Crimped ferrules (?) on ends of 13A cables

[MM]

See http://www.littletyke.myzen.co.uk/crimped_ferrules.jpg

What is the correct name for them and where do I find them? I've
googled and amazoned, but there are so many different kinds I can't
see the wood for the trees.

I've always tinned the wire strands to (a) make it easier to fit them
into the screwed holder and (b) stop the strands from splaying when
tightening the screw.

The above cable is off an old Woolworths extension lead.

MM

[Andrew Mawson]

"MM" wrote in message news:fkovkbp98fn3ddg9b...@4ax.com...

"Bootlace Ferrules"

I prefer the ones that have a short plastic sleeve incorporated to act as
funnel and ensure no free strands escape.

http://www.ebay.co.uk/itm/Cable-Cord-End-Terminals-Single-Entry-Bootlace-Ferrules-0-25mm-16mm-/160882425181?var=&hash=item257556fd5d:m:mJapzTg_QmkQY_IAVL7gTuA

or the uninsulated ones:

http://www.ebay.co.uk/itm/100x-Uninsulated-Bootlace-Cord-End-Ferrule-Terminals-Crimps-Cable-0-5mm-16mm-/262431672828?var=&hash=item3d1a2589fc:m:mjFaCo1wJnDvci_ZNiYGz2A


Andrew

[Andy Burns]

MM wrote:

> See http://www.littletyke.myzen.co.uk/crimped_ferrules.jpg
> What is the correct name for them

uninsulated bootlace ferrules

> and where do I find them?

rs, cpc, farnell, rapid etc

> I've always tinned the wire strands to (a) make it easier to fit them
> into the screwed holder and (b) stop the strands from splaying when
> tightening the screw.

Not a good idea as the solder is soft and creeps under the pressure of
the screw terminal, loosening over time.

[Ian]

On 2016-06-02, MM <kyli...@yahoo.co.uk> wrote:
> See http://www.littletyke.myzen.co.uk/crimped_ferrules.jpg
>
> What is the correct name for them and where do I find them? I've
> googled and amazoned, but there are so many different kinds I can't
> see the wood for the trees.
>
> I've always tinned the wire strands to (a) make it easier to fit them
> into the screwed holder and (b) stop the strands from splaying when
> tightening the screw.

These are what you need (other suppliers available):

http://uk.farnell.com/multicomp/duce1515/ferrule-1-5mm-pk100/dp/9972099
http://uk.farnell.com/multicomp/duce1010/ferrule-1mm-pk100/dp/1269361
etc.

Pick the right size for the wire you've got.

You also need the proper crimp tool, e.g.:

http://uk.farnell.com/davico/dcer-510/crimp-tool-ratchet/dp/209181

Don't tin stranded wires for screw terminals, the solder flows under
pressure, leaving a poor contact.


--
Ian

"Tamahome!!!" - "Miaka!!!"

[Andy Burns]

Ian wrote:

> You also need the proper crimp tool

If you've already got a proper tool for crimp terminals, which isn't
suitable for ferrules, you could cut the contact part off, as per

<http://reprap.org/mediawiki/images/b/b0/Header_Crimp.jpg>

[tabb...@gmail.com]

On Thursday, 2 June 2016 08:52:35 UTC+1, Andy Burns wrote:

> MM wrote:

> > I've always tinned the wire strands to (a) make it easier to fit them
> > into the screwed holder and (b) stop the strands from splaying when
> > tightening the screw.
>
> Not a good idea as the solder is soft and creeps under the pressure of
> the screw terminal, loosening over time.

+1


NT

[The Natural Philosopher]

Then you didn't tighten it enough to start with.

Think of the solder as a mastic to fill the gaps between the copper, but
the copper makes the joint



--
Truth welcomes investigation because truth knows investigation will lead
to converts. It is deception that uses all the other techniques.

[Mike Tomlinson]

En el artículo <dra6u0...@mid.individual.net>, Andy Burns

<feb2017...@adslpipe.co.uk> escribió:

>Not a good idea as the solder is soft and creeps under the pressure of
>the screw terminal, loosening over time.

Resulting in this:

https://www.dropbox.com/s/fjc3xol5eyy6f06/DSC00015.JPG?dl=0

https://www.dropbox.com/s/3lcfzoe1lb683wz/DSC00018.JPG?dl=0

--
(\_/)
(='.'=) systemd: the Linux version of Windows 10
(")_(")

[MM]

On Thu, 2 Jun 2016 08:51:38 +0100, "Andrew Mawson"
<andrew@please_remove_me.mawson.org.uk> wrote:

>"MM" wrote in message news:fkovkbp98fn3ddg9b...@4ax.com...
>>
>>See http://www.littletyke.myzen.co.uk/crimped_ferrules.jpg
>>
>>What is the correct name for them and where do I find them? I've
>>googled and amazoned, but there are so many different kinds I can't
>>see the wood for the trees.
>>
>>I've always tinned the wire strands to (a) make it easier to fit them
>>into the screwed holder and (b) stop the strands from splaying when
>>tightening the screw.
>>
>>The above cable is off an old Woolworths extension lead.
>>
>>MM
>
>"Bootlace Ferrules"
>
>I prefer the ones that have a short plastic sleeve incorporated to act as
>funnel and ensure no free strands escape.
>
>http://www.ebay.co.uk/itm/Cable-Cord-End-Terminals-Single-Entry-Bootlace-Ferrules-0-25mm-16mm-/160882425181?var=&hash=item257556fd5d:m:mJapzTg_QmkQY_IAVL7gTuA

Those are nothing like the ones on the ends of the piece of cable I
removed from the extension block. The ones shown in my pic are very
short. Only about 7mm long.

>
>or the uninsulated ones:
>
>http://www.ebay.co.uk/itm/100x-Uninsulated-Bootlace-Cord-End-Ferrule-Terminals-Crimps-Cable-0-5mm-16mm-/262431672828?var=&hash=item3d1a2589fc:m:mjFaCo1wJnDvci_ZNiYGz2A

They also appear to be much longer than on the cables in my pic.
(Maybe the short kind in my pic are no longer available/used;
Woolworths has been defunct in Britain for several years now.)

MM

[MM]

On Thu, 2 Jun 2016 07:54:24 -0000 (UTC), Ian
<${send-direct-email-to-news1021-at-jusme-dot-com-if-you-must}@jusme.com>
wrote:

>On 2016-06-02, MM <kyli...@yahoo.co.uk> wrote:
>> See http://www.littletyke.myzen.co.uk/crimped_ferrules.jpg
>>
>> What is the correct name for them and where do I find them? I've
>> googled and amazoned, but there are so many different kinds I can't
>> see the wood for the trees.
>>
>> I've always tinned the wire strands to (a) make it easier to fit them
>> into the screwed holder and (b) stop the strands from splaying when
>> tightening the screw.
>
>These are what you need (other suppliers available):
>
>http://uk.farnell.com/multicomp/duce1515/ferrule-1-5mm-pk100/dp/9972099

But these look too long for the screwed post they're inserted into.
The bared ends of the wires are about 7mm in length, whereas these
uninsulated ferrules from e.g. Farnell look longer than that. Or is it
permitted to trim off any surplus length with sidecutters?

MM

[MM]

On Thu, 2 Jun 2016 09:04:23 +0100, Andy Burns

Ah, the *right*-hand side of these seem to be much more like the ones
on my cable (before being crimped on).

MM

[Andy Burns]

MM wrote:

> Ian wrote:
>
>> http://uk.farnell.com/multicomp/duce1515/ferrule-1-5mm-pk100/dp/9972099
>
> But these look too long for the screwed post they're inserted into.
> The bared ends of the wires are about 7mm in length, whereas these
> uninsulated ferrules from e.g. Farnell look longer than that. Or is it
> permitted to trim off any surplus length with sidecutters?

Yes, they're only tin-plated copper, so cut easily.

[Tricky Dicky]

In the days when appliances did not come with a moulded plug the tinned wires you used to get was more for testing purposes and you were usually advised by the manufacturer to trim the wires down removing the tinned ends for the reasons stated earlier, however not all RTFM. The tinned wires were usually too long to fit comfortably in a plug anyway. Bare wire or ferrules are the recommended means.

Richard

[Capitol]

The Natural Philosopher wrote:
> On 02/06/16 08:52, Andy Burns wrote:
>> MM wrote:
>>
>>> See http://www.littletyke.myzen.co.uk/crimped_ferrules.jpg
>>> What is the correct name for them
>>
>> uninsulated bootlace ferrules
>>
>>> and where do I find them?
>>
>> rs, cpc, farnell, rapid etc
>>
>>> I've always tinned the wire strands to (a) make it easier to fit them
>>> into the screwed holder and (b) stop the strands from splaying when
>>> tightening the screw.
>>
>> Not a good idea as the solder is soft and creeps under the pressure of
>> the screw terminal, loosening over time.
>>
> Then you didn't tighten it enough to start with.
>
> Think of the solder as a mastic to fill the gaps between the copper,
> but the copper makes the joint
>
>
>

+1

[Adam Funk]

On 2016-06-02, Andy Burns wrote:

> MM wrote:

>> I've always tinned the wire strands to (a) make it easier to fit them
>> into the screwed holder and (b) stop the strands from splaying when
>> tightening the screw.
>
> Not a good idea as the solder is soft and creeps under the pressure of
> the screw terminal, loosening over time.

