On Mon, 29 Jun 2009 14:50:26 -0500, bud--
wrote:

wrote:
On Sun, 28 Jun 2009 00:51:57 GMT, (Doug Miller)

Cite, please.

In aircraft use soldered connections are verbotten because solder
wicks back the cable and the cable becomes brittle - causing vibration
to break the wire. Same in industrial control panels. Not sure of NEC
application in residential wiring - but bad practice, regardless.

Last time I looked at UL508A, which is the UL standard for industrial
control panels, it didn't say anything about solder.

"Wicking" only happens with stranded wires. It is not obvious to me that
a soldered connection is less reliable than a wirenut connection when
exposed to vibration.

The NEC appears to prohibit solder for connecting ground wires in a box
(250.148-E - "solely" is not entirely clear). My recollection is you
can't solder connections for the wire to system grounding electrodes
(GEC). Other than that I am not aware of NEC prohibitions on using solder.

Solder was used into the BX days. The wires were twisted first. I
believe the splice was pointed down and a solder pot was lifted to
immerse the connection. I have seen 2 failures of soldered connections,
one in K&T, the other BX. Both were "cold joints" - the wire did not
bond to the solder. Soldering, when done by a competent installer, is
probably at least as reliable as wirenuts. It is much less convenient,
not cost-effective, and a major PITA if you have to rework the connection.
I thought the OP mentioned stranded wire - but I could be wrong.

I was responding to soldering STRANDED wire.