This works quite well. A friend has a cable/shackle and pulley attached
underneath the top plate running down to a hand winch mounted on two legs 3
feet up from the base. The mast has a hook welded on about a foot above the
rotator. Makes antenna installation/removal a snap.
73, Keith NM5G
-----Original Message-----
From: towertalk-bounces@contesting.com
[mailto:towertalk-bounces@contesting.com] On Behalf Of David Robbins K1TTT
Sent: Tuesday, June 07, 2005 4:30 PM
To: towertalk@contesting.com
Subject: Re: [TowerTalk] installing monster masts in towers
Actually... the knot/shackle or a through-bolt doesn't matter at the bottom
of the mast. Only the top of the mast has to fit through the bearing(s) or
top tube. Raise the mast up to near its final position and then put the
rotor shelf under it and you never have to worry about the size of the
bottom hardware. The way I did a 20' mast on rohn 45 I only pulled it up
until just the top was through the tube, then clamped it and removed the gin
pole rope. The first antenna was clamped on and then the mast was raised
from there by lifting with a come-a-long hooked to the bottom of the mast
inside the tower.... jack it up 5', add another antenna, jack it up again,
add another one... then put in rotor plate and rotor under the mast.
David Robbins K1TTT
e-mail: mailto:k1ttt@arrl.net
web: http://www.k1ttt.net
AR-Cluster node: 145.69MHz or telnet://dxc.k1ttt.net
> -----Original Message-----
> From: towertalk-bounces@contesting.com [mailto:towertalk-
> bounces@contesting.com] On Behalf Of ersmar@comcast.net
> Sent: Tuesday, June 07, 2005 20:44
> To: JC Smith; towertalk@contesting.com
> Subject: Re: [TowerTalk] installing monster masts in towers
>
> JC et al:
>
> Sorry. Only the KNOT should fit into the bottom of the CM mast.
> The shackle should be large enough to keep the knot from sliding
> farther inside the mast, but small enough to fit through the holes in
> the shelves/bearings. Due to some incomplete editing of my original
> posting, it appeared as though the knot AND shackle should fit into the
mast.
> Obviously a bad thing.
>
> 73 de
> Gene Smar AD3F
>
>
>
> > JC:
> >
> > You've got it: Build the Trylon or ANW tower AROUND the CM mast.
> > Seriously. It's what I did, although a bit belatedly. (See below.)
> >
> > After you have the first/bottom section built and concreted
> > into
> place
> > (allow for a week or so of curing), remove all the braces on one
> > side of
> the
> > lone tower section. Then you can lean the CM mast against the
> > inside of
> the
> > tower and reassemble the braces. Once the CM is inside the base,
> > you
> can
> > continue having fun with your erector set in the back yard and
> > finish
> the
> > construction.
> >
> > After the tower is completed, you'll need a ginpole at the top.
> Feed the
> > haul line from the ginpole down through the bearing(s) and the
> > rotator
> plates
> > and thread it throught the CM mast from the top. Securely tie the
> > end
> of the
> > haul rope onto a shackle that will rest against the bottom of the
> > mast
> while
> > hauling it up through the two or three shelves. This means that the
> knot and
> > shackle must be small enough to fit into the mast and the shackle
> > small
> enough
> > to slide through the openings in the plates and bearings.
> >
> > Once the mast emerges from atop the tower, lock it temporarily
> > into
> place
> > with something - I used two pair of back-to-back muffler clamps
> > around
> the mast
> > and resting on the top and middle bearings. With the clamps
> > securely
> holding
> > the mast in place, remove the haul rope and use a come-along to lift
> > the
> mast,
> > plus antennas, into their final positions.
> >
> > I didn't run across this idea (courtesy of N3RR) until the
> > tower
> was
> > completely built. I had the delicate task of leaning the CM against
> > the
> bottom
> > section of the finished tower and removing one brace at a time from
> > the
> side of
> > three lowest sections as I allowed the mast to tip backwards into
> > the
> center of
> > the tower. I removed one brace at a time, then replaced it, to
> > ensure I
> didn't
> > remove too much of the structural components of the finished tower
> > at a
> time.
> >
> > CAREFUL: If you completely build the tower first as I did, be
> > sure
> the CM
> > mast is securely tied onto the tower while you are letting it slide
> > into position inside the tower. A better (and safer) approach would
> > be to
> encase the
> > CM mast inside the tower after the first section has been concreted.
> >
> > 73 de
> > Gene Smar AD3F
> >
> >
> >
> > > 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 antennas I can tram up on temporary guy wires, but
> > > even
> if I
> > > 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.
> >
> > _______________________________________________
> > 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.
>
> _______________________________________________
> 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.
_______________________________________________
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.
_______________________________________________
TowerTalk mailing list
TowerTalk@contesting.com
http://lists.contesting.com/mailman/listinfo/towertalk
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