Thanks, Steve. Good stuff. I'm going to try the tiller method. I think
that'll be a much better way to keep the boom from rotating, and it'll also
keep the boom perpendicular to the tram line.
So far, TT members have sent me two methods. One attaches the tiller
pointing towards the tower, and attaches the pull rope to it. Seems to me
this restricts how close you can get to the tower, but that's not a big deal
in my case. I like it because the tiller is held firmly in position by the
haul rope. I don't see how the antenna could turtle or twist. The other
member attaches the tiller pointing back towards the tram anchor and
connects it to a second pulley that rides the tram line behind the antenna.
Any preference?
I haven't searched the archives on tillers yet. That search engine gives me
a headache. Would that I could Google the archives.
We're using an 1800-lb electric winch mounted at the bottom of the tower.
Haul weight isn't a problem. It's just controlling that beast at the top of
the tower. Lots of inertia.
73, Dick WC1M
From: K7LXC@aol.com [mailto:K7LXC@aol.com]
Sent: Sunday, May 11, 2008 11:31 PM
To: towertalk@contesting.com; wc1m@msn.com
Subject: Re: [TowerTalk] antenna sling for tramming
In a message dated 5/11/2008 6:53:54 P.M. Pacific Daylight Time,
towertalk-request@contesting.com writes:
> My techniques works OK on a relatively light antenna like the 40-2CD,
but I
found the heavier SteppIRs have a tendency to rotate in the straps i.e., the
boom rotates) When that's happened, I've had to secure the straps with hose
clamps, but I think this is a bad idea because hose clamps have sharp edges.
I'd like to find a better way to secure the straps to the boom.
Well, the main problem is that the SteppIRs have the elements above the
boom which makes them top-heavy and want to turtle or pitch-pole upsidedown.
The KLM/M2 has the same problem being top-heavy. Just about all other
antennas have the elements below the boom or thru the boom.
Using hoseclamps is okay. Just check your slings after using them. I
doubt any damage will happen.
The only way to get around this is to use a tiller of some sort. It
attaches to the boom and the other end slides up the tramline. There are
discussions in the archives at www.contesting.com.
> Soon I'll be tramming the heaviest antenna I've attempted: a Cal-AV
2D-40A,
at 17 sq ft wind load and 165 lbs. Needless to say, I'll wait for a calm
day. But with such a large antenna. I want to make sure the sling technique
is as sound as possible.
The weight shouldn't be a big problem. It's the top-heavy thing that
you're fighting. BTW you might want to double-block your haul line for an
antenna this heavy. That'll cut the haul weight in half.
Cheers,
Steve K7LXC
TOWER TECH
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