Hello:

Is it safe to use the typical GE RTV silicones against a Polyethylene (PE)
coax outer jacket ?

I know the RTV's use some type of acid (acetic ?) to cure the stuff, and I
was wondering if
anyone might have any first hand experience if there is any kind of
interaction with a coax outer jacket ?

Thanks,
Bob

Bob,

Go to h

http://www.dowcorning.com/content/et..._aas_1ptov.asp

for just about everything you would ever want to know. We use several
grades of electronics RTVs at work in contact with coaxial cable jackets
and all kinds of components to meet DO-160E vibration requirements for
airplave use. The stuff we use does not have the characteristic acetic
acid smell which I think is actually stearic acid.

73,
Larry, W0QE


Robert11 wrote:
Hello:

Is it safe to use the typical GE RTV silicones against a Polyethylene (PE)
coax outer jacket ?

I know the RTV's use some type of acid (acetic ?) to cure the stuff, and I
was wondering if
anyone might have any first hand experience if there is any kind of
interaction with a coax outer jacket ?

Thanks,
Bob

In article ,
Larry Benko wrote:

Bob,

Go to h

http://www.dowcorning.com/content/et..._aas_1ptov.asp

for just about everything you would ever want to know. We use several
grades of electronics RTVs at work in contact with coaxial cable jackets
and all kinds of components to meet DO-160E vibration requirements for
airplave use. The stuff we use does not have the characteristic acetic
acid smell which I think is actually stearic acid.

According to the labels I've read, much of the consumer-grade RTV does
in fact release acetic acid as it cures. Not good stuff to use around
electronics or other metals.

The noncorrosive, "moisture cure" or "neutral cure" RTVs are a better
choice for use around electronics. The ones marketed as "electronics-
grade" are the surest bet in this regard, and usually need to be
mail-ordered. A possible compromise would be the consumer-grade RTVs
which are specifically advertised as being noncorrosive for use on
metals - the labels on these say that they release methanol and
ammonia during cure.

--
Dave Platt AE6EO
Hosting the Jade Warrior home page: http://www.radagast.org/jade-warrior
I do _not_ wish to receive unsolicited commercial email, and I will
boycott any company which has the gall to send me such ads!

ORIGINAL MESSAGE:

Dave Platt wrote:


The noncorrosive, "moisture cure" or "neutral cure" RTVs are a better
choice for use around electronics. The ones marketed as "electronics-
grade" are the surest bet in this regard, and usually need to be
mail-ordered.



*********** REPLY SEPARATOR ***********

Your local pet shop will have RTV made for sealing glass aquariums
which does not release acetic acid or anything else harmful to fish. If
it won't harm fish, it surely won't harm your hardware.

73, Bill W6WRT

On Mon, 13 Mar 2006 18:59:34 -0500, "Robert11" sent
into the ether:

Hello:

Is it safe to use the typical GE RTV silicones against a Polyethylene (PE)
coax outer jacket ?

I know the RTV's use some type of acid (acetic ?) to cure the stuff, and I
was wondering if
anyone might have any first hand experience if there is any kind of
interaction with a coax outer jacket ?

Thanks,
Bob



Bob,
I have been using GE 1200 on coax and connectors since the early
seventies and have never had a problem with it affecting good silver
plated or cheap connectors or the varying grades of coax I have used.
If you want to be fussy cover the connector with electrical tape and
then cover with silicone. This makes it easier to remove but is not
necessary for protecting the connector or the coax. I would not use
it inside of a radio or other electronic equipment but outside of that
it will not hurt and will keep the connection free of moisture, BTW,
if you do wrap it with tape first be sure to coat the coax past the
tape to ensure a good waterproof seal.

N9JBF



I've learned that I don't suffer from insanity, I enjoy it!

Remove the x for e-mail reply
www.outdoorfrontiers.com
www.SecretWeaponLures.com
A proud charter member of "PETAF", People for Eating Tasty Animals and Fish!!!

The advice to avoid acetic-acid smelling RTV because of corrosion is
passed along from person to person like an urban legend, but like an
urban legend it's just about impossible to find anyone who's actually
seen any corrosion result from its use. (A number of queries I've made
over the years has produced just one, using a very early version of RTV.)

I've used the acetic-acid smelling stuff for decades on a variety of
metals including tinned and untinned wire, aluminum, nickel, and copper
circuit boards, and never seen a hint of corrosion. But formulations
vary widely, and my experience certainly isn't exhaustive. I'm not
entirely convinced, though, that among the many formulations there
aren't others, which don't have that smell, which might be corrosive to
some materials.

People who worry about this should buy an industrial product and stay
with it, since there's a much better chance the formulation won't change
in the future without notice.

