Insulator Glazing
 

I need to know if anyone has experience based suggestions on how to seal th
e chips in the glazing of the porcelain insulators that are part of some of
the old antenna and mast kits that I have. It would seem to me that the c
hipped glazing is a way for water to saturate the porcelain and render the
insulator ineffective.

Before someone says just replace them let me tell you that they are part of
swaged; as in crimped with metal bands; guy assemblies so there is nothing
short of building new guy lines that would permit the replacement of the i
nsulators.

If you don't have an answer to the question that I have actually asked just
go on to the next posting. NOTHING TO SEE HERE! MOVE ALONG!

Thanks in advance for any help anyone can offer that will actually solve th
e problem.

--
Tom Horne W3TDH

Insulator Glazing
 

On Tuesday, May 12, 2015 at 7:06:31 PM UTC-4, Jim Higgins wrote:
On Tue, 12 May 2015 14:04:01 EDT, in
, Tom Horne
hornetd - gmail dot com wrote:

I need to know if anyone has experience based suggestions on
how to seal the chips in the glazing of the porcelain insulators
that are part of some of the old antenna and mast kits that I have.
It would seem to me that the chipped glazing is a way for water
to saturate the porcelain and render the insulator ineffective.

Porcelain isn't porous, so your concern about the insulators
absorbing water is misplaced.

Before someone says just replace them let me tell you that they
are part of swaged; as in crimped with metal bands; guy
assemblies so there is nothing short of building new guy lines
that would permit the replacement of the insulators.

If you don't have an answer to the question that I have actually
asked just go on to the next posting. NOTHING TO SEE
HERE! MOVE ALONG!

Thanks in advance for any help anyone can offer that will
actually solve the problem.

The problem you're concerned about doesn't exist. Really.

However, one should ask oneself WHY the insulators are chipped? Have
they in fact fractured under load... or have they somehow just gotten
a few surface dings. The latter wouldn't be a problem; the former
would. And the only cure for the former is replacement.

Jim

If ceramic insulators don't take up water why do the manufacturers bother t
o glaze them?

Since the insulators in question are part of old AB-155 mast kits I have co
ncluded that the chipping is the result of frequent handling during erectio
n and striking of the masts. If I do have to make up new guy assemblies fo
r any of the mast kits I will use plastic insulators in tension rather than
ceramic insulators in compression.

Thanks

--
Tom Horne W3TDH

Insulator Glazing
 

In article ,
Tom Horne wrote:

Since the insulators in question are part of old AB-155 mast kits I have co
ncluded that the chipping is the result of frequent handling during erectio
n and striking of the masts. If I do have to make up new guy assemblies fo
r any of the mast kits I will use plastic insulators in tension rather than
ceramic insulators in compression.

My understanding is that the insulators operate in compression mode
for a good reason - physical safety.

Egg-type insulators actually have the two wire terminations running
through one another (at right angles) separated by the part of the
insulator that's under compression. if the insulator cracks or
shatters or turns to dust, the two interlaced termination loops won't
come apart - you lose the insulation, but the mechanical "locking" of
the two wires together remains. The mast (or whatever you're using)
doesn't lose its guy support.

Insulators "in tension" can snap into two completely separate pieces
(one per wire) and the guy will come un-guyed.

Since guying of an antenna mast can be considered to be a
safety-critical application, it's probably better to continue to use
compression-mode insulators which will "fail physically safe".