On Sunday, 27 August 2023 at 17:33:07 UTC+1, Pipl wrote:
> On Wed, 23 Aug 2023 22:15:57 -0000 (UTC), Mark Olson
> <ols...@tiny.invalid> wrote:
>
> >I'm [mis?]remembering that soldered connections on vehicle wiring[1]
> >are discouraged- it tends to concentrate stress, IIRC. Better to use
> >a quality crimp connection covered with glue filled heat shrink.
> It makes sense. And solder under a screw terminal is an absolute
> no-no.

I've done a fair number of solder fixes on bikes and cars over the years
and haven't ever had a problem with them. Most of them were in reaction
to a joint of a broken/joined wire that someone else had done using
whatever method. I do always support the joint with heat shrink though
so I'm not sure how fragile that combination is. If it was in a part of a
loom that flexed I could see a soldered section causing some weakness
at its ends since it wouldn't flex as the other part did.

As for solder under a screw terminal, I don't do that. But I do tend
to use those 'bootlace ferrules' that you crimp on just to keep the wire
tidy and reduce the risk of stray strands going where they shouldn't.

On Sun, 27 Aug 2023 09:40:14 -0700 (PDT), Stephen Packer
<stephen.packer@gmail.com> wrote:

>As for solder under a screw terminal, I don't do that. But I do tend
>to use those 'bootlace ferrules' that you crimp on just to keep the wire
>tidy and reduce the risk of stray strands going where they shouldn't.

Ferrules definitely have their place.

I've been using them at work just last week, but for screw terminals
where the wires are trapped directly under the screw. The turning
action of the screw twists the wires out to the side otherwise,
particularly if the cabls is relatively small.

--

-Pip

On 27/08/2023 17:33, Pipl wrote:
> On Wed, 23 Aug 2023 22:15:57 -0000 (UTC), Mark Olson
> <olsonm@tiny.invalid> wrote:
>
>> I'm [mis?]remembering that soldered connections on vehicle wiring[1]
>> are discouraged- it tends to concentrate stress, IIRC. Better to use
>> a quality crimp connection covered with glue filled heat shrink.
>
> It makes sense. And solder under a screw terminal is an absolute
> no-no.

Not quite sure what you mean:

1) Why?
2) When I'm screwing down on a bunched, braided or twisted wire, (like
in a power socket or bulb-carrier) I usually tin, then run solder into
the end to make a terminal/joint that's not going to shed guillotined,
fatigued or otherwise stray strands getting where they shoutdn't.

--
Rusty Hinge
To err is human. To really foul things up requires a computer and the BOFH.

On Sun, 27 Aug 2023 19:19:16 +0100, RustyHinge
<rusty.hinge@foobar.girolle.co.uk> wrote:

>On 27/08/2023 17:33, Pipl wrote:
>> On Wed, 23 Aug 2023 22:15:57 -0000 (UTC), Mark Olson
>> <olsonm@tiny.invalid> wrote:
>>
>>> I'm [mis?]remembering that soldered connections on vehicle wiring[1]
>>> are discouraged- it tends to concentrate stress, IIRC. Better to use
>>> a quality crimp connection covered with glue filled heat shrink.
>>
>> It makes sense. And solder under a screw terminal is an absolute
>> no-no.
>
>Not quite sure what you mean:
>
>1) Why?
>2) When I'm screwing down on a bunched, braided or twisted wire, (like
>in a power socket or bulb-carrier) I usually tin, then run solder into
>the end to make a terminal/joint that's not going to shed guillotined,
>fatigued or otherwise stray strands getting where they shoutdn't.

The reason I was told was that solder creeps, so the connection
loosens over time. Certainly lead anneals at room temperature. That
said, modern lead-free solder might not suffer the same problem.

--

-Pip

Stephen Packer <stephen.packer@gmail.com> wrote:

> As for solder under a screw terminal, I don't do that. But I do tend
> to use those 'bootlace ferrules' that you crimp on just to keep the wire
> tidy and reduce the risk of stray strands going where they shouldn't.

+1

I just bought a ferrule kit plus a fairly good knockoff of a Knipex
crimper when I installed a generator transfer switch that used all
stranded wiring.

--
FJR1300A, GL1000, KLR650A6F, EX250J9A, DR200SE, Vespa Ciao

On 27/08/2023 19:32, Pipl wrote:
> On Sun, 27 Aug 2023 19:19:16 +0100, RustyHinge
> <rusty.hinge@foobar.girolle.co.uk> wrote:
>
>> On 27/08/2023 17:33, Pipl wrote:
>>> On Wed, 23 Aug 2023 22:15:57 -0000 (UTC), Mark Olson
>>> <olsonm@tiny.invalid> wrote:
>>>
>>>> I'm [mis?]remembering that soldered connections on vehicle wiring[1]
>>>> are discouraged- it tends to concentrate stress, IIRC. Better to use
>>>> a quality crimp connection covered with glue filled heat shrink.
>>>
>>> It makes sense. And solder under a screw terminal is an absolute
>>> no-no.
>>
>> Not quite sure what you mean:
>>
>> 1) Why?
>> 2) When I'm screwing down on a bunched, braided or twisted wire, (like
>> in a power socket or bulb-carrier) I usually tin, then run solder into
>> the end to make a terminal/joint that's not going to shed guillotined,
>> fatigued or otherwise stray strands getting where they shoutdn't.
>
> The reason I was told was that solder creeps, so the connection
> loosens over time. Certainly lead anneals at room temperature. That
> said, modern lead-free solder might not suffer the same problem.
>
Hmmm. I don't think that follows:
1) the properties of alloys often bear no resemblance to those of their
constituents - take silver, a soft malleable metal, and mercury, even
softer and don't try to see if it's malleable... The amalgam is neither
soft nor malleable.

