Sooo..... What DID you use as a sealant, now that you've submitted your
credentials, and convinced us all that you know what you're talking about?


"Rick" wrote in message
link.net...
Greg wrote:

As a guess, you have no direct experience using it? If so, tell about
what
you actually did?

Guessed wrong. 8-)

Worked with building, maintaining, and operating manned deep
submersibles to 2000 meters, plus ROV operations and surface marine
industry for over 30 years with a break to go airline flying for a few
years between seagoing endeavors. Am still sailing in the merchant
marine and teach propulsion and sometimes electrical classes at a
maritime academy.

We made up many of our own cables for submersible work and repaired
those that we had commercially built. When I spliced a DC power cable
that supplied my life-support system a mile underwater I did not even
consider using a silicone sealant anywhere on the splice.

The only place we would use those sealants was to seal rubber gaskets in
on devices that were not subject to more than minor pressure
differentials.


The RTV you are referring to may be the 2-part compound that is not
readily available to or commonly used by the DIY'er.

Common references to RTV are to the single component acetic acid and
moisture cured material found in home stores and recreational boat
shops. It will not bond to the wiring jacket and water will wick into
the splice. It will corrode the conductors. It may take a year or so
depending on how severe the exposure and how well the rest of the splice
was made but it will wick and the joint will corrode and fail.

Rick

Rick,
Impressive. Glad you are speaking from personal experience. I respect that
and what you say, but do not agree with you about this.

I shrink mine from the middle out to squeeze out excess RTV. I have not
made connectors like this for deep sea operations. The requested
application was for up on a mast for lighting. The RTV will work fine and
outlast the light fixtures. Acetic acid corrosion has not been an issue on
any of the ones I have made up and/or repaired. Wicking can happen if under
pressure, but I usually only need NEMA4 type connections. I have more
problems from oil or chemical contaminates. Most of my connections are made
up by crimping, soldering and heat shrinking. The RTV was used (and will be
again) for added insurance. I am speaking of the silicon 1 part type that
can be purchased by DIYs. Normally I use the Dow Corning red...cannot
remember the number right now, but I buy by the 12 pack for use on gaskets
for test fixtures. I currently design and build test fixtures for
Whirlpool's product development labs, and am a Controls Engineer by
profession. For years I designed and built control systems for automated
production, assembly, or testing for the US Navy, Chrysler, Ford, Bosch,
etc. and am semi-retired now.

Incidentally, your work experience sounds like fun to me. How do you still
sail in the Merchant Marine and also find time to teach?

Greg Luckett


"Rick" wrote in message
link.net...
Greg wrote:

As a guess, you have no direct experience using it? If so, tell about
what
you actually did?

Guessed wrong. 8-)

Worked with building, maintaining, and operating manned deep
submersibles to 2000 meters, plus ROV operations and surface marine
industry for over 30 years with a break to go airline flying for a few
years between seagoing endeavors. Am still sailing in the merchant
marine and teach propulsion and sometimes electrical classes at a
maritime academy.

We made up many of our own cables for submersible work and repaired
those that we had commercially built. When I spliced a DC power cable
that supplied my life-support system a mile underwater I did not even
consider using a silicone sealant anywhere on the splice.

The only place we would use those sealants was to seal rubber gaskets in
on devices that were not subject to more than minor pressure
differentials.


The RTV you are referring to may be the 2-part compound that is not
readily available to or commonly used by the DIY'er.

Common references to RTV are to the single component acetic acid and
moisture cured material found in home stores and recreational boat
shops. It will not bond to the wiring jacket and water will wick into
the splice. It will corrode the conductors. It may take a year or so
depending on how severe the exposure and how well the rest of the splice
was made but it will wick and the joint will corrode and fail.

Rick






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Rick,
Impressive. Glad you are speaking from personal experience. I respect that
and what you say, but do not agree with you about this.

I shrink mine from the middle out to squeeze out excess RTV. I have not
made connectors like this for deep sea operations. The requested
application was for up on a mast for lighting. The RTV will work fine and
outlast the light fixtures. Acetic acid corrosion has not been an issue on
any of the ones I have made up and/or repaired. Wicking can happen if under
pressure, but I usually only need NEMA4 type connections. I have more
problems from oil or chemical contaminates. Most of my connections are made
up by crimping, soldering and heat shrinking. The RTV was used (and will be
again) for added insurance. I am speaking of the silicon 1 part type that
can be purchased by DIYs. Normally I use the Dow Corning red...cannot
remember the number right now, but I buy by the 12 pack for use on gaskets
for test fixtures. I currently design and build test fixtures for
Whirlpool's product development labs, and am a Controls Engineer by
profession. For years I designed and built control systems for automated
production, assembly, or testing for the US Navy, Chrysler, Ford, Bosch,
etc. and am semi-retired now.

Incidentally, your work experience sounds like fun to me. How do you still
sail in the Merchant Marine and also find time to teach?

Greg Luckett


"Rick" wrote in message
link.net...
Greg wrote:

As a guess, you have no direct experience using it? If so, tell about
what
you actually did?

