[Top] [All Lists]

Erecting Long Masts

To: <>
Subject: Erecting Long Masts
From: (n4si)
Date: Wed, 18 Dec 1996 20:35:16 +0000
> Gents:
> I saw an elegant solution to how to get a 20-24 foot piece of chrome moly
> inside a tower. I do it a different way, and have had no problems up to this
> point in my strategy. I mention it as a point of comparison. 
> I always set the rotal at the bottom of the top section so about 8
> feet of the mast is inside the tower with about 12 feet out the
> top. 

> The way I get the long mast above the tower and down into the
> thrust bearing is that I use the standard size ginpole to raise a
> very long ginpole made out of 1.5 or 2" black pipe used only for
> this operation. 

(editted lots out, no point in repeating the whole message)

> The long ginpole simply has an appropriately large and heavy duty
> pully inserted in the top. 

> Using this top raising position, I have had no problem lifting the main most
> up over the top of the tower.

(more editting)

>                                 Gary     W5FI        Ex-W5VSZ
>         Now, the professional engineers may have problems with my strategy,
Well, Gary, I am not an engineer; just a semi-professional amateur 
tower erector, but your method sounds good to me. I also like to set 
my rotator at the bottom of the top section in some installations; it 
reduces the leverage of the mast for producing lateral moments on the 
rotator case. The price is in the "wasted" mast between the rotator 
and thrust bearing; i.e. wasted in the sense that no antennas can be 
mounted there.

And you are also right; the other method you mentioned was elegant. 
It has its applications, but yours is just as good.

73, Rod N4SI
    The DXer formerly known as N9AKE
         (c) 5 November, 1996

FAQ on WWW:     
Administrative requests:
Sponsored by Akorn Access, Inc & KM9P

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