>I'm going to be installing a 20' heavy steel mast in my tower (a Trylon 72'
>self-supporting tower). I will be renting a crane to lift the mast and drop
>it from above. What >kind of rigging do I use on the mast so it can be lifted
>up vertically, without the sling slipping up off the top of the mast?
I have always used a clove hitch with an extra turn (
http://www.realknots.com/knots/hitches.htm#mwvsl ) which I tie just above
center of gravity on the mast to prevent tipping on the way up. Never knew it
was called a rolling or magnus hitch. To ensure that this doesn't slide I
usually put a muffler clamp on the pipe for the knot to pull against. A 22 ft.
mast is just about at the limit of my gin pole so sometimes I tie a tag line
(loop) from the lifting line to the top of the mast in order to prevent
tipping.
Tie it good. If I remember right that mast weighed nearly 200 lbs and was
quite a pull.
Earl
N8SS
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