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Old December 28th 03, 08:44 AM
Ian Jackson
 
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In message , Tom writes

"Radioman" wrote in message
...
We used to have some stuff in the Air Force called "F-4 tape" which
worked great for this sort of thing. It's kind of like a putty tape, in
rolls with plastic separating each layer of the tape.


a.k.a. 3M Scotch 70 Silicone Fusible Backshell Tape, apparently.

Sounds like good stuff... sort of the high-tech, stable-silicone big
brother of the less-expensive self-amalgamating rubber electrical
tape. Not cheap, though... list price for a 1" by 30' roll is on the
order of $30 in quantity, over $38 in onesies. Ouch.



I'll just stick to Coax-Seal (tm)
http://www.coaxseal.com/

Same here. I've been using Coax-Seal for years now. I have yet to find
anything better or easier to work with.
When I do have occasion to take the connectors apart the sealant can take
some minutes to remove, but the connections look just as clean as the day I
put them up.
I would suggest one thing. When storing Coax Seal in the shack, especially
after you have opened and used part of it, be sure to store the remainder in
an airtight container of some sort. If you don't, it has a tendency to dry
out and lose it's elasticity. (this takes a couple of years, so don't be
alarmed) I store the unused portion in a simple zip lock sandwhich bag that
I press the air out of before zipping it closed.



Tom,
From the pictures on the website, 'Coax-Seal' looks exactly like
ordinary self-amalgamating tape (as I know it). The cut-away picture
shows that it does not actually bond to the plastic outer of the coax,
which enables you to open up the connection in the future.
However, I would still prefer to give the parts a spray of WD40 before
the connections are made, make the connection, spray again to ensure
that the threads are wetted, wipe off the obvious surplus (but not
trying too hard, so there are still traces left). You then apply the
tape, stretching it somewhat as you go, ensuring that you keep a nice,
even tension. You end up with a tight-fitting, waterproof rubber boot
around the joint, with the WD40 trapped inside to resist any tendency to
corrode.
I think the only argument is whether to use WD40 or not.
Ian.

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