I recently put up a small beam for a friend. I used a 4' long piece of 2"
PVC pipe as a trailing tiller, and had my friend tend a tag line attached
to the free end of the tiller. I drilled a hole through one end and cut a
v-notch across the axis of the pipe on the other end.
On the ground, we passed the free end of the tag line through the hole in
the tiller, then placed the V notch over the beam's boom. We then lashed
the tiller on to the boom with the end of the tag line, in an X pattern,
next to the boom-to-mast plate. This held the tiller on with enough
friction to completely control the yaw of the beam and gently control its
rotation about the boom. We found some slip beneficial to allow me (on the
tower), to orient the beam before removing the tiller. No tools are
required to remove the tiller.
To change element angles, as necessary, during the lift, my friend would
simply move to different locations on the ground and vary his tag line
tension gently.
A variation of this, to achieve more friction and still limit the tools
and loose parts required, would be to cut the V notch into the open end of
the tiller (imagine a shark with its jaws wide). Then, cut 2 slits adjacent
to the 'jaws' such that a worm-drive hose clamp can be passed through the
tiller, and around the boom, so that tightening the clamp pulls the boom
into the mouth. Then, only a screwdriver is necessary, and the clamp is
retained by the slots so that it cannot be dropped. I was planning to build
it this way for the next antenna project.
We use simple nylon line as a tag line. I purchased it from the fishing
section at Wal-Mart. It's about 1/8" diameter, has a breaking strength of
over 400lb, and comes in 300' bobbins. Did I mention that it's also
CHEAP?(!)
I also bought a molded plastic kite-string spool in the toy section that
has long, tapered handles on it. This spool comes with 500' of 15 lb test
Spectra cord on it. I took that off (hey, it would make a good tower
plumb-bob line) and was able to wind on 150' of the nylon stuff. The
tapered spool handles make it very easy to spin and wind or unwind the
line. A handy, reuseable tag line.
Hope this helps someone!
--...MARK_N1LO...--
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