[TowerTalk] Scotchkote and Liquid Tape

[John]

This last Saturday and Sunday, <a href="http://www.gars.org>GARS</a> just put
up a six-meter antenna and replaced the UHF link antenna for the 2-meter
repeater.  We used 3M Cold-Shrink Wrap tubing for the bottom layer, then a
layer of Scotchkote, making sure to overlap onto the cable jacket by at least
1 inch, then a layer of 33+, overlapping by half-width and no
"stretch-until-it-tears."  We feel that this will provide the highest level
of protection on the connections with the easiest removal, if need be.

CoaxSeal, Liquid Electrical Tape and Plasti-Dip will all do a good job
protecting against moisture.  They are, however, very nasty if you ever have
to remove them.  With Kurt's method and ours, all you have to do to remove is
make one quick cut down to the connector/jacket and peel like a banana.  No
goop gets into the connector, gumming up the threads and making it hard to
unscrew or use again.

The Cold-Shrink-Wrap tubing is neat stuff.  It's a rubber-like tube that's
held in tension by stiff spiral plastic inside the tube.  The spiral extends
down through the tube.  In order to activate it, you put it over the joint to
be sealed and pull the plastic past itself out one end.  The other end, not
being held up by the plastic any longer, collapses onto the joint, making a
nice conformal wrap.

--John K.
  KF4MZD

Kurt Andress wrote:

> Hi all connection Goopers!
>
> I agree with K7LXC's comments on the differences between Scotchkote and
> Liquid Tape.
> Specifically, the Scothkote is made for waterproofing completely immersed
> connections, whether they be underwater or underground. Hence, it doesn't
> need UV resistance for its intended use.
> I've seen the UV attack the Scotchkote, but I was taught to use it in a
> manner that significantly reduces the chance for UV degradation to cause
> moisture to leak into the connection.
>
> This is the topic of another post, back in the TT archive.
> Everybody has their favorite method. Here's mine.
>
> For connections that can be sealed with a spiral wrap of electrical tape,
> like two pieces of coax with a barrel connector:
>
> Assemble the connection and apply a light to medium coating of Scothkote.
>
> Allow the coating to dry to a slightly tacky surface. Do not let it
> completely dry to a non-tacky surface. The coating should extend past the
> connection onto the jacket for at least 1".
>
> Wrap your 33+ or 88 over the connection using an overlap that is 1/2 the
> width of the tape. Pull tight when going over the steps in the connection
> to prevent wrinkling.
> Cut the tape with a knife or razor blade, Don't pull it till it breaks.
> Gently lay down the cut end so that it doesn't have a great deal of
> tension.
>
> Coat again with Scotchkote, just for good measure.
>
> I had 4 such connections up for 10 years at my old qth, 8 miles from the
> ocean. I had to cut the tape with a razor blade to get it off, but the
> connecting surfaces were still shiny brite.
>
> --
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>
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