>> Alternately, use an electric winch with a long cord to the
>> control buttons, so the operator can stand well clear of the
>> work zone.
Another alternative is to contain the cable in heavy wall PVC conduit for 20
to 30 feet prior to the capstan.
Properly used the capstan is a great device. Imporperly, or carelessly used
it likes to eat fingers.
>
> I have an electric capstan winch (the TowerJack model) bolted to the tower
> at the base. The capstan requires the operator to pull the excess rope off
> the drum in pretty much a straight line from the tower -- right under the
> tram. I guess the way around that would be to put a pulley on the tie-off
> post (I planted a 4x4 about 20' from the tower for that), and take the
> rope
> off at 90-degrees to the tram. I'd have to add about 30 feet of wire to
> the
> foot switch -- it only has a 10 foot cord now.
This is where I'd make the change.
As you have mentioned above, I have a pulley anchored to the base of the
tower so any pull will be away from the tower. The pulley swivels so the
angle can change. I'd move the capstan out to the side away from the tram
line so that even if the worst happened the antenna could not get the person
working the capstan. That would allow the capstan operator full, local
control yet keep them pretty much out of harms way. The extra pulleys also
keep the "whip" down should that cable break. Should the tram line break
the results depend on where it breaks, how much tension, and of what it's
made.
Relatively speaking:
The "limper" it is (is there such a word?) the less it will whip. The
lighter it is the less it will whip. The more it stretches (relatively
speaking) the more it will whip. I've seen a log chain so heavy I could
barely carry it bust a 2 X 4 right off when it broke. OTH my wife had a
cousin lose the top half of his head when a chain broke pulling a truck out
of a ditch.
I'd "guess" Phyllistran would "whip" and it has enough mass to be potent,
but I'd think it'd lose speed quickly. I'd certainly hate to get hit by it.
Wire rope can be deadly for a ways, but it loses speed and strength in a
hurry. It's unlikely EHS is going to break, but it can be spectacular if it
does. OTOH anything under 400 to 600 pounds of tension when it breaks will
be spectacular and likely dangerous. <:-))
Roger Halstead (K8RI and ARRL 40 year Life Member)
N833R - World's oldest Debonair CD-2
www.rogerhalstead.com
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