What you are describing is not nearly as difficult as most expect with those
dimensions. However it does depend on how heavy that 24' of mast is going
to be.
> OK, so lets say I've got my new, super HD, 70', freestanding, Trylon or AN
> Wireless tower up in place. Now I've got to get that 24' Chrom-Moly mast
> up there and through the thrust bearing somehow. How the heck do you do
> that (no cranes allowed, it looks like I'm going to have to stick build
> the
> tower)?
The easiest is to have a gin pile that extends just over 12 feet above the
top of the tower. You don't have to hook on the end of the pole. That
means you need a gin pole only slightly taller than what is normally needed
to add 10' sections. My regular Gin pole already extends that far and
requires no extra effort.
I've even raised "top heavy" masts by putting a pipe extension on the side
of the tower and a loop at the top of it. I then raised the mast up through
the loop to keep it from tipping over. This is not a method to be taken
lightly or without due consideration before starting the work. Every thing
needs to be right the first time!
In my case I have over 40 feet of mast. I raised two 24 foot sections of 1
1/2" and then lowered them down through the tower to a convenient height
where I welded them together. I then raised a 24' section of 2" and lowered
it into the tower so the top was sticking up above the top thrust bearing by
about 2' and tightened the bolts in the thrust bearing to hold the mast. At
this point I switched from using the Gin Pole to a big come along to raise
the mast which was now too heavy for the Gin Pole.
The two sections of 1 1/2", now welded together were pulled up through the
2". The top UHF/VHF cross boom and arrays were attached and the 1 1/2" was
raised to a bit over 12' above the end of the 2". Then the 7L 6-meter beam
was attached, the 2" and the 1 1/2" were pinned together and raised another
15' where the tribander was atached. The whole works was raised to put the
tribander about 2' above the top of the tower and both the top and bottom
thrust bearings were tightened. Then the rotator was installed.
It's time consuming and you have to have your steps planned out ahead of
time. I did most of the work alone with the exception of raising the
antennas to the top of the tower where I installed them. I did all the
tower work alone with the only help being on the rope to the gin pole. I
even did the rope work for most of the masting.
> The antennas I can tram up on temporary guy wires, but even if I
I did not find it necessary to tram up any antennas. I simply went up the
tower with each one as it was raised using the rope through the gin pole.
When I reached a set of guy lines I rotated the antenna around the guy atach
point. It turned out to be relatively simple.
http://www.rogerhalstead.com/ham_files/TOWER24.HTM and
http://www.rogerhalstead.com/ham_files/TOWER23.HTM show the process. In my
case it was complicated by the guy lines from the old tower running within
10' of the new tower which made things... interesting. In the last link you
can see Bill, N8FUZ handeling the rope to the gin pole.
There is a close up of the gin pole, but unfortunately it's in the middle of
the following page and there are a lot of photos on that page.
http://www.rogerhalstead.com/ham_files/tower.htm
73 and good luck.
Roger Halstead (K8RI and ARRL 40 year Life Member)
N833R - World's oldest Debonair CD-2
www.rogerhalstead.com
> could do that with the mast I've still got to stand it up to get it
> through
> the center of the tower. Big gin pole? Seems like you'd need a gin pole
> to
> raise a gin pole big enough to handle one of those monster masts.
> Helocopter? Maybe... gee, might as well have them pick up the tower as
> well, but how much does that cost? Anyone have experience with that and
> can
> give me a ballpark number? It's gotta be big bucks, and doing it over a
> residential neighborhood? Maybe not even possible. So, how the heck do
> you
> do that? Build the tower around the mast and pull it straight up the
> middle? Any other suggestions?
> Thanks & 73 - JC, k0hps@amsat.org
>
>
>
> _______________________________________________
>
> See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless
> Weather Stations", and lot's more. Call Toll Free, 1-800-333-9041 with
> any questions and ask for Sherman, W2FLA.
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
_______________________________________________
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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