Sounds great, but my experience has been that with a tiller installed and
attached to the haul rope, as you describe, the antenna can't "turtle" or
roll over, so the brackets connecting the boom and sling wouldn't be needed.
73, Dick WC1M
> -----Original Message-----
> From: Randall K Martin [mailto:rkmassoc@comcast.net]
> Sent: Wednesday, September 09, 2009 4:29 PM
> To: towertalk@contesting.com
> Subject: [TowerTalk] tramming vs. "riding the rope"
>
> 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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