ISTR that is (or used to be) common practice with speaker wires, but
they usually go in sprung rather than screwed terminals (& obviously
don't carry much current).

[Syd Rumpo]

Something from here would probably fit...

http://uk.farnell.com/webapp/wcs/stores/servlet/Search?catalogId=15001&langId=44&storeId=10151&categoryId=700000004976&st=crimps&beginIndex=1&showResults=true&aa=true&sf=502&pf=110338670

And I'd agree with not tinning the wires. I was taught to - if there's
room - double the earth wire back on itself so in the event of a
pull-out it would be the last to be disconnected. Can't say I bother
nowadays.

Cheers
--
Syd

[Theo]

The Natural Philosopher <t...@invalid.invalid> wrote:
> Then you didn't tighten it enough to start with.
>
> Think of the solder as a mastic to fill the gaps between the copper, but
> the copper makes the joint

The other reason not to tin is it provides a fatigue point at the exit from
the solder lump. That's not much of a problem in household wiring, but it
is in something that sees vibration - like a power tool or a car.

Theo

[The Natural Philosopher]

On 02/06/16 11:34, pamela wrote:

> On 09:57 2 Jun 2016, Mike Tomlinson wrote:
>
>> En el artículo <dra6u0...@mid.individual.net>, Andy Burns
>> <feb2017...@adslpipe.co.uk> escribió:
>>
>>> Not a good idea as the solder is soft and creeps under the
>>> pressure of the screw terminal, loosening over time.
>>
>> Resulting in this:
>>
>> https://www.dropbox.com/s/fjc3xol5eyy6f06/DSC00015.JPG?dl=0
>>
>> https://www.dropbox.com/s/3lcfzoe1lb683wz/DSC00018.JPG?dl=0
>

> Gulp!
>
You can clearly see the live hasn't been screwed down hard enough
compared to the others


--
How fortunate for governments that the people they administer don't think.

Adolf Hitler

[The Natural Philosopher]

Absolutely.

First rule of Being an Apperntice in avionics.

No Soldered stranded wire joint shall be mechanically unsupported except
for the solder.

Solid was half allowed.

Crimps were ultimately preferred - the data on crimping came in around
that time (1969) where it was found to show a lower failure rate.

The Proper Way was to solder then use a sleeve as local support and then
tie the wire down elsewhere.

Crimps with integral sleeves came in a bit later on, and were a lot
faster in production.

Heatshrink was even later

> Theo

[Mike Tomlinson]

En el artículo <nip38b$skh$1...@news.albasani.net>, The Natural Philosopher
<t...@invalid.invalid> escribió:

>You can clearly see the live hasn't been screwed down hard enough
>compared to the others

Actually, I would say it's a very clear illustration of how the solder
has crept under the neutral and earth screws.

Another problem with soldering tails is that it makes it very easy to
pinch them off by tightening the screw too much. Think of how easy it
is to pinch a bit of solder off a reel with your thumbnail. Now try
doing that with stripped copper wire.

I used to tin my wire tails; I don't any more. If it's possible to
strip a longer length of insulation back, double the stripped end over
and insert that in the plug terminal, I do that instead.

[The Natural Philosopher]

On 02/06/16 12:31, Mike Tomlinson wrote:
> En el artículo <nip38b$skh$1...@news.albasani.net>, The Natural Philosopher
> <t...@invalid.invalid> escribió:
>
>> You can clearly see the live hasn't been screwed down hard enough
>> compared to the others
>
> Actually, I would say it's a very clear illustration of how the solder
> has crept under the neutral and earth screws.

Which is why the neutral has arced, not the live, Obviously!

Dear oh dear.

>
> Another problem with soldering tails is that it makes it very easy to
> pinch them off by tightening the screw too much. Think of how easy it
> is to pinch a bit of solder off a reel with your thumbnail. Now try
> doing that with stripped copper wire.
>

Now try doing that with tinned copper wire.

> I used to tin my wire tails; I don't any more. If it's possible to
> strip a longer length of insulation back, double the stripped end over
> and insert that in the plug terminal, I do that instead.
>

That's *a* way of doing things


--
“But what a weak barrier is truth when it stands in the way of an
hypothesis!”

Mary Wollstonecraft

[Andy Burns]

pamela wrote:

> The Natural Philosopher wrote:
>
>> Which is why the neutral has arced, not the live, Obviously!
>

> It's the live.

Check if local college offers evening classes in sarcasm awareness.

[The Natural Philosopher]

On 02/06/16 13:28, pamela wrote:

> On 12:43 2 Jun 2016, The Natural Philosopher wrote:
>
>> On 02/06/16 12:31, Mike Tomlinson wrote:

>>> En el artículo <nip38b$skh$1...@news.albasani.net>, The Natural
>>> Philosopher <t...@invalid.invalid> escribió:

>>>
>>>> You can clearly see the live hasn't been screwed down hard
>>>> enough compared to the others
>>>
>>> Actually, I would say it's a very clear illustration of how the
>>> solder has crept under the neutral and earth screws.
>>
>>
>> Which is why the neutral has arced, not the live, Obviously!
>>
>> Dear oh dear.
>

> It's the live.
>

Sarcasm pam.


His thesis is disproved by the effect that has happened.

Yet he blandly advances it as if it made sense.


--
“Some people like to travel by train because it combines the slowness of
a car with the cramped public exposure of 
an airplane.”

Dennis Miller

[The Natural Philosopher]

;-)

[Graham.]

pamela <inv...@nospam.com> Wrote in message:

> On 09:57 2 Jun 2016, Mike Tomlinson wrote:
>

>> En el artículo <dra6u0...@mid.individual.net>, Andy Burns
>> <feb2017...@adslpipe.co.uk> escribió:
>>
>>>Not a good idea as the solder is soft and creeps under the
>>>pressure of the screw terminal, loosening over time.
>>
>> Resulting in this:
>>
>> https://www.dropbox.com/s/fjc3xol5eyy6f06/DSC00015.JPG?dl=0
>>
>> https://www.dropbox.com/s/3lcfzoe1lb683wz/DSC00018.JPG?dl=0
>

> Gulp!
>

With terminals like those, I find that wires terminated with
bootlace ferrules can need an extra half turn after a few months.
Bare wires doubled over in the time -honored way seem to fare
best, is that a no-no now?
--

%Profound_observation%


----Android NewsGroup Reader----
http://usenet.sinaapp.com/

[The Natural Philosopher]

On 02/06/16 14:14, pamela wrote:

> On 13:59 2 Jun 2016, The Natural Philosopher wrote:
>
>> On 02/06/16 13:28, pamela wrote:
>>> On 12:43 2 Jun 2016, The Natural Philosopher wrote:
>>>
>>>> On 02/06/16 12:31, Mike Tomlinson wrote:

>>>>> En el artículo <nip38b$skh$1...@news.albasani.net>, The Natural
>>>>> Philosopher <t...@invalid.invalid> escribió:

>>>>>
>>>>>> You can clearly see the live hasn't been screwed down hard
>>>>>> enough compared to the others
>>>>>
>>>>> Actually, I would say it's a very clear illustration of how the
>>>>> solder has crept under the neutral and earth screws.
>>>>
>>>>
>>>> Which is why the neutral has arced, not the live, Obviously!
>>>>
>>>> Dear oh dear.
>>>
>>> It's the live.
>>>
>>
>> Sarcasm pam.
>

> It was a bit too deadpan for me!

>
>> His thesis is disproved by the effect that has happened.
>>
>> Yet he blandly advances it as if it made sense.
>

> Dunno.
>
> Aren't there two points?
>
> One: a loose live screw caused arcing.
> Two: tight earth and neutral screws caused solder creep.
>
There was a third point. If there is solder, tighten down hard. The
solder creeps but the joint is tight

I.e teh failure was due to lack of tightening as shown by the ABSENCE of
solder creep on the live wire.

Arcing is down to bad torque, not solder.

I've had plenty of plugs with bare wires that have arced as well.



--
Outside of a dog, a book is a man's best friend. Inside of a dog it's
too dark to read.

Groucho Marx

[T i m]

On Thu, 02 Jun 2016 14:09:45 +0100, pamela <inv...@nospam.com> wrote:

>What's the point of being sarcastic about the colour of the lead?
>
>*puzzled*


It's a bloke thing. ;-)

(But it wasn't about the colour, it was about the issue).

There is a possibility the live could have been at a disadvantage
because (over the neutral, although they would both be carrying the
same current) because of any resistance of the fuse causing localised
heating *and* lack of heat sink to the pin (and socket) for the screw
terminal.

I will / do tin stranded leads where the situation suits and I have
tinned them (and still will now and again) when I had fitted them in a
13 plug top and have *never* (in ~50 years) *ever* had any issues
because of doing so.

Depending on the quality of the plug, the screws in the pin can either
have a strand friendly ball end or a fairly flat / sharp face that can
easily slice though a few strands (and where a ferrule / tinning can
specifically help).

That's why many (often better quality) screw terminal blocks have a
small steel tongue under the screw to prevent fine strands being cut /
missed out.

Cheers, T i m

[Dave Plowman (News)]

In article <poe0lb5dkek0fkufk...@4ax.com>,

T i m <ne...@spaced.me.uk> wrote:
> Depending on the quality of the plug, the screws in the pin can either
> have a strand friendly ball end or a fairly flat / sharp face that can
> easily slice though a few strands (and where a ferrule / tinning can
> specifically help).

