One other possibility as the cause of a broken copper wire, now I am talking about a solid wire which is not your case.  A copper wire is strong until there is a nick in it, then it breaks easily at the nick when flexed.  I wonder, if a number of strands of a stranded wire are nicked while one is removing the insulation could eventually result in breaking the wire, eventually.

Rino


----- Original Message ----- From: "Christopher Barber" <CBarber@TexasAttorney.net>
To: "Rotary motors in aircraft" <flyrotary@lancaironline.net>
Sent: Tuesday, August 04, 2009 3:51 PM
Subject: [FlyRotary] Smoking gun, ground wire crimp...

Sorry to side track the T-shirt discussion.  I think we need something more distinctive though to call more attention.  Something "cute" but potent to deliver more of a total message.  Just a thought.

Anyway, Tracy should have my EC2 by now.  Hopefully he is not overwhelmed with work and I will be back with a running engine soon.

Concerned with my broken ground wire, I examined where the wire broke, right at the connection.  I crimped some test wire with the same wire, terminators and crimps and what I have determined is that I MUST have crimped the 16 gage wire with the wrong size crimp (20gage crimp) and the smaller size crimp cut the the thicker wire to a point of failure.  The test crimps I did with the smaller crimps on the larger wire produced the same visual result as what failed.  I have done so many crimps of 20 gage wire, I am guessen' that my motor memory just went to the red crimp. <embarrassed sigh>.

Just a small data point.

All the best,

Chris
Houston

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