> > > Our club has an old Wilson MT-61 tubular crank-up tower which
> > > is similar to the U.S. Tower MA-550. My friend is going to buy
> > > it from us and put it up at his new QTH, but he needs to replace
> > > the cable before erecting it. Any recommendations on what kind
> > > of cable I should use and where we can get it (I seem to remember
> > > that U.S. Tower has a reputation for not being helpful in this
> > > regard).
>
> Current crank-ups use 7x19 galvanized wire rope of various sizes but
feel
> free to use stainless steel too.
>
> Cheers,
> Steve K7LXC
> TOWER TECH
> _______________________________________________
Steve et al.
There may be a slight problem with recabling the Mt-61.
I did this a few years ago.
The original cables used by Wilson were a size smaller on each section.
Consequently, my desire to upsize the cables would not work with the
existing sheaves. The existing sheaves were too small to accept a larger
diameter cable.
I also wanted to replace the sheaves with better made bearing/bushing
sheaves.
NOTE: Sheaves should always be examined and replaced when recabling if they
show any wear.
But that required rebuilding the sheave brackets to accommodate the
wider/bigger sheaves.
Fortunately I have a torch and a welder and was able to redesign the sheave
brackets.
One problem to be aware of. Cable does have a certain stretch factor.
The method that the Wilson uses can create a problem if you install cables
without out considering the stretch factor.
When the sections nest against their stops, the cable could loose tension
and come out of the sheave groove and snag.
If you must rebuild the sheave brackets, remember to place a guard over the
bracket to prevent a slack cable from becoming misaligned.
The cable supplier will give you a stretch factor figure for the weight the
cable will be supporting.
I'm not affiliated but have had great success, help, and advice from:
http://versales.com
They will supply cables, thimbles, press fittings, and assemble to your
specs.
_______________________________________________
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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