I've never ever had a screw terminal slice through a few strands. More
likely is they were partially cut when stripping the insulation. All to
easy, if not using the correct tool.

> That's why many (often better quality) screw terminal blocks have a
> small steel tongue under the screw to prevent fine strands being cut /
> missed out.

More to allow a wide range of cable sizes to be used. Not needed on a
mains plug.

--
*Great groups from little icons grow *

Dave Plowman da...@davenoise.co.uk London SW
To e-mail, change noise into sound.

[T i m]

On Thu, 02 Jun 2016 15:11:18 +0100, "Dave Plowman (News)"
<da...@davenoise.co.uk> wrote:

>In article <poe0lb5dkek0fkufk...@4ax.com>,
> T i m <ne...@spaced.me.uk> wrote:
>> Depending on the quality of the plug, the screws in the pin can either
>> have a strand friendly ball end or a fairly flat / sharp face that can
>> easily slice though a few strands (and where a ferrule / tinning can
>> specifically help).
>
>I've never ever had a screw terminal slice through a few strands.

You are either very lucky, only use quality components or don't use
very fine / flexy cables. ;-)

> More
>likely is they were partially cut when stripping the insulation.

Never.

> All to
>easy, if not using the correct tool.

Quite. ;-)

>
>> That's why many (often better quality) screw terminal blocks have a
>> small steel tongue under the screw to prevent fine strands being cut /
>> missed out.
>
>More to allow a wide range of cable sizes to be used.

'As well' I'd say (unless you can find something that defines the role
formally etc). I say that because I have seen (and use) some
electronics where the aforementioned 'protected' screw terminal wasn't
really big enough for the sort of gauge wire you might typically use
with it (like the chassis mounted SMPSUs we have used). So, had the
terminal been 'big' and you wanted to use a smaller wire (... than
would be sufficiently rated to match the output of the PSU for
example), your explanation would have been more likely (in that case
etc). They also come into their own when attaching more than one of a
similar diameter cable (side by side for example, rather than twisting
the two together and putting them in as one or trying to put them in
side by side without twisting and risking losing some strands).

>Not needed on a
>mains plug.

Hmm, I'd say I might like such a thing on a mains plug as I always
feel more confident when using connectors with them than without. With
you just apply a broad clamping force whereas without, you *do* risk
cutting through the conductors (as I have done more than once). That
said, mains flex doesn't normally come with as many strands as some
'high flex' cables so they wouldn't generally be as much of an issue.

It's a similar idea with the Mk (and possibly others) round terminals
and washer protected 'nuts' (that didn't rotate on the wire as you did
up the 'nut') and so that cable was 'only' clamped, no risk of a
conductor being sheared.

Cheers, T i m

[dennis@home]

On 02/06/2016 09:57, Mike Tomlinson wrote:
> En el artículo <dra6u0...@mid.individual.net>, Andy Burns
> <feb2017...@adslpipe.co.uk> escribió:
>
>> Not a good idea as the solder is soft and creeps under the pressure of
>> the screw terminal, loosening over time.
>
> Resulting in this:
>
> https://www.dropbox.com/s/fjc3xol5eyy6f06/DSC00015.JPG?dl=0

The neutral is too long, the earth is too short.
I always try and make it so the earth is the last thing that can pull
out if the cord grip fails to do its job.

[dennis@home]

On 02/06/2016 12:43, The Natural Philosopher wrote:
> On 02/06/16 12:31, Mike Tomlinson wrote:
>> En el artículo <nip38b$skh$1...@news.albasani.net>, The Natural Philosopher
>> <t...@invalid.invalid> escribió:
>>
>>> You can clearly see the live hasn't been screwed down hard enough
>>> compared to the others
>>
>> Actually, I would say it's a very clear illustration of how the solder
>> has crept under the neutral and earth screws.
>
>
> Which is why the neutral has arced, not the live, Obviously!

For the benefit of Brian..

Its a 13A plug with one of the wires burnt.

The neutral is the blue wire on the left that shows no sign of burning
or arcing.
The live is the brown one going to the fuse on the right that is burnt
and shows signs of arcing.

> Dear oh dear.

[dennis@home]

On 02/06/2016 14:09, pamela wrote:
> On 13:48 2 Jun 2016, Andy Burns wrote:
>

> What's the point of being sarcastic about the colour of the lead?
>
> *puzzled*
>

Its always a joke when TNP gets something wrong, you should have noticed
that from previous posts.

[dennis@home]

On 02/06/2016 14:14, pamela wrote:


> Aren't there two points?
>
> One: a loose live screw caused arcing.
> Two: tight earth and neutral screws caused solder creep.
>

Solder creep is what causes the screw to loosen over time which is why
you get the arcing.
You can see the indentations in the wire/solder where the screws were
tightened at one time.
The solder then moves out under the pressure from the screw which
reduces the pressure allowing the screw to loosen under vibration and/or
heat cycles.
Its why you use crimps if you can unless you want stuff to fail sooner.

[dennis@home]

On 02/06/2016 14:46, Graham. wrote:


> With terminals like those, I find that wires terminated with
> bootlace ferrules can need an extra half turn after a few months.
> Bare wires doubled over in the time -honored way seem to fare
> best, is that a no-no now?
>

No fold should be best as long as the terminal is the correct size for
the wire.

[The Natural Philosopher]

Oh dear dennis, The whole thing has passed over your head even higher
than pamelas.



--
Those who want slavery should have the grace to name it by its proper
name. They must face the full meaning of that which they are advocating
or condoning; the full, exact, specific meaning of collectivism, of its
logical implications, of the principles upon which it is based, and of
the ultimate consequences to which these principles will lead. They must
face it, then decide whether this is what they want or not.

Ayn Rand.

[The Natural Philosopher]

On 02/06/16 17:00, dennis@home wrote:
> On 02/06/2016 14:14, pamela wrote:
>
>
>> Aren't there two points?
>>
>> One: a loose live screw caused arcing.
>> Two: tight earth and neutral screws caused solder creep.
>>
>
> Solder creep is what causes the screw to loosen over time which is why
> you get the arcing.

No it isn't.

> You can see the indentations in the wire/solder where the screws were
> tightened at one time.

Only in the ones that HAVENT arced

> The solder then moves out under the pressure from the screw which
> reduces the pressure allowing the screw to loosen under vibration and/or
> heat cycles.
> Its why you use crimps if you can unless you want stuff to fail sooner.

The only crimps you use dennis are in your pubic hair.

[dennis@home]

On 02/06/2016 17:30, The Natural Philosopher wrote:
> On 02/06/16 17:00, dennis@home wrote:
>> On 02/06/2016 14:14, pamela wrote:
>>
>>
>>> Aren't there two points?
>>>
>>> One: a loose live screw caused arcing.
>>> Two: tight earth and neutral screws caused solder creep.
>>>
>>
>> Solder creep is what causes the screw to loosen over time which is why
>> you get the arcing.
>
> No it isn't.

Of course it is.

>
>> You can see the indentations in the wire/solder where the screws were
>> tightened at one time.
>
> Only in the ones that HAVENT arced

Everyone can look at the photo and see you are lying!
There are screw indents in all the wires.
Maybe you should have gone to specsavers?

[The Natural Philosopher]

On 02/06/16 17:41, dennis@home wrote:
> On 02/06/2016 17:30, The Natural Philosopher wrote:
>> On 02/06/16 17:00, dennis@home wrote:
>>> On 02/06/2016 14:14, pamela wrote:
>>>
>>>
>>>> Aren't there two points?
>>>>
>>>> One: a loose live screw caused arcing.
>>>> Two: tight earth and neutral screws caused solder creep.
>>>>
>>>
>>> Solder creep is what causes the screw to loosen over time which is why
>>> you get the arcing.
>>
>> No it isn't.
>
> Of course it is.
>
>>
>>> You can see the indentations in the wire/solder where the screws were
>>> tightened at one time.
>>
>> Only in the ones that HAVENT arced
>
> Everyone can look at the photo and see you are lying!
> There are screw indents in all the wires.
> Maybe you should have gone to specsavers?
>

And the smallest indent is in the wire that arced, because it wasnt
tightened down

Maybe you should have gone to specsavers?
>>
>>> The solder then moves out under the pressure from the screw which
>>> reduces the pressure allowing the screw to loosen under vibration and/or
>>> heat cycles.
>>> Its why you use crimps if you can unless you want stuff to fail sooner.
>>
>> The only crimps you use dennis are in your pubic hair.
>>
>

[Harry Bloomfield]

dennis@home a écrit :

> Solder creep is what causes the screw to loosen over time which is why you
> get the arcing.
> You can see the indentations in the wire/solder where the screws were
> tightened at one time.
> The solder then moves out under the pressure from the screw which reduces the
> pressure allowing the screw to loosen under vibration and/or heat cycles.
> Its why you use crimps if you can unless you want stuff to fail sooner.

+1...

I used to sometimes tin the ends, but having seen the results of solder
creep numerous times, I stopped doing it. No amount of tightening the
terminal screw can apply enough pressure to avoid the problem. The
solder creeps, the terminal becomes loose, the lead oxidises and it
over heats sometimes melting the solder.

[Harry Bloomfield]

The Natural Philosopher a écrit :

> And the smallest indent is in the wire that arced, because it wasnt tightened
> down

I suggest the difference in the depth of indent is due to the solder
melting and flowing out of the live copper.

