> Are you saying that you can put 500 pounds at the top (while laying
> on the ground) and tilt it up? If it can do that, it should be
> self supporting and not even need guys at all. Also, 500 pounds is
> over 50,000 foot pounds. If the tower is 3 feet wide at the bottom,
> that is 17,000 pounds for your pickup winch. I would venture to
> say a winch
> big would move your pickup instead of the tower. I'd really like
> to believe in this tower but physics keeps getting in the way.
I wasn't able to look at the instructions on the isotruss web site
due to computer problems, which I just spent 2 hours fixing.
I now see on the web site that they are using a 20 foot
ginpole to do the tilting. That's sound physics, but many towers
that don't even claim to be tilt up can in fact be
erected that way. For example, I recently put up an aluminum
tower with a ginpole using that techique. So it still isn't entirely
clear that the reduced weight vs aluminum is that big of an
advantage. Also, the ginpole, to be supplied by the customer,
needs to be stiff enough not to buckle under the load. The
instructions don't say anything about this; they only give the
length. My experience has been that ginpole buckling is the
most unpredictable aspect of this kind of tilt up procedure.
Fortunately, you can lift the tower up a few feet and see
immediately if the ginpole is going to buckle.
See: http://www.mscomputer.com for "Self Supporting Towers", "Wireless Weather
Stations", and lot's more. Call Toll Free, 1-800-333-9041 with any questions
and ask for Sherman, W2FLA.
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