Topband: G10, GPO3 was Re: rohn insulators

[George Dubovsky]

On Fri, Dec 18, 2015 at 8:57 AM, Tim Shoppa <tshoppa at gmail.com> wrote:

> I notice that the G10 insulators I have made (wire insulators, turned or
> cut on my crude home tools... I don't have a tower!) start out "G10 green"
> but then turn brown after a few years in the weather. I suspect this is UV
> although I cannot rule out cut fiber ends absorbing something (moisture?)
> and then turning brown. It seems somewhat worse at the rough cuts I have
> made than on the "shiny from factory" surfaces although both turn brown.
> This browning never happens in indoor G10 applications.
>

​It's UV degradation.​


>
> Is this entirely cosmetic?
>

​It's structural damage. The next step is for the binder to disappear from
the surface, leaving the fiber strands to stand out like a rough pair of
wool socks. A coat of just about any exterior paint will protect the
material. I use Rustoleum and I have some fiberglass insulators in service
for over 10 years with no apparent degradation.

73,

geo - n4ua


> I really like G10 as a material in the workshop because it combines
> toughness with being easy to work (especially the ability to punch holes in
> thin sheets.)
>
> I have also been using the red GPO3 Electrical Fiberglass in indoor HV
> applications, it is a very nice material but wears the heck out of saws or
> drills that are not carbide. I might try some outside.
>
> Tim N3QE
>
> On Fri, Dec 18, 2015 at 5:59 AM, Stan Stockton <wa5rtg at gmail.com> wrote:
>
> > Those look identical to the ones I made for my 8m 4 Square Towers.
> > Use G10, not just any fiberglass.  The G10 rod is more like $20.00 per
> > foot retail, unless you do a little searching.  The one thing I would
> > do differently is add a washer over the machined ends of the
> > fiberglass insulators to put a flat against the unturned portion of
> > the insulator instead of the sharp edges from the ends of the tower
> > legs.  Those sharp edges can splinter the fiberglass.  Also if you
> > span the joint with flat G10 material (maybe 4 inches wide by 18
> > inches long by 3/8 inches thick) it will at least reduce if not
> > eliminate the lateral movement.
> >
> > I have Fiberglas rod guying them now but for many years had four 70
> > foot towers unguyed with this setup at the base.
> >
> > It is interesting that a lot of hams are let's say "thrifty" but when
> > it comes to having something made or making it themselves to save
> > hundreds or even thousands of dollars, many will pay whatever it takes
> > to buy the end product.
> >
> > http://k5go.com/40-meters/
> >
> > 73...Stan, K5GO
> >
> >
> >
> >
> >
> > > On Dec 17, 2015, at 10:43 PM, Merv Schweigert <k9fd at flex.com> wrote:
> > >
> > > 20 mins work with a 5.00 fibre glass rod spun in a lathe,
> > > sort of grossly overpriced exaggeration of a Rohn insulator.
> > >
> > >> I believe there is a slight misrepresentation here. I've never seen
> > these in any Rohn catalog. Rather than
> > >> calling them Rohn 25 tower insulators, I think they are better
> > described as insulators for Rohn 25 tower.
> > >>
> > >> 73, Roger
> > >>
> > >>
> > >>> On 12/17/2015 7:49 PM, w5jmw at towerfarm.net wrote:
> > >>> ok,the station wanting the insulators for a rohn 25.there is a set
> > available from ab5k.he is listing them on e-bay set of 3.look for dxer49
> on
> > e-bay.I believe they are new..73 john
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