Palindr?me wrote:
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 -----------------------------


As another poster has suggested, the heat of a soldering tip may do the
job - indeed some fine wire enamels are designed to convert to a
soldering flux on the application of a hot iron. Dipping the end of the
wire in a solder pot for a few seconds should od the job too.

If you cannot apply heat, then nail varnish remover can work very well.
It may wick up the strands though. Applying a drop of candle wax first
and stripping and trimming back to the wax should work.

If you don't have nail varnish remover, then I guess paint stripper may
do the job..but nail varnish comes with a handy applicator brush.

Another thing that can work is a gas blowtorch with a catalytic
converter nozzle that turns it into a tiny hot air gun. Loads enough
temperature to remove insulation (or heat-shrink tiny sleeves or in a
confined space).

Hi...

Another idea that's worked for me is to simply 'worry' the
ends gently with a pair of long-nose.

The idea is to slightly crush (over and over the strands,
so that the enamel cracks and falls off, leaving the
more flexible copper intact.

Good luck and take care.

Ken