Jeff wrote:
> US Tower has been vague on the proper maintenance for
> the MA-Series towers. Does someone on the reflector have
> some information? Do I need to lubricate the cables, etc...?
Hi, I have had an MA-550 up for about 10 years out here.
Had the cable rust through and break about 3 years ago!
Happened for two reasons: (1) I was careless about keeping
some sort of rust prevention spray on the exposed portion
of the cable on the winch; it was a section of the cable
which spent the great majority of the time wrapped on the
winch which is where most of the cable is when the tower
is up. I had lowered the tower for a period of heavy winds,
so most of the cable was off the winch. When I started to
raise the tower again, it got up several feet, but as the
rusty part of the cable began to coil again around the winch--
wham! Cable snapped, down crashed the telescoping sections
which drove the top section right down through the "stop" plate
at the top of the bottom section, and the boom of my Force
12 C4 antenna snapped off at the boom mounting plate!!
So, at least keep an antirust "lubricant" on the cable on the winch!
I am now using a product called "Whitmore's Wire Rope
Lubricant", it comes in a spray-on can. There are others out
there.
Odd, but none of the cable which was "out", that is the run you
can see up the side of the tubular sections was rusted at all;
just the coils on the winch seem to rust over. Suppose the water
tends to stay there, while the sun dries the exposed wire rope
rapidly.
(2) Don't forget to use a grease gun on the bearing on the
rotating base assembly if you are using the MARB base.
(3) Good idea, I think, to put a little "bar and chain" lubricant
on the upper "collar bearing" of the MARB base also. That is
a specially formulated oil for the bar of a chain-saw over which
the chain rides at a pretty high speed. This oil seems to adhere
very well and, to me, seems ideal for that upper collar support
surface.
I expect to get a lot more years from my set up here, as I
now am taking better "care" of same, hi; note I
had to buy a new tubular assembly because of the damage
done when my cable broke!! The local Kauai club has a member
very handy with welding stuff; he was able to rebuild my old
550 to a single telescoping section for use at our Field Day
site. You can see the installation of my new 550 in the old
MARB base as well as the rebuilt 550 at our Field Day site
here on the island at:
http://www.karc.net/Activities/Photokh7m.htm
We spliced the C4 boom back together and it is on the new 550 now.
The two thumbnail photos at the bottom left show the old
re-fabbed tower as set up at Field Day. Russ even put it on
an old boat trailer for easy hauling about the island!
73, Jim KH7M
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