev in Thread] Current Thread [Next in Thread>