For a period time, in VT, I had a tree service guy who was a ham come
in, and he tied two pulley's in place for me. This was essentially
free, while he was
doing some other tree maintenance work.
Unfortunately, he could only manage about 80', while my bow and arrow
technique got me to treetop height, another 50-60' higher.
n2ea
On Oct 19, 2009, at 11:57 AM, Wes Attaway (N5WA) wrote:
> Here are some further comments re Jim's info regarding possible use of
> pulleys to overcome the effects of sap and tree growth.
>
> 1. Method #1 is to simply haul a pulley with a line through it up
> to the
> correct height. Tie off the line holding the pulley and forget
> about taking
> it down after sap and tree growth consume the rope over the
> branch. This
> method works well for antennas whose ends are supported by trees.
>
> 2. Method #2 is more complicated, but solves a problem that arises
> if you
> need to hold the center of the antenna up midway between two
> trees. I have
> this situation with a Carolina Windom whose center needs to be held
> up by a
> large branch, high up in the air, which was conveniently near where
> the
> center support point was.
>
> After you get your line over the appropriate branch you can then
> carefully
> pull 3 or 4 separate lengths of fishing line over the branch.
> Then, and
> this is the fun part, carefully weave a separate length of 1/16"
> Dacron line
> into a secure knot around the limb. This line will have a pulley
> on it and
> the pulley will have your larger 3/16" Dacron line running through
> it. You
> can do this by using one fishing string at a time to repeatedly
> pull the
> Dacron line around the limb, crossing the lines each time so that
> the Dacron
> line is secure on the limb with the pulley hanging underneath. You
> can yank
> the fishing lines and break them off after the last pass.
>
> At this point you have a pulley at the right spot and your antenna
> haul rope
> through the pulley. There will be no way to get the pulley down
> but that
> doesn't matter, and neither does sap or tree growth. Your pulley
> will be
> secure and there will be no abrasion of the rope that holds the
> pulley, as
> there otherwise would be.
>
> You have to sort of guess at the correct length of the 1/16" line
> so that
> you can get several turns around the limb and still have the pulley
> hanging
> down a few inches below the limb.
>
> You will have to give this some thought to see how it works. I can
> tell you
> that it works well. It is surprisingly easy to do once you get the
> initial
> line over the right spot. You do have to be very systematic. It
> is best if
> you don't try this on a windy day.
>
> I have tall pines and large oaks that wave in the wind. I have
> never had an
> antenna come down using either of these methods.
>
>
> ------------------ Wes Attaway (N5WA) ------------------
> 1138 Waters Edge Circle - Shreveport, LA 71106
> 318-797-4972 (office) - 318-393-3289 (cell)
> Computer Consulting and Forensics
> -------------- EnCase Certified Examiner ---------------
>
>
> -----Original Message-----
> From: towertalk-bounces@contesting.com
> [mailto:towertalk-bounces@contesting.com] On Behalf Of jim Jarvis
> Sent: Monday, October 19, 2009 10:16 AM
> To: Michael Ryan; towertalk@contesting.com
> Subject: Re: [TowerTalk] tree strung dipoles
>
>
> I have 1/8" olive drab dacron line which I favor. For longer term
> installations,
> I also have some 1/4" o.d. dacron. Have used both with a low
> profile carolina windom
> here in NJ.
>
> I bought some 1/8" kevlar line, black, as well, but find that's a bit
> stiff and
> heavier than the dacron. As a result, it's harder to get launched.
>
> My technique is to use a fishing arrow and game-tracker system.
> The game tracker
> string is 15 lb test. Depending on tree height, this may get you a
> direct from
> game tracker to 1/8" dacron transition... for taller trees, you may
> need to use some
> intermediate string... and I bought a reel of mason's string from
> Home Depot for $5 which
> serves that purpose.
>
> Based on experience, I've settled on #12 insulated flexweave wire as
> my standard,
> and have run up to 1.2 kw without end insulators, by simply tying a
> loop in the wire,
> and another in the dacron line.
>
> One caveat: When working with pine trees, the sap will glue the
> rope to the tree,
> resulting in real stress on the antenna. It will be nearly
> impossible to pull the line from
> the tree, if you want to take the antenna down. Thus, in this
> situation, I would favor
> use of pullies.
>
> Up in VT, I had a 160m windom held up by 1/4" o.d. dacron, between
> two 140' pine trees.
> Came time to bring it down for some maintenance. I wound up having
> to tie a turning block
> to a line at the base of the tree, and run a line down to my jeep,
> 100' away. I backed down
> the driveway a reasonable distance, heavily tensioning the line.
> Then, suddenly, it went
> slack.. as a branch came down from on top, 4" in diameter!
> The damned dacron rope
> was embedded in the thing by almost 1/2", and glued fast with sap.
>
> The mass of that branch coming down from 100' would have killed
> anyone under the tree.
> Appropriate caution is advised.
>
> N2EA
>
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