I have an 85' free-standing tower that is actually built from construction
elevator mast made by Scando. (more about that another time) It is about two
feet square and built to handle several tons of elevator load, but you can't
reach around it, and can't easily climb the inside. I need to climb it to
disassemble it, move it to a new site, and reassemble it, not to mention
rigging antennas on it.
I am planning to climb this with a mountain climbing seat harness and
climbing rope in a "belayed ascent" with techniques I learned in the army.
For those who aren't familiar with the technique, it works something like
this:
1) The climber clips into one end of a climbing rope, (or preferably the
middle of the rope doubled over if you have enough rope) and then on his way
up the tower, he clips into the tower with caribiners (climbing-grade snap
hooks, not the cheap ones sold at Home Depot)
2) A second person on the ground is "on belay" with the bottom of the rope
through a rapelling friction device, letting rope out as the climber
ascends, but ready to check a fall with the friction in his rapelling
device.
3) If the climber falls he can only fall as far as the last support he
clipped into the tower.
4) Then when he reaches the top and is secured with a second short safety
line, by pulling the rope out of the safety caribiners, and attaching the
middle of the rope to a caribiner at the top of the tower, he can rappel
down in one easy descent.
5) During the rappel down, the assistant on the ground can perform "bottom
belay" by keeping light tension on the rope, which slows the descent, or
stop it altogether with firm tension on the line, which locks the climber's
rappelling friction-device.
For attaching caribiners to the tower, since the tower members are too fat
for the clip opening on a standard caribiner, I am going to use a few links
of heavy grade chain to reach around the member, and then attach the
caribiner to the chain ends. This will also let the caribiner hang cleanly
with no side load (which they aren't well designed for).
This may not meet commercial tower climbing practice, but it sure seems safe
to me, probably safer than the way a lot of towers are climbed. It will be
an easy climb up, and a heck of a lot less work getting down.
That said, I would welcome comments and suggestions.
- Tom Scott
KD7DMH
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