[The Natural Philosopher]

make up whatever stories you like. You obviously cant solder. All the
copper should be as much in contact with itself as without solder. thats
only supposed to fill the gaps.


--
Religion is regarded by the common people as true, by the wise as
foolish, and by the rulers as useful.

(Seneca the Younger, 65 AD)

[dennis@home]

Careful the TNP has lost it and will throw insults at you for suggesting
what actually happens.

[Harry Bloomfield]

The Natural Philosopher a écrit :

> make up whatever stories you like. You obviously cant solder. All the copper
> should be as much in contact with itself as without solder. thats only
> supposed to fill the gaps.

I very obviously can solder...

Tinning the flex will hold the stands of the flex in a certain position
as the screw is tightened. As the solder migrates gradually under the
screw's pressure the terminal can then become loose. Just tinning the
flex can be difficult to achieve, without their being some bulk of
solder involved.

As said, I did once beleive that tinning flex was best practise, but
not now having seen lots of evidence to the contrary. Solder with a
compression connection, is an absolute no, no.

[Capitol]

Jethro_uk wrote:

> On Thu, 02 Jun 2016 11:58:42 +0100, The Natural Philosopher wrote:
>
>
>> On 02/06/16 11:35, Theo wrote:
>>

>>> [quoted text muted]

>>>
>> Absolutely.
>>
>> First rule of Being an Apperntice in avionics.
>>

> A couple of years ago I was at Cosford Air Museum. They had just taken
> delivery of a Nimrod, and had removed the wings to transport it. It was
> plonked outside one of the hangers.
>
> The removed wings exposed the spaghetti of wiring - all cut. It was
> heartbreaking in a way.
>
> Hundreds of wires - all white. I presume that was some part of making it
> difficult to easily reverse engineer.
>
> It was interesting to think that at sometime someone would have known
> what each wire did, and where it went.
>
Each end of the wire would have been numbered. normal practice is
only one colour of wire for a given current/voltage rating.

[Capitol]

Agreed.

[Capitol]

Criming is good on stranded wires subject to vibration.
However, you are always at the mercy of the crimp tool and wire
behaviour. I have had many more crimp failures than screw terminal
failures over the years I have been wiring equipments. Crimping is
generally very poor on reliability with solid wires if there are
temperature changes. Hence the popularity of wire wrap.

[dennis@home]

On 02/06/2016 21:19, Capitol wrote:
8<

> Criming is good on stranded wires subject to vibration. However,
> you are always at the mercy of the crimp tool and wire behaviour. I have
> had many more crimp failures than screw terminal failures over the years
> I have been wiring equipments. Crimping is generally very poor on
> reliability with solid wires if there are temperature changes. Hence the
> popularity of wire wrap.

Wire wrap forms a cold weld which is gas tight, if its done with correct
tool and wire.

[Graham.]

So what is the correct size wire for a BS1363 rewireable plug?
Even with wires as thick as these
https://www.dropbox.com/s/fjc3xol5eyy6f06/DSC00015.JPG?dl=0
I find folding it back on itself fills the terminal hole more fully,
and the result seems to me to be more secure.

I prefer the MK type plugs with knurled screws. With those I don't
fold the wires.


--

Graham.

%Profound_observation%

[Mike Tomlinson]

En el artículo <nip63n$2hg$1...@news.albasani.net>, The Natural Philosopher
<t...@invalid.invalid> escribió:

>Which is why the neutral has arced, not the live, Obviously!

The same current flows through the neutral wire, so either could have
arced. You're getting more and more like D i m.

The whole point is that tinning wire ends before putting a plug on is
deprecated, as it leads to solder creep and bad/arcing contacts.

You also conveniently ignored the point that tinning converts the wire
end into a single soft block of metal which is easy to pinch off if the
screw is overtightened.

Crimped ends, being harder metal, don't creep under the screw pressure.

>Dear oh dear.

Quite.

>That's *a* way of doing things

Doubling the wore over maximises the surface contact area between the
wire and the plug body, reducing the likelihood of a high resistance
connection developing.

I took the photos of the plug in question. That alone was evidence
enough for me that tinning wire ends isn't a good idea and I haven't
done it since.

http://reprap.org/wiki/Wire_termination_for_screw_terminals

--
(\_/)
(='.'=) systemd: the Linux version of Windows 10
(")_(")

[The Natural Philosopher]

On 03/06/16 09:25, Mike Tomlinson wrote:
> You also conveniently ignored the point that tinning converts the wire
> end into a single soft block of metal

What? I really believe your brain has turned to MUSH.

what happened to all those copper wires?

magically become part of some new alloy?

MO wonder people want to stay in the EU.

No one has a brain left after 40 years of socialist state education.


--
To ban Christmas, simply give turkeys the vote.

[T i m]

On Fri, 3 Jun 2016 09:29:31 +0100, The Natural Philosopher
<t...@invalid.invalid> wrote:

>On 03/06/16 09:25, Mike Tomlinson wrote:
>> You also conveniently ignored the point that tinning converts the wire
>> end into a single soft block of metal
>
>What? I really believe your brain has turned to MUSH.

On this we agree. The problem with people like Tomlinson is they are
never wrong (in their own heads).

>
>what happened to all those copper wires?
>
>magically become part of some new alloy?

Quite. He's talking complete and utter BS.

If you tin some stranded wire you are just binding the (copper)
together with another conductor (tin / lead) and as long as you don't
go OTT with the solder (where you end up with surplus solder on / over
the strands) then doing so can have little mechanical impact over the
original copper strands, other than keeping them together better.

If you push (particularly fine) stranded wire into a conventional
screw type terminal (chock block / 13A plug pin) and without twisting
the strands there is a very good chance several things could happen:

1) Some stands may not make it into the connector.
2) Some strands won't get clamped by the screw (and will go up the
sides of the screw).
3) Because the stands are fine they can be easily cut by the rotating
end of the screw as it clamps.

The second option is to twist the conductors and assuming the twist
stays together as you tighten the screw, could be better than not
twisting.

However, a better solution might be to twist and tin, (and even twist,
double over and tin if the wire is small enough) and that way you
don't suffer any of the issues noted above.

I have been doing just that for nearly 50 years and never had any
issues. Maybe I know how to properly tin a cable and how to properly
tighten a screw and Tomlinson doesn't. ;-(

Cheers, T i m

[Dave Plowman (News)]

In article <575099d2$0$41641$b1db1813$62b0...@news.astraweb.com>,

Odd that pretty well every terminal you find on a car, from Trabant to
Bentley, is crimped.

Of course I'd not expect crapitol to know as with everything else it is
possible to crimp something badly.

--
*CAN AN ATHEIST GET INSURANCE AGAINST ACTS OF GOD?

[Capitol]

Dave Plowman (News) wrote:
> In article<575099d2$0$41641$b1db1813$62b0...@news.astraweb.com>,
> dennis@home<den...@nowhere.invalid> wrote:
>
>> On 02/06/2016 21:19, Capitol wrote:
>> 8<
>>
>
>>> Criming is good on stranded wires subject to vibration.
>>> However, you are always at the mercy of the crimp tool and wire
>>> behaviour. I have had many more crimp failures than screw terminal
>>> failures over the years I have been wiring equipments. Crimping is
>>> generally very poor on reliability with solid wires if there are
>>> temperature changes. Hence the popularity of wire wrap.
>>>
>
>> Wire wrap forms a cold weld which is gas tight, if its done with correct
>> tool and wire.
>>
> Odd that pretty well every terminal you find on a car, from Trabant to
> Bentley, is crimped.
>
> Of course I'd not expect crapitol to know as with everything else it is
> possible to crimp something badly.
>
>

How much manufacturing experience do you have? None?

[The Natural Philosopher]

Hellofa lot here.

Aerospace and commercial electrical and electronics.

I will repeat what I said elsewhere. Given the cost constraints on
making a good soldered,supported, sleeved joint in a *car*, crimping or
IDC is really the only viable way to make up mass produced looms at
sensible costs. That doesn't mean it's the best.

However cars don't usually die at the roadside from bad joints, so its
obviously *good enough*.

wire wrap and IDC is however deemed to be better *electrically* but that
doesn't take into account mechanical strength.

Soldering is almost never used for wring because its a difficult way to
connect wires to terminals or plugs and sockets on a production line.


--
"Women actually are capable of being far more than the feminists will
let them."

[Andrew Gabriel]

In article <niorkr$df7$1...@news.albasani.net>,
The Natural Philosopher <t...@invalid.invalid> writes:
> On 02/06/16 08:52, Andy Burns wrote:
>> MM wrote:
>>
>>> See http://www.littletyke.myzen.co.uk/crimped_ferrules.jpg
>>> What is the correct name for them
>>
>> uninsulated bootlace ferrules
>>
>>> and where do I find them?
>>
>> rs, cpc, farnell, rapid etc
>>
>>> I've always tinned the wire strands to (a) make it easier to fit them
>>> into the screwed holder and (b) stop the strands from splaying when
>>> tightening the screw.

>>
>> Not a good idea as the solder is soft and creeps under the pressure of
>> the screw terminal, loosening over time.
>>

> Then you didn't tighten it enough to start with.
>
> Think of the solder as a mastic to fill the gaps between the copper, but
> the copper makes the joint

It's never permitted to do this because the solder creeps over time
under pressure and contact pressure is lost, causing the connection
to then overheat.

