I guess I'll have to add my two cents on this. I fabricated a tram that
is 7 feet wide and will attach to the top of a 25 or 45 Rohn. It has
three points to hook the tram lines to and a roller for the pull line to
go over. I never got to use it, but it should work like a champ. It sure
would beat all three lines coming to a point at the top of the tower. I
got the idea for this the last time we put up a tribander and it wanted
to roll over when it got about 2/3rd's of the way up. If you have a flat
top tower it shouldn't be to much trouble to get it on the mast as long
as there is not to much of it above the top of the tower, hook the
antenna to the ginpole and let the ground crew take the load. Once it's
on the mast (loose) hoist the mast up install the rotor, you know the
rest.
I also fabricated a bracket to hold the mast while you R and R the rotor.
I made it out of a short piece of pipe that the mast will go through and
drilled three holes spaced at 120 degrees and welded three nuts to it to
put bolts in to lock the mast in place. It in turn has an angle welded to
the pipe to attach it to two legs of the tower. It has to be installed
before you hoist the mast up to the top.
Hope this will be of some help to someone.
73, Bill KB3AUG
Riverton, WV
On Fri, 3 Apr 1998 12:47:11 -0500 chapoton@smtp-gw.gdls.com (Henry G
Chapoton) writes:
> Ok, you got 2 things on me: guts and space. I quit tramming 'cuz
>I
> didn't really feel comfortable with the setup, and didn't have
>the
> clear ground space to lay out the antennas. I did do some
>smaller
> stuff on my R25.
>
> I put up my 3 el 40 (275#, 170') in pieces - Boom first, then
>tilted
> it and put the elements on. Biggest thing I trammed was a 2el
>Wilson
> 40 to 150' - to the mast (2"x1/4", unknown alloy, sold by
>Telrex).
>
> I think one of the biggest keys is what you feel comfortable
>with.
> The rigging to do a proper tram for a big beam can be substantial
>and
> it takes an experienced & disiplined ground crew. I don't want
>to see
> someone get killed tramming up to the top of a mast that's
>secured
> only by a thrust bearing!!
>
> Greg
> na8v/4
>
>
>______________________________ Reply Separator
>_________________________________
>Subject: Re: [TowerTalk] Re: Long mast, intermediate bearing
>Author: K7LXC <K7LXC@aol.com> at Internet/Unix
To: <towertalk@contesting.com>
>Date: 4/3/98 10:44 AM
>
>
>In a message dated 98-04-03 09:02:52 EST, chapoton@smtp-gw.gdls.com
>writes:
>
>> I don't think you want to hook your tram line to the mast unless
>it's
>> a real small beam on a short tower. There is a LOT of tension
>on that
>> line. Hook it to a tower leg at the top of the tower. If the
>tower is
>> guyed, remove one guy (loosen the other 2 a bit) and let the
>tram line
>> (I used 3/16 EHS for a tram line) be a temp guy. When you get
>the ant
>> up there, hang it from the tower, relocate the tram, move the
>pully up
>> on the mast and then pull the ant UP. If you do tram on the
>mast,
>> consider a couple back guys on it.
>
> While I sometimes use the 2-step method described above, you can
>use a
>proper mast to anchor the top of the tram line. With back-guying
>there's
>little or no pull on the mast and you can go as big as you want. I've
>trammed
>up full-sized HD 40M beams (250-300#) directly from the mast. It WAS a
>4130
>mast with 3/8" wall so it was industrial strength and it was
>back-guyed.
>
>Cheers, Steve K7LXC
>
>--
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>
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