Roy Lewallen, W7EL

On Mon, 13 Mar 2006 23:14:29 -0800, Roy Lewallen
wrote:

The advice to avoid acetic-acid smelling RTV because of corrosion is
passed along from person to person like an urban legend, but like an
urban legend it's just about impossible to find anyone who's actually
seen any corrosion result from its use. (A number of queries I've made
over the years has produced just one, using a very early version of RTV.)

[snip]

Roy Lewallen, W7EL

HI Roy,

I have been using a different product for over a decade that works
great - liquid vinyl tape. It does a heck of a job for sealing
water-tight connections and, like RTV, doesn'g get hard and crack.
You can buy it a most hardware stores.

Its easy to use and, like was suggest earlier in this thread, I first
wrap the connection with regular vinyl tape (a single layer) before
appling the liquid compond - its makes for much easier removal when
needed.

73
Danny

I was visiting a local SGC dealer years ago as he was troubleshooting a
brand new antenna tuner that was not working. When he opened the plastic
case, that special RTV acidic smell almost knocked us over and all the
tinned circuit board traces and exposed wiring were corroded and black.
SGC claimed they used the wrong type of RTV on a batch of tuners that
was not for electronics use.
Mike


Roy Lewallen wrote:
The advice to avoid acetic-acid smelling RTV because of corrosion is
passed along from person to person like an urban legend, but like an
urban legend it's just about impossible to find anyone who's actually
seen any corrosion result from its use. (A number of queries I've made
over the years has produced just one, using a very early version of RTV.)

I've used the acetic-acid smelling stuff for decades on a variety of
metals including tinned and untinned wire, aluminum, nickel, and copper
circuit boards, and never seen a hint of corrosion. But formulations
vary widely, and my experience certainly isn't exhaustive. I'm not
entirely convinced, though, that among the many formulations there
aren't others, which don't have that smell, which might be corrosive to
some materials.

People who worry about this should buy an industrial product and stay
with it, since there's a much better chance the formulation won't change
in the future without notice.

Roy Lewallen, W7EL

Mike wrote:
Roy Lewallen wrote:
The advice to avoid acetic-acid smelling RTV because of corrosion is
passed along from person to person like an urban legend, but like an
urban legend it's just about impossible to find anyone who's actually
seen any corrosion result from its use. (A number of queries I've made
over the years has produced just one, using a very early version of RTV.)
I've used the acetic-acid smelling stuff for decades on a variety of
metals including tinned and untinned wire, aluminum, nickel, and
copper circuit boards, and never seen a hint of corrosion. But
formulations vary widely, and my experience certainly isn't
exhaustive. I'm not entirely convinced, though, that among the many
formulations there aren't others, which don't have that smell, which
might be corrosive to some materials.
People who worry about this should buy an industrial product and
stay with it, since there's a much better chance the formulation
won't change in the future without notice.
Roy Lewallen, W7EL

I was visiting a local SGC dealer years ago as he was troubleshooting a
brand new antenna tuner that was not working. When he opened the
plastic case, that special RTV acidic smell almost knocked us over and
all the tinned circuit board traces and exposed wiring were corroded
and black. SGC claimed they used the wrong type of RTV on a batch of
tuners that was not for electronics use.

Most likely because they closed the cases before the silicone had cured,
not realising they were trapping the acetic acid vapour inside. The same
can happen in balun boxes and the like.

It would be interesting to know if there have been *any* cases that
didn't also involve some kind of closed situation, or possibly a layer
that was too thick to let the vapour diffuse out.



--
73 from Ian GM3SEK 'In Practice' columnist for RadCom (RSGB)
http://www.ifwtech.co.uk/g3sek

Dan Richardson k6mheatadelphia wrote:
On Mon, 13 Mar 2006 23:14:29 -0800, Roy Lewallen
wrote:

The advice to avoid acetic-acid smelling RTV because of corrosion is
passed along from person to person like an urban legend, but like an
urban legend it's just about impossible to find anyone who's actually
seen any corrosion result from its use. (A number of queries I've made
over the years has produced just one, using a very early version of RTV.)

[snip]
Roy Lewallen, W7EL

HI Roy,

I have been using a different product for over a decade that works
great - liquid vinyl tape. It does a heck of a job for sealing
water-tight connections and, like RTV, doesn'g get hard and crack.
You can buy it a most hardware stores.

Its easy to use and, like was suggest earlier in this thread, I first
wrap the connection with regular vinyl tape (a single layer) before
appling the liquid compond - its makes for much easier removal when
needed.

I've pretty much switched completely to the Plasti-Dip stuff myself. It
is readily available in at least two colors--red and black--at Lowe's.

I used RTV, both the acetic acid and non-acetic acid varieties through
the years. After a couple of unpleasant corrosion experiences with the
acetic acid type, I began either wrapping connectors with vinyl
electrical tape or spraying with acrylic sealant and then applied the
RTV. Either way works well. I recall seeing cautions that one should
be wary of black RTV in that it could conduct. I don't know whether it
can break down but I've used the clear product.

Dave Heil K8MN