--
Andrew Gabriel
[email address is not usable -- followup in the newsgroup]

[MM]

On Fri, 3 Jun 2016 09:25:58 +0100, Mike Tomlinson <mi...@jasper.org.uk>
wrote:

>http://reprap.org/wiki/Wire_termination_for_screw_terminals

As I understand it (e.g. the use of the word "deprecated"), tinning
*used* to be the recommendation?

MM

[MM]

On Fri, 3 Jun 2016 09:25:58 +0100, Mike Tomlinson <mi...@jasper.org.uk>
wrote:

>http://reprap.org/wiki/Wire_termination_for_screw_terminals

Also, this last recommendation in that article...

"Thirdly if using pre-tinned wire ends, the easy fix for the problem
(if you don't want to cut and strip) is to very gently torque up the
screw on the main power and heater wires after some hundred hours of
use. After a few times all the solder that can yield has flowed out of
the way and you have a good copper to brass mechanical contact. You do
not want to over tighten the screws and you also don't want to loosen
them when doing this maintenance, just a careful torquing it up to
take up the slack without repositioning it in a new orientation."

...seems totally fine.

And what bog-standard 3-pin 13A plugs (e.g. Wilko, Tesco, Asda) have
tongues in the screwed posts? I don't recall ever seeing them.

MM

[MM]

On Fri, 03 Jun 2016 10:15:10 +0100, T i m <ne...@spaced.me.uk> wrote:

>If you tin some stranded wire you are just binding the (copper)
>together with another conductor (tin / lead) and as long as you don't
>go OTT with the solder (where you end up with surplus solder on / over
>the strands) then doing so can have little mechanical impact over the
>original copper strands, other than keeping them together better.

I tin the wires exactly for that purpose, i.e. to keep the strands
together while the end is inserted into the screwed post. It also
makes for a very neat job, in my opinion. Note that I said *TIN*. That
doesn't mean putting a large blob of solder on the end! Less is more,
as they say.

>If you push (particularly fine) stranded wire into a conventional
>screw type terminal (chock block / 13A plug pin) and without twisting
>the strands there is a very good chance several things could happen:
>
>1) Some stands may not make it into the connector.
>2) Some strands won't get clamped by the screw (and will go up the
>sides of the screw).
>3) Because the stands are fine they can be easily cut by the rotating
>end of the screw as it clamps.
>
>The second option is to twist the conductors and assuming the twist
>stays together as you tighten the screw, could be better than not
>twisting.
>
>However, a better solution might be to twist and tin, (and even twist,
>double over and tin if the wire is small enough) and that way you
>don't suffer any of the issues noted above.

Yep, twist then tin is what I do.

>I have been doing just that for nearly 50 years and never had any
>issues. Maybe I know how to properly tin a cable and how to properly
>tighten a screw and Tomlinson doesn't. ;-(

I served 7 years as an apprentice motor fitter so I know a bit about
over-tightening screws or nuts.

You get a feel for how tight is tight after 60 years.

MM

[Andy Burns]

MM wrote:

> "Thirdly if using pre-tinned wire ends, the easy fix for the problem
> (if you don't want to cut and strip) is to very gently torque up the
> screw on the main power and heater wires after some hundred hours of
> use. After a few times all the solder that can yield has flowed out of
> the way and you have a good copper to brass mechanical contact. You do
> not want to over tighten the screws and you also don't want to loosen
> them when doing this maintenance, just a careful torquing it up to
> take up the slack without repositioning it in a new orientation."
>
> ...seems totally fine.

But does the average person, after fitting a 13A plug, go back several
times each after a few hundred hours and re-tighten it?

[Mike Tomlinson]

En el artículo <5su4lb5a8cip6723k...@4ax.com>, MM
<kyli...@yahoo.co.uk> escribió:

> the easy fix for the problem
>(if you don't want to cut and strip) is to very gently torque up the
>screw on the main power and heater wires after some hundred hours of
>use.

Realistically, no one is going to do that for domestic 13A plugs and
sockets, are they, though?

>And what bog-standard 3-pin 13A plugs (e.g. Wilko, Tesco, Asda) have
>tongues in the screwed posts? I don't recall ever seeing them.

Me neither (although I have seen them elsewhere, e.g. in PCB-mount
terminal strips). The closest equivalent is the MK Safetyplug which, as
another poster said, has a washer around the fixing nut so it clamps the
wire end without adding any twisting stress.

The thing about 13A 3-pin plugs having tongues is just D i m 's usual
bollocks.

[T i m]

On Sat, 04 Jun 2016 08:05:32 +0100, MM <kyli...@yahoo.co.uk> wrote:

>On Fri, 03 Jun 2016 10:15:10 +0100, T i m <ne...@spaced.me.uk> wrote:
>
>>If you tin some stranded wire you are just binding the (copper)
>>together with another conductor (tin / lead) and as long as you don't
>>go OTT with the solder (where you end up with surplus solder on / over
>>the strands) then doing so can have little mechanical impact over the
>>original copper strands, other than keeping them together better.
>
>I tin the wires exactly for that purpose, i.e. to keep the strands
>together while the end is inserted into the screwed post. It also
>makes for a very neat job, in my opinion. Note that I said *TIN*. That
>doesn't mean putting a large blob of solder on the end! Less is more,
>as they say.

Quite. And that may be the difference between those who can (and have
done so successfully for many many years) and those who end up with
stuff melted. ;-)

>
>>If you push (particularly fine) stranded wire into a conventional
>>screw type terminal (chock block / 13A plug pin) and without twisting
>>the strands there is a very good chance several things could happen:
>>
>>1) Some stands may not make it into the connector.
>>2) Some strands won't get clamped by the screw (and will go up the
>>sides of the screw).
>>3) Because the stands are fine they can be easily cut by the rotating
>>end of the screw as it clamps.
>>
>>The second option is to twist the conductors and assuming the twist
>>stays together as you tighten the screw, could be better than not
>>twisting.
>>
>>However, a better solution might be to twist and tin, (and even twist,
>>double over and tin if the wire is small enough) and that way you
>>don't suffer any of the issues noted above.
>
>Yep, twist then tin is what I do.

It seems to work eh. Can you *ever* remember having a problem after
wiring something using that process?

>
>>I have been doing just that for nearly 50 years and never had any
>>issues. Maybe I know how to properly tin a cable and how to properly
>>tighten a screw and Tomlinson doesn't. ;-(
>
>I served 7 years as an apprentice motor fitter so I know a bit about
>over-tightening screws or nuts.

And, (if not under tightening or using a torque wrench) there is a
definite 'feel' to this sort of thing that is easy to assume with
others.

>
>You get a feel for how tight is tight after 60 years.

Indeed. ;-)

A couple of times I've assisted people (over the phone) doing what I
would consider very basic tasks (like torquing down a cylinder head or
replacing an alternator) that have ended in tears (for them, not me)
because they don't have 'the feel'. The two instances I am thinking
of, one incorrectly read the torque wrench and the engine stud snapped
before the wrench clicked (when those with the feel might have
suspected something wasn't right) and similar with the guy changing
the alternator, stripping the thread on the tension bracket.

In fact, I've nearly stopped asking / allowing people to help me do
stuff because of how often something get's lost or broken (of mine)
whilst they are doing so, or just not doing it to my standards.

I was with BT 5 years and when I left my apprenticeship - soldering
test piece was still in the display cabinet as no one else had managed
100/100 whilst I was there. I found it quite easy whilst others
obviously struggled ... like I would if I was plastering a wall or
trying to program to fix something on Linux (or any other OS of
course). Everyone to their own etc. ;-)

Cheers, T i m

[The Natural Philosopher]

You dont listen or think, do you?


--
"What do you think about Gay Marriage?"
"I don't."
"Don't what?"
"Think about Gay Marriage."

[Andrew Gabriel]

In article <niucc5$41u$3...@news.albasani.net>,

The Natural Philosopher <t...@invalid.invalid> writes:
> On 03/06/16 20:56, Andrew Gabriel wrote:
>> In article <niorkr$df7$1...@news.albasani.net>,
>> The Natural Philosopher <t...@invalid.invalid> writes:
>>> On 02/06/16 08:52, Andy Burns wrote:
>>>> MM wrote:
>>>>
>>>>> See http://www.littletyke.myzen.co.uk/crimped_ferrules.jpg
>>>>> What is the correct name for them
>>>>
>>>> uninsulated bootlace ferrules
>>>>
>>>>> and where do I find them?
>>>>
>>>> rs, cpc, farnell, rapid etc
>>>>
>>>>> I've always tinned the wire strands to (a) make it easier to fit them
>>>>> into the screwed holder and (b) stop the strands from splaying when
>>>>> tightening the screw.
>>>>
>>>> Not a good idea as the solder is soft and creeps under the pressure of
>>>> the screw terminal, loosening over time.
>>>>
>>> Then you didn't tighten it enough to start with.
>>>
>>> Think of the solder as a mastic to fill the gaps between the copper, but
>>> the copper makes the joint
>>
>> It's never permitted to do this because the solder creeps over time
>> under pressure and contact pressure is lost, causing the connection
>> to then overheat.
>
> You dont listen or think, do you?

I corrected your misinformation, particularly as
it is well known to be dangerous.
I see lots of people have done that too.

