Tod Olson wrote:
>
> <snip>
> >the upper pulley is some distance horiz. from the center line
> >vert. of the mast, then the further the mast gets pulled up, the
> greater
> >the horiz sidewise pressure on it, it seems.
>
> I have installed an eyelet bolt facing downward in the top plate
> of the tower. I replaced one of the thrust bearing bolts with the
> eyelet bolt. This places the connection point for the block about
> 3 inches off the Thrust bearing axis. I use a specially made
> clamp on the bottom of the mast which allows the line to attach
> about 3 inches off the mid-line of the mast. I have not noticed
> the binding problem that K4VUD has noticed.
> Tod, K0TO
The concept is good, but beware of lifting heavy loads on hardware store
eye bolts. It is safer to use welded or forged eyebolts designed for
heavy loads. The actual strength of hardware store bolts can vary from
one piece to the next since they are usually not tested and do not have
to meet any particular standard. I have had them fail on several
occasions and have sworn off both those and muffler clamps for antenna
work 20 years ago.
Dave WA1ZCN
Northmark Communications
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