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[TowerTalk] tramming vs. "riding the rope"

To: towertalk@contesting.com
Subject: [TowerTalk] tramming vs. "riding the rope"
From: Randall K Martin <rkmassoc@comcast.net>
Date: Wed, 09 Sep 2009 14:28:42 -0600
List-post: <towertalk@contesting.com">mailto:towertalk@contesting.com>
Gregg,

I am one of those that would say tramming is easier.  Way back with my 
first tower, I did the two rope method to raise a 4 element cushcraft 
20M to the top of a 70 foot tower and it was a real pain.  Over the 
years, I've refined my methods.

I've done quite a bit of work here this summer and have trammed at least 
a dozen antennas up and down the towers, the largest ones being KT36XA's 
and an old KLM 15 meter monbander on a 36 ft x 3 inch boom.  I have been 
able to successfully handle all of these with no help whatsoever, except 
that I did need help from my son for about 10 minutes handling a tag 
line on the KT36XA that went up to the 90 foot level.  I have clearance 
problems with one guy wire and needed someone on the ground to help get 
the antenna up and over that one guy.  My tram line is 1/4 inch diameter 
aircraft control cable.  Most of the time, I use a lawn tractor to 
carefully pull the larger antennas up the tram line.  If the tram line 
angle isn't too steep, it is pretty easy to pull even a KT36XA up 
without any help.

I never attach the tram more than three feet up the mast, and usually 
less than that.  For the heavier antennas, I run the tram line up and 
over a heavy duty pulley attached to the mast and down to the opposite 
side of the tower.  That way, I have a backstay and there is very little 
horizontal stress on the mast.  When the antenna gets to the tower, it 
ends up a few feet below the top of the tower.  All I do is release the 
tension on the tram line at that point, climb the tower, attach a come 
along to the antenna, and ratchet the thing up the rest of the way. 
This has all been discussed in previous threads.

To prevent "turtling" of the antenna, I fabricated a couple quick and 
dirty brackets made out of a 3 inch u-bolt, a piece of angle iron, and 
an eight inch long piece of 1-1/4 inch square aluminum.  The u-bolt 
attaches to the angle iron, and the aluminum sticks out from the angle 
iron.  I drilled small holes through the other end of the aluminum. 
Once I have the antenna balanced with my slings, I simply mount these 
brackets on the boom a few inches inside the sling attachment, with the 
aluminum pieces pointing straight up, where the tops of the aluminum 
extend just past the sling.  I then run some 12 gauge copper wire 
through the holes in the aluminum and around the sling.  This keeps even 
the top-heavy KLM yagis from turning over.  You could probably use steel 
for both parts of the bracket and then attach your sling directly to the 
top end of each bracket but I just happened to have the aluminum on 
hand.  If you want, I can send you a photo of one of the brackets.

Finally, what I think is the most important point is to use a tiller 
bar.  Lots of info on that in past threads, but all it is is a short 2-3 
foot long piece of angle iron with mounting holes for a 3 inch u-bolt at 
one end and a hole for a carribiner at the other end.  The tiller 
attaches at the center of the boom and the pull rope attaches to the 
tiller.  By adjusting the angle of attack with the tiller, you can 
closely control the attitude at which the antenna approaches the tower. 
  The tiller also keeps the antenna from rotating sideways. I found this 
was the key ingredient to being able to tram large antennas very easily.

Sounds like the rope method works fine for you on the small antennas, 
but I wouldn't give up on the tramming method for raising that 80M dipole.

73
Randy K0EU

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