[MM]

No. Not in 50 years.

>>>I have been doing just that for nearly 50 years and never had any
>>>issues. Maybe I know how to properly tin a cable and how to properly
>>>tighten a screw and Tomlinson doesn't. ;-(
>>
>>I served 7 years as an apprentice motor fitter so I know a bit about
>>over-tightening screws or nuts.
>
>And, (if not under tightening or using a torque wrench) there is a
>definite 'feel' to this sort of thing that is easy to assume with
>others.

Novices don't have that 'feel'. You learn the hard way by stripping a
few threads first.

>>You get a feel for how tight is tight after 60 years.
>
>Indeed. ;-)
>
>A couple of times I've assisted people (over the phone) doing what I
>would consider very basic tasks (like torquing down a cylinder head or
>replacing an alternator) that have ended in tears (for them, not me)
>because they don't have 'the feel'. The two instances I am thinking
>of, one incorrectly read the torque wrench and the engine stud snapped
>before the wrench clicked (when those with the feel might have
>suspected something wasn't right) and similar with the guy changing
>the alternator, stripping the thread on the tension bracket.
>
>In fact, I've nearly stopped asking / allowing people to help me do
>stuff because of how often something get's lost or broken (of mine)
>whilst they are doing so, or just not doing it to my standards.
>
>I was with BT 5 years and when I left my apprenticeship - soldering
>test piece was still in the display cabinet as no one else had managed
>100/100 whilst I was there. I found it quite easy whilst others
>obviously struggled ... like I would if I was plastering a wall or
>trying to program to fix something on Linux (or any other OS of
>course). Everyone to their own etc. ;-)
>
>Cheers, T i m

MM

[The Natural Philosopher]

No, you simply went along with misguided thinking that was wrong, and
dangerous, and didn't listen to or even try and understand the arguments
as to why it was misguided.


--
"Anyone who believes that the laws of physics are mere social
conventions is invited to try transgressing those conventions from the
windows of my apartment. (I live on the twenty-first floor.) "

Alan Sokal

[Dave Plowman (News)]

In article <niue0b$j47$1...@dont-email.me>,

Andrew Gabriel <and...@cucumber.demon.co.uk> wrote:
> >> It's never permitted to do this because the solder creeps over time
> >> under pressure and contact pressure is lost, causing the connection
> >> to then overheat.
> >
> > You dont listen or think, do you?

> I corrected your misinformation, particularly as
> it is well known to be dangerous.
> I see lots of people have done that too.

I'd ask those who tin the ends of the leads what current they are taking
from the circuit?

It's often thin wires which would be easier to fit if tinned. So if only a
couple of amps at peak, less likely to give trouble regardless.

What would happen at the maximum continuous rating - ie 13 amps - would be
interesting. Even some factory fit moulded plugs will get warm or even hot
at full load.

--
*I don't work here. I'm a consultant

[T i m]

On Sat, 04 Jun 2016 12:40:57 +0100, MM <kyli...@yahoo.co.uk> wrote:

<snip>

>>
>>It seems to work eh. Can you *ever* remember having a problem after
>>wiring something using that process?
>
>No. Not in 50 years.

Quite, so we are obviously doing something right or 'different' to
those who seem to have issues.

>
>>>>I have been doing just that for nearly 50 years and never had any
>>>>issues. Maybe I know how to properly tin a cable and how to properly
>>>>tighten a screw and Tomlinson doesn't. ;-(
>>>
>>>I served 7 years as an apprentice motor fitter so I know a bit about
>>>over-tightening screws or nuts.
>>
>>And, (if not under tightening or using a torque wrench) there is a
>>definite 'feel' to this sort of thing that is easy to assume with
>>others.
>
>Novices don't have that 'feel'. You learn the hard way by stripping a
>few threads first.

Good point and something I'd not thought of doing till you said that
when teaching someone how tight to do up something [1]. Easy to get
some sacrificial nuts and bolts in the vise and let them see just how
little torque you sometimes need to strip / shear something.

Cheers, T i m

[1] As a support rather than design 'engineer', most of my efforts
would be based around how to do, rather than not do something. eg, It
would be 'how to tighten cylinder head bolts in sequence and stages',
rather than to purposefully do it wrong and damage something. This is
generally because I'm generally helping someone repair something they
want or need, or allowing them to learn on my stuff, rather than just
showing them *how* to do it as such.

[T i m]

On Sat, 4 Jun 2016 11:11:09 +0100, Mike Tomlinson <mi...@jasper.org.uk>
wrote:

Except, I never suggested any 13A plug had such a thing, just that I
would like the option as I think they are a good idea.

But, trust Tomlinson not to be even able to get the story straight
(and couldn't if he tried, he's not wired that way). I'm not surprised
he can't though, one of the pitfalls of being a killfiling coward is
you can't guarantee to get the whole / correct story. Not that things
like the truth or (real-world) facts ever stopped him for making up
his own story of course. ;-(

Hey, and if a 13A plug terminal did have a tongue, even he might be
able to wire one up properly!!!

Cheers, T i m

[dennis@home]

On 04/06/2016 17:08, T i m wrote:
> On Sat, 04 Jun 2016 12:40:57 +0100, MM <kyli...@yahoo.co.uk> wrote:
>
> <snip>
>>>
>>> It seems to work eh. Can you *ever* remember having a problem after
>>> wiring something using that process?
>>
>> No. Not in 50 years.
>
> Quite, so we are obviously doing something right or 'different' to
> those who seem to have issues.

The problem is that as an individual you are unlikely to notice any
problems, even if you do ten a day for 50 years the failure rate is low
enough that you wouldn't notice. However when you have millions of
joints you will notice the problem. Conversely if there are millions of
people doing it then some of them will have problems.

[T i m]

On Sat, 4 Jun 2016 17:30:46 +0100, dennis@home
<den...@nowhere.invalid> wrote:

>On 04/06/2016 17:08, T i m wrote:
>> On Sat, 04 Jun 2016 12:40:57 +0100, MM <kyli...@yahoo.co.uk> wrote:
>>
>> <snip>
>>>>
>>>> It seems to work eh. Can you *ever* remember having a problem after
>>>> wiring something using that process?
>>>
>>> No. Not in 50 years.
>>
>> Quite, so we are obviously doing something right or 'different' to
>> those who seem to have issues.
>
>The problem is that as an individual you are unlikely to notice any
>problems, even if you do ten a day for 50 years the failure rate is low
>enough that you wouldn't notice.

Ok.

> However when you have millions of
>joints you will notice the problem.

But there is a good chance that those that have problems *because*
they weren't *correctly* tinned over those joints made without
tinning could be tending towards nill.

>Conversely if there are millions of
>people doing it then some of them will have problems.

Yes, especially the incompetent ones (like Tomlinson, as he has shown
us himself in this very thread!). ;-)

Cheers, T i m

[dennis@home]

On 04/06/2016 18:09, T i m wrote:
> On Sat, 4 Jun 2016 17:30:46 +0100, dennis@home
> <den...@nowhere.invalid> wrote:
>
>> On 04/06/2016 17:08, T i m wrote:
>>> On Sat, 04 Jun 2016 12:40:57 +0100, MM <kyli...@yahoo.co.uk> wrote:
>>>
>>> <snip>
>>>>>
>>>>> It seems to work eh. Can you *ever* remember having a problem after
>>>>> wiring something using that process?
>>>>
>>>> No. Not in 50 years.
>>>
>>> Quite, so we are obviously doing something right or 'different' to
>>> those who seem to have issues.
>>
>> The problem is that as an individual you are unlikely to notice any
>> problems, even if you do ten a day for 50 years the failure rate is low
>> enough that you wouldn't notice.
>
> Ok.
>
>> However when you have millions of
>> joints you will notice the problem.
>
> But there is a good chance that those that have problems *because*
> they weren't *correctly* tinned over those joints made without
> tinning could be tending towards nill.

They could but industry says they aren't.

[T i m]

On Sat, 04 Jun 2016 13:41:49 +0100, "Dave Plowman (News)"
<da...@davenoise.co.uk> wrote:

>In article <niue0b$j47$1...@dont-email.me>,
> Andrew Gabriel <and...@cucumber.demon.co.uk> wrote:
>> >> It's never permitted to do this because the solder creeps over time
>> >> under pressure and contact pressure is lost, causing the connection
>> >> to then overheat.
>> >
>> > You dont listen or think, do you?
>
>> I corrected your misinformation, particularly as
>> it is well known to be dangerous.
>> I see lots of people have done that too.
>
>I'd ask those who tin the ends of the leads what current they are taking
>from the circuit?
>
>It's often thin wires which would be easier to fit if tinned. So if only a
>couple of amps at peak, less likely to give trouble regardless.

I'd agree that it would be more typical that *I* would generally tin
(and fold and tin) finer wires, simply to hold them together and have
a better chance for the screw to have something to bite down on than I
might on heaver / less stranded wire.

>
>What would happen at the maximum continuous rating - ie 13 amps - would be
>interesting.

I think if properly tinned (eg, not 'over ' soldered) and tightened
correctly / sufficiently then nothing.

>Even some factory fit moulded plugs will get warm or even hot
>at full load.

They can indeed and here is one I saw earlier. ;-

https://dl.dropboxusercontent.com/u/5772409/13A%20plug.jpg

Mate had his compressor plugged into a rubber trailing socket that was
previously wired directly into the previous (higher power) compressor.

