Waterblocked cable is constructed to
eliminate this problem. Check out www.falmat.com
. If a non-waterblocked cable is terminated properly to a truly waterproof
connector, there is not much chance of water migration, assuming that the cable
was designed for underwater use and considering the intended depth of use by
typical p-sub. See www.subconn.com for
examples of waterproof connectors.
Karl S.
Luttrell
Science
Diving &Environmental Co.
-----Original Message-----
From:
owner-personal_submersibles@psubs.org
[mailto:owner-personal_submersibles@psubs.org] On Behalf Of Dan H.
Sent: Monday, January 31, 2005
8:06 AM
To: personal_submersibles@psubs.org
Subject: Re: [PSUBS-MAILIST] For
Pierre. Where to buy waterproof connectors
It probably won't matter a lot for a
sub that is only in the water for a short period of time but, after doing some
experimenting, I have found that under pressure, water migrates along a
cable through the strands of wire. To be more exact, in between the
strands of stranded wire. It only takes a few pounds of pressure to move
it along.
That's why when I made my through
hulls for Persistence, I made them with a cavity where
the insulation is stripped off each conductor for a half
inch, then each conductor is tinned with solder and then the
cavity was filled with epoxy. The solder created a road block in the
stranded wire and the epoxy seals the road block and whole cable into the
thruhull. My arrangement also has some mechanical clamping on the cable
jacket.
----- Original Message -----
Sent: Saturday,
January 29, 2005 10:17 PM
Subject: Re:
[PSUBS-MAILIST] For Pierre. Where to buy waterproof connectors
McMaster-Carr (which is the
manufacturer for the cord grips in question) says that its nickel plated brass
liquid tight cord grips are usable in up to 300 ft of water. More than
enough for the scuba depths that you
and I will go to in our wetsubs Pierre. So I believe they would work for our
applications. However, before I buy any of their fittings I have a
few questions about their thru the
hull fittings that I would like answered.
Like for instance....on their
stainless steel fittings description they say.... "Made
of Type 303 stainless steel to provide strain relief for cables outdoors and in
other corrosive environments. Fittings also provide a seal against dirt,
moisture, coolant, and corrosive fumes. All include a zinc-plated steel washer,
neoprene bushing, Viton O-ring, and zinc-plated steel locknut (stainless steel
locknuts are sold separately). Temperature range is -40° to
+250° F. UL listed and CSA certified."
Now these fittings are listed as, and susposed to be
stainless steel. So why is it then that the steel washer has to be zinc plated?
And the steel locknut zinc plated as well but you can purchase a stainless
steel locknut for more money????
It would seem to me that if the fittings are listed as
stainless steel, then they should be ALL stainless. So how come the zinc
plating? You don't need zinc plating on stainless unless those parts are NOT
stainless. In which case only part of the
thru the hull fitting would be stainless and the
washer and locknut would be regular steel with a zinc plating. At least that
appears to be what it is saying, especially since they tell you they offer a
stainless steel locknut seperately (for more money of course).
So if you wanted all stainless I would e mail the
company and clairify if the fitting is ALL stainless steel and if not why then
why do they list it as stainless?
Also the only depth ratings they gave their fittings
were for the nickel plated brass ones up to 300 feet. They do not say what
their depth rating is for the nylon ones or any of the others. It would be
worth it to drop them an e mail to find out some answers
before purchasing, that is what I am going to do
before I buy mine.
So on the one hand it would appear
they are just what we need, but a few questions need to be answered first.
Here is the link to their homepage.
Click on the link at the top that says "e mail" and it will open a
page where you can type a message to them and give your e mail so they can
answer. They do not have their e mail address listed directly, and
----- Original Message -----
Sent: Sunday,
January 30, 2005 7:05 PM
Subject: Re:
[PSUBS-MAILIST] For Pierre. Where to buy waterproof connectors
Can those liquid-thigth cord grips
be used as ambient throuth-hole? They look like so to me...
----- Original Message -----
Sent: Saturday,
January 29, 2005 11:35 AM
Subject: Re:
[PSUBS-MAILIST] For Pierre. Where to buy waterproof connectors
Below are several links where you
can purchase waterproof connectors.
----- Original Message -----
Sent: Thursday,
January 27, 2005 9:31 PM
Subject:
[PSUBS-MAILIST] waterproof connector
Also, where do you buy your
waterproof connectors?
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