"Jack Erbes" wrote in message
...
Meindert Sprang wrote:

It doesn't even have to get overheated. Solder flows, also in cold
condition. You can test that yourself: tin the end of a stranded wire,
put
it into a screwterminal and tighten it. After a week or so, check if the
screw is still tight: it isn't.

Crimp first. Then apply some solder if you like.


Like I said, some people will argue about it... :)

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.

If the wires are hot enough to melt solder the insulation is also
probably starting to melt away and you have more problems than a simple
loose connection.

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


Also, in a marine environment, a tinned end will
arguably oxidize less and corrode less over time than an untinned end.

I won't argue about that, that is correct. But there is a difference between
tinned stranded wire and stranded wire that is tinned after stripping. The
first doesn't have the wires soldered together and allows the single strands
to set firm in a crimped or screwed terminal. In the last case, you actually
crimp or clamp a 'lump' of solder with some strands in it, without a decent
mechanical cohesion.

And I described crimping a spade lug onto the tinned end and putting
that under the terminal screw, not putting the tinned strands under the
screw.

Same bad procedure.

Some crimpers leave a flattened clamping area that will let untinned
wires shift around in it and then the crimped spade terminal can lose
its grip. I was talking about the average hardware store terminal, put
on with the average hardware store crimping tool, by a non-professional
doing his own work.

These cheap crimpers will do a worse job on tinned ends too. I agree that
untinned strands can shift around, but tinning them first will give you a
solid connection only for the first hours or days. A crimped terminal
applies a constant stress on the copper, which ensures that it holds. If you
tin the ends first, you apply a constant stress on the solder or on strands
clogged together with solder. Eventually the solder flows, trying to release
from the stress and you end up with a connection that is even moore loose
than without tinned ends.

As far as trying to solder on terminal lugs that have already been
crimped on? That sounds nothing short of bizarre to me. To each their
own I guess.

That is a good practise. The stress is on the copper strands only and the
remaining gaps are filled with solder, without stress.

Meindert