I've been using a Sherrill "BigShot" slingshot for years to install
wire antennas in the tall Fir trees around my place.
It will launch a 3/4-inch metal pipe-elbow over 100-plus feet tall trees
w/o any problem. Make sure you paint the weight a bright color to
make it easier to find. Ten feet of a colored line tied between the weight
and spooled-line also helps with the "finding" part of the task.
I use a big spool (about 5-inch diameter smooth spool-ends) of nylon
thread (formerly used by Boeing to sew upholstery used in their planes)
as the messenger line to pull heavier lines .
My process is:
1 - stab a pipe in the ground elevated/pointed toward
the tree-top to be used
2 - slip the spool of line on to the pipe so the line
strips-off smoothly (axially) when weight is launched
(you DO NOT want to have to deal with line breakage
getting the spool to rotate to strip-off line radially).
Note: position the spool so the support pipe barely
protrudes beyond the end of the spool
3 - tie the line on the spool to the weight
4 - stand slightly forward and to the side of the spool
5 - engage the weight in the slingshot
6 - aim/launch
7 - find the weight on the far-side of the tree
8 - repeat 1--7 as needed
NOTE: If you can not locate a useful spool of messenger line,
wind several hundred feet (or more) of line around a plastic five
gallon pail (Lowes/Home-Depot). Secure the launch-end of the
line that feeds the "weight" with a bit of tape. Position the pail over
the pipe as in step-1 so the line will strip off the pail axially from
the bottom-end of the pail.
I have found launching a few weights (stones) over the
tree of interest helps to get a feel for the launching process.
73 Dick/w7wkr at CN98pi
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