The Nylock nuts that went bad were a one time use. Some faced up, some
down and some were horizontal to the North so UV shouldn't have been a
problem. I wish I'd kept a few, but my shop needs a good cleaning of
things "I might have a use for someday" I have trouble throwing things
away.
As far as appearance, the nylon appeared to be "eroded" from the top, or
outside. None displayed any sign of deterioration from the bottom where
they had the most protection. I wonder if it could be corona? We do get
a lot of lightening in the area. I have had good luck, "sealing" the
Nylon with liquid electrical tape and epoxy although it's a bit messy
when used "up there".
We are up wind from two large chemical plants to the ESE. The wind is
from that direction roughly 10-12% of the time. From the SW about 30%
and "roughly" evenly divided on all other headings.
When we first lived in town (61-66) pollution could get pretty bad, but
in recent decades, it's probably better than out in the farming country.
Temperature extremes are only about -10F, (-23C) to maybe 150 (65C)
degrees in the bright sun for those on top of antennas
Via the prevailing winds (~30% SW) we are down wind from a large flat
land farming area (15 to about 60 miles), Grand Rapids (85 Mi),
Kalamazoo (115 Mi), and the Chicago, Gary Indiana areas.(205 Mi)
Detroit (120 Mi) and Flint (~60) sre in that ESE to SSE quadrant.
There is a lot of brush / junk timber for many miles in most
directions, The kind of trees that are soft wood, fast growing, die in
a few years and decompose rapidly. Many can be broken up with your bare
hands within 2 years after they die. It comes right up to my yard on
the N and W sides.
That is the environment as near as I can figure. None of the antennas
are close to chimneys or furnace exhausts. So over the past two
decades, I cant think of anything that sets this area apart from
others. So it's likely many lots/batches of nuts were used. In 61, I
flew most of the way to Traverse City following the plume from a
chemical spill. Mostly Chlorine, "I think"
That plume was no more than a bit over 2 mile across after traveling a
good 100 miles. The winds were light and apparently an inversion at a
couple thousand feet.
Those days are long gone. I've lived here since 84, or about 31 years
and have never detected a smell from those plants. The farmers do
inject Ammonia into their corn ground. Likely many thousands of tons
over that downwind area.
Any thoughts as to why I've had such poor luck while others have had
good luck.
73
Roger (K8RI)
On 1/11/2016 Monday 3:15 PM, Patrick Greenlee wrote:
The only problems I have had with Nylocks are:
1. welding too close to them and softening the plastic., and
2. reusing them too many times.
If there had been any UV deterioration problems within my personal
experience I would start painting over the exposed Nylon with a
UV/environment proofing material to ameliorate the effect.
Nylocks are just too nifty and convenient to stop using them because
UV eats them (if it does in any specific circumstances.)
On 1/11/2016 11:22 AM, David Robbins wrote:
two things... I have never had a problem with nylocks used on the m2
antennas and have had some up for quite a few years now.
Roger, I believe you, but you are the only person I know who's had
problems with nylock nuts. I think you got a bad batch.
Chris
KF7P
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