[TowerTalk] Fixing cable on a Wilson 77ft tube crankup

[Robert W5AJ]

Here's the story:
HW WE RECABLED A WILSON 77FT TUBE TOWER.
The tower here is a Wilson 77ft crankup/tilt over tube type.  These are
some of the
things we did to recable the tower.   One of the guiding rails was also
repaired
which we've had more than our share of experience working on.

TOOLS:
1.  Helper (My 13yr old son kd5aau, WA5ZVE came over for the heavy tube).
2.  Chain sets with hooks.
3.  Hardware store with properly equipped necopress tool & cable.
4.  1981 Chevy Blazer in 4 wheel drive low.
5.  Various wrenches & screwdrivers.
6.  Lots of spray lube
7.  One adjustable height baby chair.

Story:
1.  Cranked down the tower & locked the base so they tubes would not
rotate.
2.  Tilt over and remove all antenna.  Store antenna in safe place.
(remember to attach
lowering cable before opening up top support.)
3.  Place tube horizontal and support under far end.  I used a strong
support and
off loaded off some of the weight onto the support.  My support could hold
more than 
the tower.  Cables connect to the bottom of the tubes OR string under them.
 The tubes
must come out to recable.
4.  Next we removed the top retainer ring which is located on the top of
the 
next larger size tube.  Take a small chain and hook it on tube top that the
retaining ring
was just removed from and wrap it back on other tube supports so larger
tubes can not
slide out.  
Slide out the smallest tube, insure the cable follows out or it will bind. 

We placed the baby chair as a support on the end of the tube.    
The tube is not self supporting while being pulled out and needs to be
supported.  
Once out, place the tube to the side.  If it binds see Blazer method below.
5.  I didn't mention removing the mast out of the top tube.  IF yours is
like mine,
the mast is now a permanent attachment and can not be removed.
6.  Now remove the next retainer ring and prepare to remove the next tube. 
If stuck
use Blazer with chains to pull the tube.  IF your cable is broken pull,
push twist until
you get some cable remains to come out.  Grab onto the cable with chain &
blazer and pull.
Support the end as before.   The pull with Blazer is gentle - idle only, no
gas.  Well maybe
a little throttle at times.
7.  Ditto the next tube, except this is where ZVE came over and helped with
handling the
tube when it was pulled and put on the ground.
8.  Paint anything you need to now!   I painted strips so I could tell if I
was on the stops
or a homemade "where is full up?" indicator.
9.  Replace cables.  Each cable attaches at the bottom of each tube except
for the last tube
out.  The bottom tube uses a long cable that has only one necofitting.  The
other end connects to
the motor drive lift or hand crank.  When I checked out the necopress
fittings I found
one hardware store had the necopress fittings & correct tool.  Another
place had the instructions.
Depending on your size of cable - sets the number of presses you must make
with the tool.
Mine had 3/16" cable.  The book said 4 presses but Wilson had only done 3 &
we only fit 3.  
It might be possible to get 4 if you start with that goal in mind.  I think
1/4" and larger
you should check out before you start how to handle the necopress fittings.
10.   My top tube had a retainer ring on it that could not be removed. 
Wilson had welded on
the bottom plate and the top holder for the mast was welded on.  This meant
to replace this
cable I had to bring the necopress fitting tool to the tower.  You need to
have a friend at
the hardware store for this trick or rent one.
11.  Since Wilson is out of business it meant that the cable length was
best guess.  I got
mine perhaps 2" too long.   Best I can tell it will just be a little
shorter when cranked up.
12.  Next I repaired the short rail piece that was broken off.  With the
top retainer
off it was clear to see that the holes had been drilled on the seam of the
tube.  
I couldn't change this without redrilling the entire length and redoing all
the rail on that tube.  
This time I went to my favorite Hardware store (Kemah Hardware) and bought
STEEL rivets that where
1/2" long.   I'm not sure with rivet being in the seam if it will ever
correctly hold, but
AL rivets are not strong enough for this service.  This short rail keeps
the tower from twisting
when the tower is cranked down.  The seam makes the 1/2" long rivet almost
too short.
13.  After reattaching cable at bottom of tube, I used some duct tape to
secure cable to tube
about 6 feet up to help reduce binding.  IF cable & tube bind up, it
requires Blazer to work
back out and try again.  Reinstall tubes, retaining caps, etc.   Pretty
good idea of
what's going on at this point.   Insure slack is out of that bottom tube
cable before you get
in other tubes and that it's fully installed into the base tube.  
If you must try to remove a tube due to binding, chain in the good tubes so
they won't pull out.  Reattach cables to retaining caps.  Insure everything
is tight.
14.  Reinstall antenna and lift back into place.  crankup.  remove securing
bolt for twisting.
DONE!   W5AJ
Disclaimer:  This is NOT an instruction set, just a story of how we did it.
I have no interest or stock in the Wilson Tower company wherever they
maybe.





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