I always try to achieve a good soldered joint between conductors in addition
to a rigid mechanical coupling. The soldered joint is not expected to give
the slightest mechanical support, and, by the same token, I never count on
the mechanical support to provide the slightest degree of satisfactory
electrical connection. Each has its separate job, and only that, to do.
I have found that over time solder which contains lead turns dull and tends
to crumble. For outdoor applications, I only use solder which is 96 percent
tin and 4 percent silver. I get this from Radio Shack, fully realizing that
there must be more economical sources of supply, but I haven't taken the time
to learn them. I have not tried the lead-free solders which use antimony. A
100-Watt American Beauty iron (still running perfectly with its original
element after 59 years of steady use) does the heat trick in all situations.
When soldering ground connections to 1-inch copper pipe, I pre-heat with a
blow torch and then do the actual soldering with the iron. (The blow torch's
very high heat "blows" the solder away if the flame even gets close to the
solder).
Done this way, soldered joints stay strong and shiny indefinitely.
Asphalt-based tree wound paint is an effective coating, but it is ruinous
when it gets on clothing. Also, no tape will stick to it .
If you prefer to use tape, my experience has been that no vinyl or
fabric-based (e.g., duct tape) has ever lasted more than a few months here.
Interestingly, a high quality masking tape, such as 3-M brand and the blue
masking tape used by painting contractors, seizes up very nicely around
whatever it is wrapped. The only problem is that its non-sticky surface gets
brittle over time. I use this masking tape over the wire joint or coax
fitting, and then use a self-fusing silicone or rubber tape on top of that.
The next time you see the telephone or TV cable truck doing line work in your
neighborhood, chat up the lineman, and you might even get some of the
self-fusing tape he uses. I do recommend using the masking tape underneath,
for it keeps the joint or fitting from getting gunked up from the self-fusing
tape, and this makes for a happier situation if you ever decide to open up
the joint or fitting at some future time.
73,
Charles, W2SH
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