The fuse had gone a couple of times recently so because it was
connected to it's own MCB someone though a solution would be some
silver foil round the fuse. ;-(

I think a combination of a poor quality moulded plug (in comparison
with an MK one) and plugged into a rubber trailing socket (even a
branded one) allowed localised heating and potentially further stress
on the fuse.

To help them isolate the fault, I checked it wasn't seized, that the
caps were ok and after replacing the plug, that the motor ran ok on
it's own. I then connected it back up and let it run up to full
pressure and the plug was still cold (probably helped by being plugged
into a decent Metalclad socket).

I've suggested they get the plug replaced with a decent (MK) one and a
decent Metalclad socket fitted to the wall beside the compressor.

Cheers, T i m

[T i m]

On Sat, 4 Jun 2016 18:37:12 +0100, dennis@home

What industry regularly tins the sort of joints we are talking about
then, for you to get this data?

No one is saying (especially me) that tinning stranded wires is
recommended, potentially outside harsh / marine environments in an
effort to prevent corrosion to the exposed wires.

However, what I am saying is I have no experience of any stranded
wires I have tinned and used in mains plug type applications have ever
been an issue.

I am (fully) aware of the issues tinning a stranded cable (in an
effort to make it more manageable, to resist corrosion or make it
offer more material for some screw terminals to grip) like stiffening
of the (previously more flexible) 'flex' and it therefore requiring
more support than it might otherwise.

Point. If you take a bundle of stranded cable and 'tin' them (not over
solder them), and trap them in a receptacle and clamp them in place,
even if the solder is more malleable than the copper, where does the
copper go? The copper may move within the solder *until* it's all
touching each other strand, just as it would if there had been no
solder there in the first place.

It's quite possible that a tinned wire may resist strands moving and
therefore maintain a *better* overall tension / connection than an
untinned one?

Cheers, T i m

[dennis@home]

That is exactly the point it does as you say.
The problem is it doesn't do it instantly as you tighten the screw.
It happens over the following month/years as the solder creeps out of
the joint.
The result is the joint becomes looser and the resistance goes up.
This increases the heating and things go down hill from there.

>
> It's quite possible that a tinned wire may resist strands moving and
> therefore maintain a *better* overall tension / connection than an
> untinned one?

Not a chance with normal solder.

[T i m]

On Sat, 4 Jun 2016 19:53:30 +0100, dennis@home
<den...@nowhere.invalid> wrote:

<snip>

>> Point. If you take a bundle of stranded cable and 'tin' them (not over
>> solder them), and trap them in a receptacle and clamp them in place,
>> even if the solder is more malleable than the copper, where does the
>> copper go? The copper may move within the solder *until* it's all
>> touching each other strand, just as it would if there had been no
>> solder there in the first place.
>
>That is exactly the point it does as you say.

Good, then there shouldn't be a problem. ;-)

>The problem is it doesn't do it instantly as you tighten the screw.

Then I suggest you aren't tightening the screw correctly
sufficiently.

>It happens over the following month/years as the solder creeps out of
>the joint.

The solder has no where to go as the copper wires are already pressed
up against each other as tight as they can.

>The result is the joint becomes looser and the resistance goes up.

It can't because there is nowhere for the copper wires to go and
what's more, the gaps between them are filled with solder, unlike a
non-tinned cable.

>This increases the heating and things go down hill from there.

Yes, if would, if your theory was correct.

>
>>
>> It's quite possible that a tinned wire may resist strands moving and
>> therefore maintain a *better* overall tension / connection than an
>> untinned one?
>
>Not a chance with normal solder.

Please explain how (as TNP suggested), tinning a group of cable
strands can make the copper less stable than it was originally.

Ok, take a bundle of sticks, pull them tightly together and then wrap
some putty round them. Put a Jubilee clip over the putty and do it up
till the clip forces out all the surplus putty and pulls the sticks
tightly together. How is that going to be any less tight than a bundle
clamped up without the putty (if tightened up sufficiently /
properly)? How is it going to be as tight (a bundle) as one supported
by the putty in the gaps that the sticks could otherwise move into
(had it not been for the putty)?

Cheers, T i m

[MM]

On Sat, 04 Jun 2016 17:08:53 +0100, T i m <ne...@spaced.me.uk> wrote:

>On Sat, 04 Jun 2016 12:40:57 +0100, MM <kyli...@yahoo.co.uk> wrote:
>>Novices don't have that 'feel'. You learn the hard way by stripping a
>>few threads first.
>
>Good point and something I'd not thought of doing till you said that
>when teaching someone how tight to do up something [1]. Easy to get
>some sacrificial nuts and bolts in the vise and let them see just how
>little torque you sometimes need to strip / shear something.

That's nothing! I well remember a class at Maidstone Technical
College, where we apprentices attended one day and two evenings a
week, when we were introduced to the wondrous torque wrench (cue witty
remarks). One lad still managed to strip a thread. The lecturer asked,
did you not adjust the torque wrench correctly? Yes, he murmured, but
I didn't think that was tight enough. Dunno whether he passed his City
& Guilds later...

When I worked in the prototype department at Ford-Werke in Cologne,
building the first Granadas, Cortinas, Escorts and Capris in
protototype form long before production started, we had to use a
torque wrench for practically everything. AND we had to paint a little
stripe down the side of the bolt/nut with bright yellow paint so that
the engineers/designers could see whether one had moved during 100
laps around the test track in Lommel. (Cologne-Merkenich had its own
small test track as well.)

>
>Cheers, T i m
>
>[1] As a support rather than design 'engineer', most of my efforts
>would be based around how to do, rather than not do something. eg, It
>would be 'how to tighten cylinder head bolts in sequence and stages',
>rather than to purposefully do it wrong and damage something. This is
>generally because I'm generally helping someone repair something they
>want or need, or allowing them to learn on my stuff, rather than just
>showing them *how* to do it as such.

How many times have I watched novices tighten bolts or nuts holding a
flange and observed how they frequently tighten ONE nut up tight, then
the NEXT nut up tight, and so on. When I point out that the correct
way is to pinch down the flange as evenly as possible, tightening each
nut/bolt a little at a time, they think I'm nit-picking. There are
probably hundreds of thousands of owner-"maintained" motor vehicles on
the roads with dodgy practices like this built in, as if the original
designers didn't know better than Bert next door.

MM

[MM]

On Sat, 4 Jun 2016 17:30:46 +0100, dennis@home
<den...@nowhere.invalid> wrote:

I really don't think any one person could ever achieve "millions of
joints" in a lifetime. Aren't you getting a little bit carried away?

MM

[MM]

On Sat, 4 Jun 2016 18:37:12 +0100, dennis@home

Ha, industry once used "inflammable" as "not flammable"!

MM

[Capitol]

> eby the putty in the gaps that the sticks could otherwise move into

> (had it not been for the putty)?
>
> Cheers, T i m
>

The reason for not tinning is that it is cheaper in production.
Either tinned, untinned, sleeved or crimped joints can give problems in
mass production. Particularly with crimped joints, you are at the mercy
of the crimp material hardness and the behaviour of the copper wire
being crimped, which will have a variety of ductile behaviour. The auto
industry suffers badly from poor crimp quality, particularly when it is
done in third world countries. Mercedes went through a very bad period
some 10 years ago on their ML product line. Military crimped connections
are always IME tested for strength before being mounted in the
equipment. Consumer products are pot luck!

[Capitol]

Dave Plowman (News) wrote:
> In article<niue0b$j47$1...@dont-email.me>,
> Andrew Gabriel<and...@cucumber.demon.co.uk> wrote:
>
>>>> It's never permitted to do this because the solder creeps over time
>>>> under pressure and contact pressure is lost, causing the connection
>>>> to then overheat.
>>>>
>>> You dont listen or think, do you?
>>>
>
>> I corrected your misinformation, particularly as
>> it is well known to be dangerous.
>> I see lots of people have done that too.
>>
> I'd ask those who tin the ends of the leads what current they are taking
> from the circuit?
>
> It's often thin wires which would be easier to fit if tinned. So if only a
> couple of amps at peak, less likely to give trouble regardless.
>
> What would happen at the maximum continuous rating - ie 13 amps - would be
> interesting. Even some factory fit moulded plugs will get warm or even hot
> at full load.
>
>

Yes very few 13A plugs can handle 13A continuously. A good
manufacturer checks the performance, but even then they are at the mercy
of the contact resistance in the socket.

[T i m]

On Sun, 05 Jun 2016 07:56:10 +0100, MM <kyli...@yahoo.co.uk> wrote:

>On Sat, 04 Jun 2016 17:08:53 +0100, T i m <ne...@spaced.me.uk> wrote:
>
>>On Sat, 04 Jun 2016 12:40:57 +0100, MM <kyli...@yahoo.co.uk> wrote:
>>>Novices don't have that 'feel'. You learn the hard way by stripping a
>>>few threads first.
>>
>>Good point and something I'd not thought of doing till you said that
>>when teaching someone how tight to do up something [1]. Easy to get
>>some sacrificial nuts and bolts in the vise and let them see just how
>>little torque you sometimes need to strip / shear something.
>
>That's nothing! I well remember a class at Maidstone Technical
>College, where we apprentices attended one day and two evenings a
>week, when we were introduced to the wondrous torque wrench (cue witty
>remarks). One lad still managed to strip a thread. The lecturer asked,
>did you not adjust the torque wrench correctly? Yes, he murmured, but
>I didn't think that was tight enough.

