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Jack Erbes
 
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Meindert Sprang wrote:

This is not a myth or a point of argument. It is the truth. I learnt it at
school that solder 'flows' when stressed in cold condition. And my personal
experience proves me right too.


Almost everything "flows" under pressure. I like to think of the
process as the material being swaged or formed.

Doesn't the flow stop at some point in the process as the pressure
relaxes? After the crimp is made, a pressure equilibrium should develop
that is the point where the two pressures (the clamping force from the
terminal and the "flow" in the solder) stabilize.

At that point there is a fairly constant and stable mechanical
connection between the two, electricity can flow across it, and it takes
some pretty sophisticated equipment to measure the resistance in the
connection. Simply stated, for the conditions it is good enough for the
job and it works.

Other factors (unsupported weight, vibration, etc.) enter into the
equation as far as the danger of "flow" contributing to conductors being
pulled away from a terminal. If you start shaking the wire, pulling on
it, or applying external heat, things can or will change.

Did you read what I wrote: the wires DO NOT HAVE TO BECOME HOT. SOLDER FLOWS
AT ROOM TEMPERATURE WHEN UNDER MECHANICAL STRESS!


Yes, I did read it, you don't have to yell. My comment about
overheating was in response to your comment:

That's not a smart thing to do. If the connection ever overheats for
some reason...


Anyway, I generally always tin stranded copper wire before I crimp a
terminal on. Have been doing it for years, and have not had any
systematic or recurring problems because of it.

If you can give me a reference that states that tinning stranded bare
copper wires before crimping a terminal on is a bad thing to do I'll
reconsider my ways. Otherwise we are entitled to have differing opinions.

And I pay attention to a number of other things too. Like the length of
the stripped and tinned wire, the type of crimper I am using, exactly
where on the length of the crimping area on terminal the crimp is made,
and the orientation of the seam in the terminal as I crimp it on.

And I give every terminal a good hard pull test after the crimp is made.

Maybe me ought to move on to a less controversial topic, like Talmudic
Law, or Which Religion is Best...

Cheers,

Jack

--
Jack Erbes in Ellsworth, Maine, USA - jacker at midmaine dot com