The message
from "Andrew Mawson" contains
these words:


"Ed Sirett" wrote in message
...
On Wed, 20 Aug 2008 23:40:35 +0100, me9 wrote:

On 20 Aug,
Ed Sirett wrote:

A /proper/ crimper is the best way to join wires.

And a proper crimp for the job. We had a problem on largeish (IIRC
aluminium) cables where the crimp was slightly oversize. Crimping
stretched the cable leading to early failure.

Crimping Ally is way beyond my expertise except. I would treat ally
conductors with great respect.


--
Ed Sirett - Property maintainer and registered gas fitter.
The FAQ for uk.diy is at http://www.diyfaq.org.uk
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Horrid fatigue / work hardening issues with aluminium - lots of
expertise in the US as loads of aluminium wire used during the
Rhodesian coppper crissis.

AWEM

The problems were not only with work hardening but with terminations
into fitttings designed for use with copper wire.

To anyone who's not used to the NEMA 5-15 receptacles commonly used in
the US, these may come as a bit of a shock (!) anyway. Models of
excellent quality do exist, but they aren't what's generally used. And
they tend to run VERY hot, because the plug blades carrying a full 15
amps are usually just a flimsy piece of bent brass strip and the socket
innards are usually no better.

Because alumin(i)um is very ductile, the combination of poor clamping
arrangements for the individual conductors within the receptacle and the
consequent restricted contact area led to the metal flowing away from
the contact point and the heating becoming even more severe as the
contact area lessened and the joint became higher resistance. Quite a
number of major fires resulted and receptacles had to be redesigned if
they were to be rated for use with alumin(i)um conductors.

Alumin(i)um is now restricted, in the main, to uses where the
termination can be very strictly controlled.