Not too long ago, someone made an excellent suggestion about how
to insert or remove a long heavy mast from inside a tower.
With 20 ft of tower standing on a GOOD concrete base, OR a set of
temporary guys, assemble another 30 ft of tower alongside and
secured to the 20 ft of "permanent" tower. (A pair of "come-alongs"
or "power-pulls" can be used to secure the temporary tower to the
permanent tower.)
Attach a gin pole to the temporary tower and raise/lower the long mast
into/out-of the permanent tower. Use a large pulley at the base of the
tower and pull out with at least 3 volunteers or a tractor or vehicle.
An alternative to the winch at the top is to simply use a LARGE
pulley supported by a cross bar. The pulleys used by utility companies
to pull cables on power poles are VERY NICE if you can obtain one.
They have a large hook on top and the wheel rides on ball bearings.
WELL pulleys (remember the old water well?) also work well and are
quite inexpensive. I found a six inch diameter well pulley at a local
hardware store for $15. Be sure to secure it with a clamp or rope
rated at least 4 times the load weight. Place another pulley at the
base of the tower, and use a vechicle, tractor, or a minimum of 3
volunteer pullers. A double clove hitch on the mast will hold it.
(I have NEVER seen a PROPERLY tied clove hitch fail). Another
approach I have heard of is to use heavy cable ties to secure the
rope to the mast. (Be sure to use plenty of them! ...and test in a
secured mode before you let loose from the top of the tower!)
de Tom N4KG
.
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