An alternative to sash weights is 3 or 4 inch plastic pipe capped on
both ends filled with gravel or small stone. Small hole at bottom to
drain water, Eyebolt with large washer inside through top cap. Caps
glued with the usual cement that blends the cap with the pipe
material. Can set the weight as needed. I have found I can
camouflage the white pipe very nicely with spray cans of grey, brown
and black. Using black UV resistant sheathed cord, the weights
"disappear" into the woods.
The caps have rounded edges, at least here they do, and the long form
factor will not snag on anything.
Using these and MARINE GRADE ball bearing pulleys, will give you
support that can't be jerked apart with sudden half ton impulses when
the tree is swaying and suddenly hits the end of give in the support
system. This is caused by adding the wind's static pull to the
arresting moment when all the rope is pulled out.
You can also use a pair of pulleys to give the tree a 2:1 advantage
and double the weight. This allows 5 feet of weight movement to
compensate for 10' of tree movement. Other tricks can give the weight
a graduated effect that increases as the tree pulls more rope. This
works by spreading out the increase in arresting force so that the
tree motion times weight does not appear suddenly on the wire, greatly
reducing the peak force.
Without the tension mitigation above, one has simple tree-supported
antenna wire and support strength correctly sized when the components
can be used to lift one end of a car without snapping. Either way
works. The latter will pull branches out of trees in storms.
Note that this doesn't work for typhoons and hurricanes : >)
73, Guy.
On Wed, Mar 17, 2010 at 5:56 AM, Jonathan white
<jonathan.white20@btinternet.com> wrote:
> A big thanks to everyone who posted.
> Firstly the top wire is mechanically failing , I think due to
> wear/abrasion ,also I dont think there is enough movement in the
> elastic cords .
> I use the usual precautions for reliving stress at connection points,
> the thing is there is a solder joint in the flexiweave that has shrink
> wrap applied but that is fine.
> So after reading all the letters its going to be copper weld,remove the
> elastics and go back to using sash weights.
> Someone asked if the vertical was tube,no its h/d 300 ohm feeder joined
> up top/bottom .
> Got myself a decent slingshot/catapult yesterday as I broke the last
> one,ha ha.
> Just a slightly different,antenna my home brew 44` vertical Cebbik
> vertical works a treat one I optimized the feeder length.long live
> open wire feeders ;-)
>
> Thanks again
> Jon G8CCL
> _______________________________________________
> UR RST IS ... ... ..9 QSB QSB - hw? BK
>
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UR RST IS ... ... ..9 QSB QSB - hw? BK
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