RE: Solder vs. Crimp

["Curry, Rene" <Rene@SINECO.com>]

Steven,
What probably happened to your machine is that the solder built up the
diameter of the wire strands, then she crimped it.  Then due to higher
amperage, heat was induced melting the solder and developed a loose
crimp which further exaggerated the problem.
 
Q-List...Another note to add to a previous post on this subject:
Using a piece of scrap wire & scrap contact, you can qualify the
integrity of your crimper and wire/contact combination by performing a
pull test.  This can be done by tying a piece of scrap wire to the
appropriate weight and very slowly lifting the weight by the contact to
see if it will hold the specified pull test. An old drill chuck works
good to hold the contact. (Here we use an Instron Machine)   If you want
to hold your pull test to the highest standards, below are the military
pull test specifications. (80% of that amount would probably do)
 
WIRE GAUGE    PULL TEST IN US POUNDS
26 AW ------------- 7 LBS
24 AWG -----------10 LBS
22 AWG ------------15 LBS
20 AWG ------------19 LBS
18 AWG ------------38 LBS
16 AWG ------------50 LBS
14 AWG ------------70 LBS
12 AWG ------------110 LBS
10 AWG -------------150 LBS    
 
Rene Curry
Grosse Ile, MI
84 5KST

>-----Original Message-----
>From:	Buchholz, Steven [SMTP:Steven.Buchholz@kla-tencor.com]
>Sent:	Monday, May 10, 1999 2:01 PM
>To:	Audi q-list
>Subject:	RE: Solder vs. Crimp
>
>> On mans opinion, here it goes.  When doing electrical work on boats, a
>> notably hostile environment I always use both.  Crimping the fitting than
>> soldering the crimp and the wire.  Afterwards applying a water proof heat
>> shrink tube.  I have followed the same procedures on my car and have never
>> had problems with joints.
>> 
>... a lot of good info being posted, but since there were a couple posts
>that described crimping & soldering I thought I'd post my usual caveat ...
>
>So far everything I've seen posted on the subject has been correct, but if
>you do want to crimp and solder make sure you do it in that order ...
>putting a crimp over tinned wires is likely to cause a high resistance
>contact which may fail in spectacular fashion.  Years ago one of the
>assembler here at KLA was tinning the stranded wire before installing the
>crimp terminals for the power on/off switches ... we found out about it when
>a machine caught on fire in our lab!  
>
>Steve Buchholz
>San Jose, CA (USA)