Dave Plowman wrote:

In article ,
Arny Krueger wrote:

BTW, a good job of crimping amounts to cold welding with the extra
bonuses of high mechanical strength and inherent disruption of oxide
films or dirt on the connector or the wire. Given my choice, I'd pick a
well-crimped connection over the other two, but I would not worry about
a good job based on the other two methods. Crimping and welding have the
disadvantage of not being as field-repairable as soldering.


The other beauty of crimping is that there is no weakening due to heat
close to the joint - perhaps not that important where the lead is
adequately clamped, though. However, *proper* crimping requires a usually
very expensive special tool, and frequently it is only of use for one
specific connector.


And a lot of elbow grease.

"Dave Plowman" wrote in message
...
In article ,
Arny Krueger wrote:
BTW, a good job of crimping amounts to cold welding with the extra
bonuses of high mechanical strength and inherent disruption of oxide
films or dirt on the connector or the wire. Given my choice, I'd pick a
well-crimped connection over the other two, but I would not worry about
a good job based on the other two methods. Crimping and welding have the
disadvantage of not being as field-repairable as soldering.

The other beauty of crimping is that there is no weakening due to heat
close to the joint - perhaps not that important where the lead is
adequately clamped, though.

I don't understand your reasoning.
Electrical copper is, or should be, in a completely annealed state. Heating
the copper up isn't going to hurt it.

I have found, however, that soldered cable connections frequently break from
strain, even if they are correctly soldered. Connections are frequently
repaired over again, due to inadequate strain relief on the center conductor
that appears in large diameter coaxial cable.

"Robert Morein" wrote in message

"Dave Plowman" wrote in message
...
In article ,
Arny Krueger wrote:
BTW, a good job of crimping amounts to cold welding with the extra
bonuses of high mechanical strength and inherent disruption of oxide
films or dirt on the connector or the wire. Given my choice, I'd
pick a well-crimped connection over the other two, but I would not
worry about a good job based on the other two methods. Crimping and
welding have the disadvantage of not being as field-repairable as
soldering.

The other beauty of crimping is that there is no weakening due to
heat close to the joint - perhaps not that important where the lead
is adequately clamped, though.

I don't understand your reasoning.
Electrical copper is, or should be, in a completely annealed state.
Heating the copper up isn't going to hurt it.

Heating disturbs the wire's plastic insulation, which provides a significant
amount of strength and resistance to sharp bends.

I have found, however, that soldered cable connections frequently
break from strain, even if they are correctly soldered.

A crimped connection typically includes some of the plastic insulation,
which strengthens the connection and helps avoid sharp bending near the
connection.

Connections
are frequently repaired over again, due to inadequate strain relief
on the center conductor that appears in large diameter coaxial cable.

Happens with small coax and non-coaxial cables, as well.

On Thu, 27 Nov 2003 07:01:38 -0500
"Arny Krueger" wrote:


Heating disturbs the wire's plastic insulation, which provides a
significant amount of strength and resistance to sharp bends.

Oh please, the last shred of insulation at the end of the wire provides
near zero additional strength, and besides:

1) The cable itself ought to be clamped before entering the strain
relief.
2) If you're melting the insulation you have either crap wire or no
soldering skill whatsoever.

I have *NEVER EVER* had the actual solder joint or copper wire near it
fail in any of the hundreds of leads I've made over the years. the only
failures I have ever had have been fracturing of the wire *after exiting
the strain relief*, and even then only after a good long service life.
(ok so the occasional one had a dry joint too, no-ones perfect)

--
Spyros lair: http://www.mnementh.co.uk/ |||| Maintainer: arm26 linux

Do not meddle in the affairs of Dragons, for you are tasty and good with
ketchup.

On Thu, 27 Nov 2003 07:01:38 -0500
"Arny Krueger" wrote:


Heating disturbs the wire's plastic insulation, which provides a
significant amount of strength and resistance to sharp bends.

Oh please, the last shred of insulation at the end of the wire provides
near zero additional strength, and besides:

1) The cable itself ought to be clamped before entering the strain
relief.
2) If you're melting the insulation you have either crap wire or no
soldering skill whatsoever.

