On 8/27/2010 8:54 AM, Tim Shoppa wrote:
I've had a really nice 130-foot doublet fed by ladder line hanging
between two trees for the past three years.

It's hung using 3/16" black UV-resistant polyester rope in the trees,
and has a pulley and a 15-pound counterweight (plastic jug of sand)
for tensioning at one end.

. . .

But I went ahead and replaced all the rope anyway. With the tennis
ball cannon I actually got the new rope hung a little bit higher than
the old rope.

. . .

For many years I've used a slingshot to put up antennas on Field Day.
Even after just a day or two, they can sometimes be hard to get down,
the twine having dug its way into the tree and gotten gummed up with
sap. After those experiences, I've never been willing to put an antenna
up permanently or semi-permanently by just getting a rope over a branch
-- I've climbed and put a pulley part way up which I've had to replace
every few years as the tree grows out over it.

Of course, larger diameter rope wouldn't cut into the tree as badly as
the heavy twine I use for FD. But I'm sure it would still cut in and get
stuck after even a fairly short period of chafing under tension, and the
tree would grow over and around the rope before long. The result would
be a rope permanently stuck in the tree.

So I'm curious how this ends up working for you. My trees are nearly all
confers -- Douglas Fir, hemlock, sequoia. Are yours hardwood? Are other
folks able to get away with this?

Roy Lewallen, W7EL

On Aug 30, 12:19*am, Roy Lewallen wrote:
For many years I've used a slingshot to put up antennas on Field Day.
Even after just a day or two, they can sometimes be hard to get down,
the twine having dug its way into the tree and gotten gummed up with
sap. After those experiences, I've never been willing to put an antenna
up permanently or semi-permanently by just getting a rope over a branch
-- I've climbed and put a pulley part way up which I've had to replace
every few years as the tree grows out over it.

Of course, larger diameter rope wouldn't cut into the tree as badly as
the heavy twine I use for FD. But I'm sure it would still cut in and get
stuck after even a fairly short period of chafing under tension, and the
tree would grow over and around the rope before long. The result would
be a rope permanently stuck in the tree.

So I'm curious how this ends up working for you. My trees are nearly all
confers -- Douglas Fir, hemlock, sequoia. Are yours hardwood? Are other
folks able to get away with this?

Roy Lewallen, W7EL

Roy -
Let me tell you, I could never be good enough with a slingshot to
get a line over a 120 foot tree! But the tennis ball cannon has
served quite nicely for sending a line over any tree I could find. We
could probably agree to disagree on this - you're good with the
slingshot, and I'm an ace with the cannon.

I find that even in non-conifer trees that it's likely for a 1/4" or
3/16" rope to get stuck after a year or more. If there's a single
crotch with a tight angle in it (e.g. 90 degrees) as opposed to a
number of turns of smaller angles it seems more likely to get stuck. I
don't see how twine could hold up for nearly that long. My
installations are Dacron/polyester rope with pulleys and a
counterweight; the counterweight is IMHO absolutely essential to
having the antenna survive a thunderstorm.

There are also fast-growing pine trees in my neighborhood but they
are "new" and not the giant old-growth trees. In the February
snowstorms (4 feet of snow! Snowpocalypse!) a *lot* of the medium
height pines came down under the weight of the 4 foot snowfall. Non-
evergreen trees also came down but not nearly at the rate that the
conifers did.

Tim N3QE

On 8/30/2010 7:33 AM, Tim Shoppa wrote:

Roy -
Let me tell you, I could never be good enough with a slingshot to
get a line over a 120 foot tree! But the tennis ball cannon has
served quite nicely for sending a line over any tree I could find. We
could probably agree to disagree on this - you're good with the
slingshot, and I'm an ace with the cannon.

I find that even in non-conifer trees that it's likely for a 1/4" or
3/16" rope to get stuck after a year or more. If there's a single
crotch with a tight angle in it (e.g. 90 degrees) as opposed to a
number of turns of smaller angles it seems more likely to get stuck. I
don't see how twine could hold up for nearly that long. My
installations are Dacron/polyester rope with pulleys and a
counterweight; the counterweight is IMHO absolutely essential to
having the antenna survive a thunderstorm.

There are also fast-growing pine trees in my neighborhood but they
are "new" and not the giant old-growth trees. In the February
snowstorms (4 feet of snow! Snowpocalypse!) a *lot* of the medium
height pines came down under the weight of the 4 foot snowfall. Non-
evergreen trees also came down but not nearly at the rate that the
conifers did.

Tim N3QE

I wasn't intending to argue about the best method to put a line over a
tree -- I backpack my portable station as well as camping equipment on
Field Day, which is why my choice of a slingshot and twine. My best
height with it is about 100 feet, but I usually choose my FD sites for
sloping terrain to the east so I don't need much height. My question is
only about the problem of a line getting stuck after a short while. I've
assumed that conifers are more of a problem because of the sticky pitch
and relatively soft wood. What are the experiences others have had with
moderately sized line?

Roy Lewallen, W7EL

On Aug 30, 4:26*pm, Roy Lewallen wrote:
My question is
only about the problem of a line getting stuck after a short while. I've
assumed that conifers are more of a problem because of the sticky pitch
and relatively soft wood. What are the experiences others have had with
moderately sized line?

I've definitely gotten lines of various sizes stuck in tree crotches
if left unmoved for an extended time.

I have been advised, (but have not take the advice!) that running the
rope through a garden hose, which is sitting in the crotch, is the way
to prevent this from happening.

If I were climbing the tree to get the line up there, that'd be easy
enough to do, but using a cannon to send the line over it's not so
obvious. I'm thinking right now, with my 1/4" rope, that maybe I could
use the rope to pull a hose (not as thick as a garden hose maybe) up
itself.

Tim N3QE

Tim Shoppa wrote:
On Aug 30, 4:26*pm, Roy Lewallen wrote:
My question is
only about the problem of a line getting stuck after a short while. I've
assumed that conifers are more of a problem because of the sticky pitch
and relatively soft wood. What are the experiences others have had with
moderately sized line?

I've definitely gotten lines of various sizes stuck in tree crotches
if left unmoved for an extended time.

I have been advised, (but have not take the advice!) that running the
rope through a garden hose, which is sitting in the crotch, is the way
to prevent this from happening.

If I were climbing the tree to get the line up there, that'd be easy
enough to do, but using a cannon to send the line over it's not so
obvious. I'm thinking right now, with my 1/4" rope, that maybe I could
use the rope to pull a hose (not as thick as a garden hose maybe) up
itself.

Tim N3QE

Apparently, tree climbers use a wide strap called a "cambium saver" to
protect the bark and allow lines to run freely. The following link shows
how it may be positioned in the crotch of a branch, and even retrieved
after use, working only from ground level:

http://www.instructables.com/id/How-...ree-without-cl
imbing-it/


Roy, you may have a chance to try this, sooner than you think!


--

73 from Ian GM3SEK
http://www.ifwtech.co.uk/g3sek