I would tackle this rigging deli ma one of two ways.
A: use my HD WB0X gin pole with the 2" .250 wall pole. This giver a straight
down pull by the capstan winch.
B: I would mount a pulley on the mast above the tram line plate and make the
pull point a distance from the tower base .
Both these scenarios , you have the ability when the antenna is above the top
plate to slacken the tension on the tram line ( come along ) swinging the
antenna back to it's resting/mounting position. this negate the re rigging it
to it's mounting position
my .02
Wayne W3EA
> Date: Sat, 22 Nov 2008 20:54:09 -0800> From: n6ta@yahoo.com> To:
towertalk@contesting.com> Subject: [TowerTalk] Tramming help sought> > I won't
bore the readers with the usual retread questions. Already did the reading
etc. and lowered the old beam a month ago. This is one on how to rig the haul
line to pull up the 110 lb SteppIr yagi.> > The tram line is to be rigged about
3 feet above the top on the Rohn 45 tower which has a flat top plate. The boom
will be mounted right above the top plate. The tram line is continuous in that
it goes thru a pulley and down to a 'back stay point'. Trying to allow the
tram line some ability to move but direct most of the force down the mast to
the rotor.> > The beam will be hung from a sling that connects a pulley to the
tram line. The boom will hang about 18 inches below the tram line. A
tiller/torque arm will be attached 'behind' the boom, keeping the boom from
rotating in two axes.> The haul line is half inch polyester double b
raid and will be tied to the boom close to the CG point. The bracket that
holds the tram line above the tower top has a place for a pulley to be mounted
for the haul line, probably attached with a snap link or shackle. The question
I have is how to rig the haul line's pulley such that I can pull straight down
and not have interference with the tower's top plate. The bracket for the
pulley is about 3 inches out from the mast and the tower needs about 9 inches
clearance from the mast to go straight down without rubbing on the edge of the
top plate. I fear way too much friction if I allow this. I lowered the prior
beam this way and used the friction to advantage but do not want such issues
when pulling up the new beam.> If I rig the haul line pulley ( a CMI 2.375 inch
95% eff. rescue type) such that it is hanging out far enough to clear the top
plate, I end up pulling sideways on the mast.> > There must be a standard
practice here but I have not yet read any postings abou
t this detail. I usually just 'go for it' and keep the fingers crossed. I
have way too many PhDs in the School of Hard Knocks and prefer to not get
another....> > If I can pull the beam up as far as it can get, to the haul line
pulley, I plan to relax the tram line and let it settle the boom down where it
will rest on the top plate until I can use other means to raise it the 6 inches
to the boom to mast plate.> Willing to call to talk about it.> > Tnx in
advance.> Al> N6TA> > Yeah, I'm missing the CW test due to delay in getting
this up.> > > > _______________________________________________> > > >
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