I have *NEVER EVER* had the actual solder joint or copper wire near it
fail in any of the hundreds of leads I've made over the years. the only
failures I have ever had have been fracturing of the wire *after exiting
the strain relief*, and even then only after a good long service life.
(ok so the occasional one had a dry joint too, no-ones perfect)

--
Spyros lair: http://www.mnementh.co.uk/ |||| Maintainer: arm26 linux

Do not meddle in the affairs of Dragons, for you are tasty and good with
ketchup.

In article ,
Arny Krueger wrote:
Connections are frequently repaired over again, due to inadequate
strain relief on the center conductor that appears in large diameter
coaxial cable.

Happens with small coax and non-coaxial cables, as well.

I repair a lot of audio cables, and perhaps the most common is the thin
wire used for personal mics, which near always 'goes' just above the
connector. Sleeve it and it goes at the top of the sleeving. The cable is
often near impossible to replace completely as the mic is usually sealed,
so in practice it's best not to sleeve the connector cord grip at all, as
this involves shortening the cable more at the next repair.

--
*A cubicle is just a padded cell without a door.

Dave Plowman London SW 12
RIP Acorn

In article ,
Arny Krueger wrote:
Connections are frequently repaired over again, due to inadequate
strain relief on the center conductor that appears in large diameter
coaxial cable.

Happens with small coax and non-coaxial cables, as well.

I repair a lot of audio cables, and perhaps the most common is the thin
wire used for personal mics, which near always 'goes' just above the
connector. Sleeve it and it goes at the top of the sleeving. The cable is
often near impossible to replace completely as the mic is usually sealed,
so in practice it's best not to sleeve the connector cord grip at all, as
this involves shortening the cable more at the next repair.

--
*A cubicle is just a padded cell without a door.

Dave Plowman London SW 12
RIP Acorn

"Robert Morein" wrote in message

"Dave Plowman" wrote in message
...
In article ,
Arny Krueger wrote:
BTW, a good job of crimping amounts to cold welding with the extra
bonuses of high mechanical strength and inherent disruption of oxide
films or dirt on the connector or the wire. Given my choice, I'd
pick a well-crimped connection over the other two, but I would not
worry about a good job based on the other two methods. Crimping and
welding have the disadvantage of not being as field-repairable as
soldering.

The other beauty of crimping is that there is no weakening due to
heat close to the joint - perhaps not that important where the lead
is adequately clamped, though.

I don't understand your reasoning.
Electrical copper is, or should be, in a completely annealed state.
Heating the copper up isn't going to hurt it.

Heating disturbs the wire's plastic insulation, which provides a significant
amount of strength and resistance to sharp bends.

I have found, however, that soldered cable connections frequently
break from strain, even if they are correctly soldered.

A crimped connection typically includes some of the plastic insulation,
which strengthens the connection and helps avoid sharp bending near the
connection.

Connections
are frequently repaired over again, due to inadequate strain relief
on the center conductor that appears in large diameter coaxial cable.

Happens with small coax and non-coaxial cables, as well.

In article ,
Robert Morein wrote:
I don't understand your reasoning. Electrical copper is, or should be,
in a completely annealed state. Heating the copper up isn't going to
hurt it.

Don't know the theory, but if you flex a wire close to a soldered joint it
will always break at the joint. Perhaps it's a chemical reaction?

[Thinks.] But don't you have to quench copper if annealing?

--
*Never slap a man who's chewing tobacco *

Dave Plowman London SW 12
RIP Acorn

"Dave Plowman" wrote in message

In article ,
Robert Morein wrote:
I don't understand your reasoning. Electrical copper is, or should
be, in a completely annealed state. Heating the copper up isn't
going to hurt it.

Don't know the theory, but if you flex a wire close to a soldered
joint it will always break at the joint. Perhaps it's a chemical
reaction?

This happens with stranded wire because the stress tends to concentrate at
the point where the solder flow ends. I've pointed out other issues related
to insulation in another post.

[Thinks.] But don't you have to quench copper if annealing?

I don't think so. The usual rule is to quench to harden, and cool off slowly
to anneal.