[TowerTalk] Mast Raising Fixture

[Pete Smith]

K4ZA has an excellent solution to the problem of managing a tall mast while 
dropping it into an already-erected tower.  The write-up is at page 4 of 
the February 2004 PVRC Newsletter 
(http://www.pvrc.org/Newsletters/feb04.pdf), with a picture.  The words are 
below:

"Hams sometimes do slightly dangerous things, and that can include tower 
work, especially the job of raising heavy masts. I've done it myself, 
plenty of times, using a variety of methods. Having tried all these ideas, 
having listened to everyone else's solutions, I was still convinced there 
"had to be a better way." Driving through my neighborhood a while back, I 
had one such "Eureka" moment--coming up with a solution to this age-old 
problem.  This works better than anything else I've tried.  I recently had 
to install a 21-foot chrome-moly mast, working alone atop the tower. 
Installing a basketball goal (just the hoop) at the top of my 13-foot 
heavy-duty ginpole, provided a margin of control (and safety) missing from 
all previous methods I've used. The mast, lifted at just above its 
midpoint, couldn't swing or "get away" from me once inside the hoop, which 
made guiding it down, and into the tower top's thrust bearing, relatively 
easy. (No matter how big and strong the tower worker is, manuevering such a 
mast is always difficult ON THE TOWER, as there's no real mechanical 
advantage possible, nor a good way to control the heavy mast.)

Despite all the kidding from my ground crew, everyone agreed this simple 
tool made our work faster, and more importantly,
safer. I chose the basketball hoop because it was pre-made, relatively 
cheap (mine cost $20), and sturdy. I ground off the small loops, which 
normally hold the net, then drilled matching holes for U-bolts and saddles 
to allow mounting on the ginpole. The installation of long, heavy masts is 
now much easier. This simple tool will always be in my tower toolkit."

73, Pete N4ZR


At 09:01 AM 8/17/2004, Carl R. Stevenson wrote:



> > -----Original Message-----
> > From: towertalk-bounces at contesting.com
> > [mailto:towertalk-bounces at contesting.com] On Behalf Of
> > bobg at wisource.com
> > Sent: Tuesday, August 17, 2004 4:44 AM
> > To: towertalk at contesting.com
> > Subject: [TowerTalk] Mast Raising Fixture
> >
> >
> > Greetings all....
> >
> > Just put up a Rohn RTP to 80'....putting in a 24' mast....anyone have
> > plans for something to raise and lower it?
> >
> > Bob
> > W2CYK
>
>Bob,
>
>Just a suggestion for thought ... This may not work in your situation.
>
>Managing a 24' mast sticking up free above the top of the tower can be quite
>an effort/potential for an accident.
>
>How about this?  Can you get the mast *inside* the tower from down at/near
>ground level? (This may have been easier if done as the tower was being put
>up, but I gather you already have erected the tower.)
>
>The idea is to contain the mast within the tower and raise it up inside the
>tower to pass through the hole(s) in internal/top plate(s) so you don't have
>to wrestle with it "freestanding" projecting 24' above the top of the tower.
>
>Then, you could raise the mast *inside* the tower until it protrudes above
>(passing through the hole in) the rotor plate, any intermediate plate, and
>the top plate.  You could haul it up using a "rolling hitch" a few feet
>below the top of the mast.  Once you get the top end through at least one
>internal tower plate, you can use "vise-grip" or other "chain wrenches" to
>firmly grip the mast, allowing you to raise it further (ideally, you'll use
>2 or more of these tools).  This will give you something to lift with and
>should prevent the mast from falling all the way down should your grip slip.
>(Once one (or more) of these wrenches are on the mast, I'd still be inclined
>to move the "rolling hitch" down and tie it off - just in case - as you work
>the mast up to the final desired height. You'll probably have to raise the
>mast a bit more than the final position to get the rotor in place, then
>lower it to the final position.)
>
>Just some thoughts.  They may not work for you because it's not clear if you
>can get the mast inside the tower from ground level at this point.
>
>73,
>Carl - wk3c
>
>
>_______________________________________________
>
>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.
>
>_______________________________________________
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73, Pete N4ZR
The World HF Contest Station Database
was updated on August 2, 2004
2753 contest stations at
www.pvrc.org/WCSD/WCSDsearch.htm