2) Take a block of carbon and melt a little silver in a pit in it. Add a
little solder, then let the alloy cool. Solder is ductile and malleable,
likewise silver. The alloy of solder and silver, which I wanted to use
as an inlay into blued steel, proved so hard that files skated on its
surface.

3) Anyway, the simple solder-filled interstices aren't likely to squish
much, if at all. The solder acts as a filler of airspaces rather than
making an homogeneous component.

But I used to use crimped terminals sometimes - I've got nothing against
them, just seldom had them to hand.

--
Rusty Hinge
To err is human. To really foul things up requires a computer and the BOFH.

On Sun, 27 Aug 2023 20:53:12 +0100, RustyHinge
<rusty.hinge@foobar.girolle.co.uk> wrote:

>On 27/08/2023 19:32, Pipl wrote:
>> The reason I was told was that solder creeps, so the connection
>> loosens over time. Certainly lead anneals at room temperature. That
>> said, modern lead-free solder might not suffer the same problem.
>>
>Hmmm. I don't think that follows:
>1) the properties of alloys often bear no resemblance to those of their
>constituents - take silver, a soft malleable metal, and mercury, even
>softer and don't try to see if it's malleable... The amalgam is neither
>soft nor malleable.
>
>2) Take a block of carbon and melt a little silver in a pit in it. Add a
>little solder, then let the alloy cool. Solder is ductile and malleable,
>likewise silver. The alloy of solder and silver, which I wanted to use
>as an inlay into blued steel, proved so hard that files skated on its
>surface.
>
>3) Anyway, the simple solder-filled interstices aren't likely to squish
>much, if at all. The solder acts as a filler of airspaces rather than
>making an homogeneous component.

Fair points, and industry is full of old wives' tales, but I'll play
safe for now at least. A swift Google suggest it's more to do with
cold welds, or rather, the lack of them with solder, plus solder
wicking up the wire causing a stress-raiser, but I have no real
experience of doing it the "wrong" way. Soldering a pre-crimped joint
seems to be OK from a joint strength POV.

>But I used to use crimped terminals sometimes - I've got nothing against
>them, just seldom had them to hand.

--

-Pip

On 23/08/2023 21:18, Stephen Packer wrote:
> On Wednesday, 23 August 2023 at 16:21:57 UTC+1, siwilson wrote:
>> On 23/08/2023 16:15, Stephen Packer wrote:
>>
>>>
>>> [1] Modern solder really is shit. When I started messing about with car
>>> and bike electrics the solder actually worked. You could take a (slightly)
>>> tarnished and oxidised wire and the acid flux core/lead solder would melt,
>>> clean the tarnishing and then wet the wire. These days it's so much harder.
>>> I know my soldering skills aren't what they were but I suspect the modern
>>> flux and solder doesn't help. Oh for the days of cancerous industrial
>>> compounds and workers dying in their early sixties...
>> https://www.ebay.co.uk/itm/225464766264 I believe is the same as old
>> stuff. I've still got loads left.
>
> HFM!!!
>
> £50 for a 500g^W 1lb roll.
>
> Still tempted to purchase but have bought a metre first.

https://www.ebay.co.uk/itm/384356386069

A 100g reel is doing pretty well so far for me, and I've made a few
electronics projects with 100 or so soldered joints on the board, plus a
few jack and DC power leads and the odd wire splice.

On 24/08/2023 21:16, Pipl wrote:
> On Wed, 23 Aug 2023 22:26:22 -0000 (UTC), wessie
> <willnotwork@tesco.net> wrote:
>
>> mount components or poorly etched tracks on the cheap & nasty bare boards
>> they sourced.
>
> We used to get whiskers between tracks when they were made, too. No
> solder resist on those boards. The quick fix for an unknown short was
> "the magic brush wipe". A good scrub with a flux cleaning brush would
> often cure that sort of thing.

Many years ago, I was on the team that built and ran SMIDSY in Robot
Wars. The control circuits were made up on vero. In the series where I
was on the team that appeared on telly, we had an issue where we
suddenly lost control - fortunately after two other robots had already
been put out, and to stop us getting wrecked by the house robots I asked
the other remaining team to put us in the pit. Back for diagnosis, I had
one of the controller boards and ran my thumbnail down the gaps between
the tracks, and a solder blob popped off. It had bridged between the
ground rail and something else, and had been there since the board had
been built so that explained some of the mysterious deactivations that
had plagued it.

On 27/08/2023 07:32, sweller wrote:
> Mark Olson wrote:
>
>> I'm [mis?]remembering that soldered connections on vehicle wiring[1]
>> are discouraged- it tends to concentrate stress, IIRC.
>
> I was told this and have stuck by it.
>
> This is, of course, nothing to do with the fact that my soldering is
> atrocious.

IIRC it's something to do with the solder wicking up the wire and making
it brittle and fatigue prone. And my soldering is crap too.