Hi Justin,
I didn't have mine at roof level but I do have a little "insight" when it
comes to 25G foldover towers.
At what height is the ROOF LEVEL?? I assume this is a flat roof ???
Are you doing it against the building because there is no room behind or on
the sides of the building?
WARNING ! The voice of experience says that "winches" can be dangerous
to your health" !!!
The whole idea of a fold over tower is to allow one to work on their
antennas ON THE GROUND and NOT have to climb the tower.
If you prefer to work on the roof. I SAY " GO FOR IT".
In the 10 years I had mine, I only had to tilt it over a few times. It was
great for rotor maintenance, antenna maintenance and switching out
antennas. You probably know that the rohn 25g foldover came as a standard 40
foot tower? By inserting one straight section below the hinge and one above
the hinge you could tilt over 60 feet. That was in my younger days so it
would be even more appealing today. Sure beats climbing. Some brave souls
even added TWO sections below the hinge and TWO above the hinge. Actually
I would probably have been dumb enough to do it myself but I didn't have
room enough on my small lot to get the guy wires out far enough to go far
enough to guy 80 feet of tower.
25G tower (when built to rohn specs) uses a 4 wire guy system below the
hinge & 3 guys at the top. There is quite a lot of weight/moment
consideration when the the antenna is cranked about 2/3 of the way up. You
may have to do some reinforcing to the building where you bracket the legs
to the building. Initially that tower performed well. Once totally
vertical, the counterweight/boom is pinned and extra bolts go into the tilt
over section . That means you still have to climb to 40 feet to take the
bolts out to crank it down up and then go back up and put the bolts back in
when done but at least no antenna work had to be done on the tower. I had
a TH-6 with an 11EL 2m beam 10 feet above the TH-6 on a heavy duty mast..
I no longer have this tower as a "tilt over" because we had a winch lock
failure when the tower was being cranked vertical. when It got up 3/4 of
the way , the winch brake "released" on its own allowing the cable to
unreel unimpeded by friction and in about 1.2 seconds that whole top
section "swung" back to the ground pulverizing the antenna, breaking the
welds at the hinges and bent the counter weight boom section. Two other
sections of 25G were bent and it absoluely "PULVERIZED" the antennas and
mast.
Luckily no one was hurt
I always thought the winch cable was the weak point so I detached the winch
and kept it inside to keep it from rusting. It only took about 10 minutes
to re install the winch when the tower needed to be tilted. As it turns out
the tower itself was rugged but the "winch brake" and not the cable was the
weak point Take care when winching it vertical.
press on regardless
73
Chet N6ZO
----- Original Message -----
From: "Justin Wilson" <j2sw@mtin.net>
To: <towertalk@contesting.com>
Sent: Monday, February 20, 2006 12:42 PM
Subject: [TowerTalk] Foldover at roof level?
> Anyone ever done a light folder over (rohn 20-25) at roof level? I
> have a tower going up that is bracketed to the wall of an office building.
> I would like to have it fold over right above the roofline so I could fold
> the tower over onto the roof.
>
> Bad idea? Good idea?
>
> Thanks,
> Justin
>
> --
> Justin S. Wilson <j2sw@mtin.net>
> Web: http://www.mtin.net
> Web: http://www.jwilson.ws
> _______________________________________________
>
>
>
> _______________________________________________
> TowerTalk mailing list
> TowerTalk@contesting.com
> http://lists.contesting.com/mailman/listinfo/towertalk
>
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