It's nearly impossible as you ask since as the angle to the ground
decreases, it is a full person reach upward with more than the tower
weight as the force needed. It's a lever, so holding at 1/4 the length
from the base and man height (5.4', 45 degree angle) the center of mass
exerts more than the tower weight on the people who are then the pivot
point. At that angle of tilt and support point the force on the tower
pivot bolts is upward. I've seen a tower permanently bent when a well
intentioned helper placed a support too near the pivot of a partially
tilted tower.
Something to consider when a stepladder is used as a temporary support.
It might be instantly temporary or bend the tower or both. Also
remember that rotator, mast, and antennas move the center of mass
upward/outward significantly since they are effectively all concentrated
loads beyond 22'.
A derrick or falling derrick is what you need. A couple of sticks of
Rohn 25 as a fixed derrick next to the pivot, with a strong back guy,
some side guys, and a winch. The guys MUST be low stretch, wire or low
stretch rope, NOT nylon.
Grant KZ1W
On 10/13/2017 16:44 PM, Bob Matthews wrote:
Hello All,
I have a Hygain 52SS crank-up tower on a hinged base. Has anyone on here tried
to walk a tower down this size? It's 22 feet nested. Weighs about 400 lbs I
believe. Wondering how many men it would take to walk it down on it's hinged
base from the vertical to the horizontal position on the ground. I don't
believe there's enough room to get a crane in to do this, so I'm wondering how
many people it would take to walk it down.
Thanks in advance for your input.
Bob KT3RR
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