this ties in with what I have been preaching for years - whenever possible
let the ground crew be the ones to supply the muscle...
last tower we put (55G) we had a pro stack the sections - he had a hitch on
his x-long gin pole near the middle - he ran a rope through a pulley from
the mid point of his gin pole and the pull rope ran down to the ground - on
the ground we supplied to boost and he just had to steer it into
position....was much faster/easier/safer for the guy on the tower - fer
sure...
the guy on the tower should pre-evaluate a project as to what he is going to
need at each phase of the job and prep for contingencies when deciding what
to bring up the tower...carefully thinking through the project makes for
shorter times on the tower - and with the help of a competent ground crew
things can go very fast since the slowest thing you tend to do on the tower
is muscular things - not wanting to move an antenna or gin pole to quickly
for fear of getting away from you!
another tie in to this - I have found the counter weighting the loads as the
go up is another way to speed things for the guy on top - lets say you gin
pole will not extend quite far enough for you to get that mast above the top
plate...since you are using a ground crew have them haul up the mast with a
counter weight on the lower part of the mast - this moves the balance point
closer to the bottom of the mast allowing you to use a pick point closer to
the bottom of the mast and farther form the top - net result you can raise
it higher thanks to your friends on the ground - when you send back the
counter weight just be cautious after all you want them to keep doing the
lifting, right?
Jim, K4OJ
----- Original Message -----
From: "Stan & Patricia Griffiths" <w7ni@easystreet.com>
To: "Towertalk" <towertalk@contesting.com>; <n4kg@juno.com>
Sent: Wednesday, July 10, 2002 6:51 PM
Subject: Re: [Towertalk] mast
> Another thing to consider is using a block and tackle with lots of rope to
> reduce the load on the gin pole and make it easier for the ground crew to
> hoist that heavy mast. If you are using a Rohn gin pole, they are
> recommended for 25 or 45 sections only and a 45 section weighs only 70
> pounds.
>
> Stan
> w7ni@easystreet.com
>
> ----- Original Message -----
> From: <n4kg@juno.com>
> To: <TOWERTALK@CONTESTING.COM>; <stetrekve@yahoo.com>
> Sent: Monday, July 08, 2002 5:22 AM
> Subject: Re: [Towertalk] mast
>
>
> > The SCARIEST thing I have ever done on a tower
> > was to install a 20+ ft 100 lb. mast in my 130 ft tower.
> >
> > If your tower is NOT already in place, it is MUCH better
> > to place the mast inside the bottom 2 or 3 sections and
> > then proceed to finish the tower. ONE way to do that is
> > to temporarily strap 4 sections of tower next to the
> > permanent tower and use that to raise and insert the mast.
> >
> > If the tower is already in place, the SAFEST solution is
> > to hire a crane. A LONGER than normal (say 12 - 14 ft)
> > GIN Pole could also be used IF you really know what
> > you are doing and have a GOOD crew and equipment.
> >
> > I would give serious consideration to the CRANE solution.
> > You could then use the crane to also raise the antennas,
> > either pre-installed on the mast or one at a time.
> >
> > Tom N4KG
> >
> > On Sun, 7 Jul 2002 21:51:01 -0700 (PDT) steve sala <stetrekve@yahoo.com>
> > writes:
> > > I have a 23.5 foot steel mast that weighs 98 lbs. It
> > > is 0.2" wall and 2" OD. I want to put in my 85 foot
> > > Rohn 25 tower and put a Force 12 5BA (10.8 sq ft, 72
> > > lb) at the 86 foot level, a M2 6 meter beam (6M7JHV,
> > > 2.5 sq ft, 17 lb)at 94 feet and a M2 2 meter beam
> > > (2M9SSB,1.25 sq ft, 1.2 sq ft) at 103 feet. Does the
> > > mast present a problem with its weight? The tower is
> > > guyed at three levels for 90 mph per the Rohm book.
> > >
> > > Steve K7AWB
>
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