On Sat, 14 May 2005 13:38:12 +0100, Will wrote:

I have some Sony in-ear headphones. The lead to one earpiece has
been cut through completely and I want to rejoin the two wires
(which I will call 'conductors' to avoid confusion).

The two 'conductors' inside the lead are rather thin. And what is
more, each of the two 'conductors' is made up of something like a
dozen smaller copper wires which are woven around some very fine
threads (perhaps the threads are very fine polyester yarn). The
threads run along the lead as the core of the 'conductor'.

The wires of one of these two 'conductors' looks like bare copper
and is unoxidised so I can probably solder to it. But the OTHER
CONDUCTOR is the PROBLEM because its fine wires are enamelled.

How can I remove this enamel coating in order to be able to solder
to the fine copper wires of the 'conductor'?

Below is what I have tried.

Can you advise?

Will

----------------------------

Maybe my general technique is not delicate enough or maybe I am
being too clumsy but this is what I have tried with no success:

(1) Using fine glasspaper but it seems to tear the fine wires
rather than strip their enamel away. Even if the wires don't
break, there is still a portion of uncleaned enamel of the inner
sides of the fine wires.

(2) Using a match to burn off the enamel but this leaves a black
deposit which I have to scrape away with glasspaper and I am back
to the beginning.

(3) Using a gas flame always seems too fierce as it burns through
the wires.

----------------- END -----------------------------
I've done this several times. The technique used is to put the tip of
the soldering iron under the wire so that it just touches it. Then
apply solder and it will melt on the iron tip and surround the wire.
You will see a little dimple where the wire enters the solder blob.
When the laquer burns away this dimple will disappear and the solder
will flow a little way along the wire. Remember you will be burning
off the laquer and the plastic fibers. After tinning all the wires
then they can be soldered together. BTW, I think Sony uses clear,
green, and red laquer. The wire with the clear laquer will appear to
be bright copper but is actually coated. This wire is the common.
ERS