Guessed wrong. 8-)

Worked with building, maintaining, and operating manned deep
submersibles to 2000 meters, plus ROV operations and surface marine
industry for over 30 years with a break to go airline flying for a few
years between seagoing endeavors. Am still sailing in the merchant
marine and teach propulsion and sometimes electrical classes at a
maritime academy.

We made up many of our own cables for submersible work and repaired
those that we had commercially built. When I spliced a DC power cable
that supplied my life-support system a mile underwater I did not even
consider using a silicone sealant anywhere on the splice.

The only place we would use those sealants was to seal rubber gaskets in
on devices that were not subject to more than minor pressure
differentials.


The RTV you are referring to may be the 2-part compound that is not
readily available to or commonly used by the DIY'er.

Common references to RTV are to the single component acetic acid and
moisture cured material found in home stores and recreational boat
shops. It will not bond to the wiring jacket and water will wick into
the splice. It will corrode the conductors. It may take a year or so
depending on how severe the exposure and how well the rest of the splice
was made but it will wick and the joint will corrode and fail.

Rick






-----= Posted via Newsfeeds.Com, Uncensored Usenet News =-----
http://www.newsfeeds.com - The #1 Newsgroup Service in the World!
-----== Over 100,000 Newsgroups - 19 Different Servers! =-----

"Greg" wrote in message
...
Acetic acid corrosion has not been an issue on
any of the ones I have made up and/or repaired.


I have experienced Acetic acid corrosion in the past (didn't know what to
call it). I used liberal amount silicone on a VHF connector at the mast
head. 3 years later, when I pulled the mast, peeled off the silicone, the
metal connector were almost completely consumed by corrosion.

I suspect that the application was so heavy that the silicone compound
didn't have an opportuntiy to fully cure and the acid in contact with the
metal had a reaction with the metals of the connector..

It's been a few years but I seem to remember a strong acidic smell and the
surface of the remaining metal/mush was damp with this acid.

I stopped using silicone anywhere I would need a heavy buildup that might
trap or hold in the acid.

For electrical connection I stand by my earlier recommendations to purchase
the connectors that have a heavy adhesive shrink sleeving.. They are
expensive but for mast wiring the OP is only going to need a half dozen.

Steve
s/v Good Intentions

"Greg" wrote in message
...
Acetic acid corrosion has not been an issue on
any of the ones I have made up and/or repaired.


I have experienced Acetic acid corrosion in the past (didn't know what to
call it). I used liberal amount silicone on a VHF connector at the mast
head. 3 years later, when I pulled the mast, peeled off the silicone, the
metal connector were almost completely consumed by corrosion.

I suspect that the application was so heavy that the silicone compound
didn't have an opportuntiy to fully cure and the acid in contact with the
metal had a reaction with the metals of the connector..

It's been a few years but I seem to remember a strong acidic smell and the
surface of the remaining metal/mush was damp with this acid.

I stopped using silicone anywhere I would need a heavy buildup that might
trap or hold in the acid.

For electrical connection I stand by my earlier recommendations to purchase
the connectors that have a heavy adhesive shrink sleeving.. They are
expensive but for mast wiring the OP is only going to need a half dozen.

Steve
s/v Good Intentions

Electrical grade RTV Silicone uses a different catalyst than the stuff
that smells like acid. Some of the chalking silicones do too and they
don't smell like acid either. I started working with RTV's 35 years ago
in the lab at GE. I don't recall any of the electrical grade stuff ever
smelling of acid. I first noticed this years later when the chalking
products hit the market. I suspect it is a cheaper product, good enough
to chalk your house but not to be used on electrical stuff. Unless, of
coarse you use acid core solder.

Ron

Electrical grade RTV Silicone uses a different catalyst than the stuff
that smells like acid. Some of the chalking silicones do too and they
don't smell like acid either. I started working with RTV's 35 years ago
in the lab at GE. I don't recall any of the electrical grade stuff ever
smelling of acid. I first noticed this years later when the chalking
products hit the market. I suspect it is a cheaper product, good enough
to chalk your house but not to be used on electrical stuff. Unless, of
coarse you use acid core solder.

Ron

For electrical connection I stand by my earlier recommendations
to purchase
the connectors that have a heavy adhesive shrink sleeving..
They are
expensive but for mast wiring the OP is only going to need a
half dozen.

Has anyone tried Liquid Tape? We have used it in Sat TV work and
it has
worked well in painting the connections and connectors.

Leanne

For electrical connection I stand by my earlier recommendations
to purchase
the connectors that have a heavy adhesive shrink sleeving..
They are
expensive but for mast wiring the OP is only going to need a
half dozen.

Has anyone tried Liquid Tape? We have used it in Sat TV work and
it has
worked well in painting the connections and connectors.

Leanne

Greg wrote:

Incidentally, your work experience sounds like fun to me. How do you still
sail in the Merchant Marine and also find time to teach?

It has been a lot of fun. I now sail for just 4 to 6 months of the year
and only teach the winter quarter.

Rick