[TowerTalk] Pointy-Top Discussion AGAIN!

[Stan Griffiths]

Hi Lee,

I think there are a couple of alternatives that you didn't mention.  Read on.

>Well, I just about shot myself in the foot this weekend.  Luckly, I think I
>missed so I have to take better aim next time.
>
>I have been working on a project to beef up my mast and put up a referbished
>TH6 on the 25G tower.  I have several pointy-top tower sections that I
>thought would take 2.00 inch OD tubing.  As I was working on the project and
>trying to find the tubing (just about ready to order from Texas Towers) I
>decided to measure that diameter of the tower.  Well, I have top 25AG1 top
>with the bushing removed.  So, the maximum mast I can stick through it is
>about 1 7/8" OD .. if anything like that exist.  So, with the top I have,
>the 2" tubing would not have worked.  So, alternatives.....
>
>1.  Go with a smaller diameter mast and at this point (it would be steel and
>not aluminum)

I really like 2" masts since they match rotators, beam mounting hardware,
and thrust bearings much better besides being stronger than smaller diameter
tubing.

>2.  Buy a new top (I really don't want to spend the $$$ unless it is a good
>deal)

I think you know the alternatives here.  You will have spend about $100 or a
little more to get a new full-sized top.

>3.  Make a top for a straight section.  (My welding skills are rusty)  I got
>a lot of friends to do something like that, but they are busy as well.  The
>other option here is to use a rotor shelf plate and mount a bearing on it.
>Then the price of the project goes way out of site (See option 2)

If you actually BUY another straight section AND a rotator plate, your are
right, that costs as much as a new top.

There is an item called a BAS25G that is a short top (about 2 feet).  It is
a flat top (like a 25AG4) with a rotator shelf welded in place about 18"
below the top plate.  The top is drilled for a thrust bearing and the
rotator plate is drilled just like a standard AS25G.  The BAS25G costs about
$95.

There is another item called a BPL25G that is a flat plate for a bearing
that goes on the top of a straight section.  This thing is about 18" high
and the top is just like the top of a 25AG4.  Price is about $72.

>Additional comments:  I have used a steel mast with this set up before and
>it seem to work.  Stayed up in a very sever ice storm.  But, I had nothing
>on the smaller mast that the TH6.  I would like to but up a two meter boomer
>for SSB/CW operation as well when I do this.  
>
>So, that is why the pointy-top tower discussion has started again.  I know
>that there has been a lot of things written about this topic, so we don't
>have to go through it again.  I got to make up my mind what I need to do
>here to be 1) safe, 2) safe, 3) safe, and 4) cost effective.

Bottom line:  I would go for a new 25AG3 if you want a pointy top or 25AG4
if you want a flat top.  Then I would offer the old used top for sale for
about $50 thereby reducing the pain of the paying for a new top.

>Comments and flames to me
>
>Lee Buller
>k0wa@southwind.net

For what it's worth . . .

Stan  w7ni@teleport.com


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