Beautiful. ;-)

> Dunno whether he passed his City
>& Guilds later...

Well, we can all make mistakes and if it was a lesson learned ...

>
>When I worked in the prototype department at Ford-Werke in Cologne,
>building the first Granadas, Cortinas, Escorts and Capris in
>protototype form long before production started,

(That must have been interesting?)

>we had to use a
>torque wrench for practically everything.

And in theory, so you (we) should.

> AND we had to paint a little
>stripe down the side of the bolt/nut with bright yellow paint so that
>the engineers/designers could see whether one had moved during 100
>laps around the test track in Lommel. (Cologne-Merkenich had its own
>small test track as well.)

Sounds like fun.

>>
>>[1] As a support rather than design 'engineer', most of my efforts
>>would be based around how to do, rather than not do something. eg, It
>>would be 'how to tighten cylinder head bolts in sequence and stages',
>>rather than to purposefully do it wrong and damage something. This is
>>generally because I'm generally helping someone repair something they
>>want or need, or allowing them to learn on my stuff, rather than just
>>showing them *how* to do it as such.
>
>How many times have I watched novices tighten bolts or nuts holding a
>flange and observed how they frequently tighten ONE nut up tight, then
>the NEXT nut up tight, and so on.

;-(

> When I point out that the correct
>way is to pinch down the flange as evenly as possible, tightening each
>nut/bolt a little at a time, they think I'm nit-picking.

I think it's because they don't think and / or realise that something
that looks 'solid' is often very flexible, even something as
substantial as a cylinder head or pipe flange.

> There are
>probably hundreds of thousands of owner-"maintained" motor vehicles on
>the roads with dodgy practices like this built in, as if the original
>designers didn't know better than Bert next door.

Yup. There is quite a science in fastness and I'd hate to think (as
you say) how many things (typically vehicles) are going around with
them incorrectly set? A classic example of where uneducated people
sometimes get to play with such things are wheel nuts (both the
drivers and the tyre fitters).

I think it all comes under the saying 'You can manage what you can
measure' and whilst I'm sure an experienced engineer can get a
fastener torque pretty close by 'feel', especially on those fasteners
that are not 'critical', the only way you can truly know what torque
are applying is to use the tight tool for the job. Even with that
there is room for error, like if the figures are given with the
fastener used dry and the fitter uses an anti-seize grease or thread
locker, without making suitable compensation.

Cheers, T i m

[The Natural Philosopher]

On 05/06/16 09:54, Capitol wrote:

>
> The reason for not tinning is that it is cheaper in production.

And these days with lead free solder mandated, its not a great way to do
anything.

> Either tinned, untinned, sleeved or crimped joints can give problems in
> mass production. Particularly with crimped joints, you are at the mercy
> of the crimp material hardness and the behaviour of the copper wire
> being crimped, which will have a variety of ductile behaviour. The auto
> industry suffers badly from poor crimp quality, particularly when it is
> done in third world countries. Mercedes went through a very bad period
> some 10 years ago on their ML product line. Military crimped connections
> are always IME tested for strength before being mounted in the
> equipment. Consumer products are pot luck!

Every way to terminate a flexible wire to a solid post or whatever has
problems. Crimps and IDC connections are prone to water ingress and
corrosion, solder joints to stress concentrations and resultant metal
fatigue.

There is no 'best' way. Just the balancing of a lot of factors and te
whole solution needs to consist in all case not just of the joint
itself, but the means by which its shortcomings are addressed. E.g. gel
filled crimps, or sleeved and supported solder joints.


--
The theory of Communism may be summed up in one sentence: Abolish all
private property.

Karl Marx

[T i m]

On Sun, 05 Jun 2016 09:54:31 +0100, Capitol <sp...@whereva.uk> wrote:

<snip>

> The reason for not tinning is that it is cheaper in production.

And I have seen cable end tinning used in a (Datacomms / mobile radio)
production environment myself (for several years) with workers on a
flow-line tinning the ends of a stranded cable in a 'Tinning pot' pre
the cable being screwed into a terminal connector. These were
typically transformer winding 'ends' and where a cable form would join
a PCB (where the PCB or connected item may need to be easily replaced
in the future).

>Either tinned, untinned, sleeved or crimped joints can give problems in
>mass production.

Of course.

> Particularly with crimped joints, you are at the mercy
>of the crimp material hardness and the behaviour of the copper wire
>being crimped, which will have a variety of ductile behaviour.

And how many strands didn't make it into the crimp etc.

> The auto
>industry suffers badly from poor crimp quality, particularly when it is
>done in third world countries.

I will often make a joint in 3 stages. First crimp (where possible)
to provide the 'mechanical connection. Then I'll solder to support the
crimp (electrically and mechanically and to minimise corrosion) and
then heat shrink to further help support the cable / connector
interface and 'seal' the insulation to the connector.

>Mercedes went through a very bad period
>some 10 years ago on their ML product line. Military crimped connections
>are always IME tested for strength before being mounted in the
>equipment.

Ok.

>Consumer products are pot luck!

Quite. ;-)

Cheers, T i m

[PeterC]

On Sun, 05 Jun 2016 10:04:25 +0100, T i m wrote:

>>How many times have I watched novices tighten bolts or nuts holding a
>>flange and observed how they frequently tighten ONE nut up tight, then
>>the NEXT nut up tight, and so on.
>
> ;-(
>
>> When I point out that the correct
>>way is to pinch down the flange as evenly as possible, tightening each
>>nut/bolt a little at a time, they think I'm nit-picking.
>
> I think it's because they don't think and / or realise that something
> that looks 'solid' is often very flexible, even something as
> substantial as a cylinder head or pipe flange.

I was taught (i.e. told) to do this when I was about 15. Well worth while
for something like a BSA C10 head with, IIRC, 8 bolts.
The opposite - if that's the right word - is also true: slacken off a bit at
a time. This has the same advantage of not allowing distortion with the
added benefit of not undoing n-1 fasters and finding that the last one
(isn't it always?) is stuck. Because there's been, say, 1 flat on each, if
one is stuck it's simple to redo the others and possibly still use the
device.
Another thing worth doing - found out the hard way many years ago - is
always back-turn self-tappers in plastic or any screw in wood when replacing
them. Often the screw is so aggressive that a random start will remove
what's left of the thread.
--
Peter.
The gods will stay away
whilst religions hold sway

[T i m]

On Sun, 5 Jun 2016 10:58:33 +0100, PeterC
<giraffe...@homecall.co.uk> wrote:

>On Sun, 05 Jun 2016 10:04:25 +0100, T i m wrote:
>
>>>How many times have I watched novices tighten bolts or nuts holding a
>>>flange and observed how they frequently tighten ONE nut up tight, then
>>>the NEXT nut up tight, and so on.
>>
>> ;-(
>>
>>> When I point out that the correct
>>>way is to pinch down the flange as evenly as possible, tightening each
>>>nut/bolt a little at a time, they think I'm nit-picking.
>>
>> I think it's because they don't think and / or realise that something
>> that looks 'solid' is often very flexible, even something as
>> substantial as a cylinder head or pipe flange.
>
>I was taught (i.e. told) to do this when I was about 15.

I learned to do so from the Haynes Workshop manual for the Fiat 850
(engine) I rebuilt when I was 15. ;-)

> Well worth while
>for something like a BSA C10 head with, IIRC, 8 bolts.

I'd say it's probably not a bad idea on anything retained by 'a few'
bolts. I just feel more comfortable first just nipping up all the nuts
in a criss-cross order and then fully tightening them similarly. Even
with 4 wheel nuts. ;-)

>The opposite - if that's the right word - is also true: slacken off a bit at
>a time. This has the same advantage of not allowing distortion with the
>added benefit of not undoing n-1 fasters and finding that the last one
>(isn't it always?) is stuck.

Hehe, yes, it's that often the case.

>Because there's been, say, 1 flat on each, if
>one is stuck it's simple to redo the others and possibly still use the
>device.

Yup, good tip. And the same applies to things that have to be removed
in sequence. There is no point undoing something that *will* require a
new gasket if you can't get it clear, or do whatever needs doing next
if you can't also remove another component.

>Another thing worth doing - found out the hard way many years ago - is
>always back-turn self-tappers in plastic or any screw in wood when replacing
>them. Often the screw is so aggressive that a random start will remove
>what's left of the thread.

Yup, in fact I did that yesterday (4 self tappers retaining a plastic
cover over the start / run caps on a compressor) but I think someone
had been there before. I allowed them to find the previous threads but
2 of the 4 I could feel weren't going to nip up but were tight enough
to fall out. The clue that might be the case was the plastic still
trapped on two of the screw heads. ;-(

Now, if it were mine or I wasn't in a rush I would have checked to see
if the holes were blind and / or if it was safe to take them deeper
and then find some longer or possibly slightly thicker screws and
replace all 4.

The other thing you see is people over tightening things like
waterproof covers with rubber gaskets underneath where you want to try
to minimise the distortion to ensure the seal remains consistent.
Instead you see the 4 corners pulled down hard and great big gaps at
the middle of the long edges. ;-(

I wonder if 'mechanical feel / empathy' is something you can actually
learn?

Oh, the other thing is destroying something useable to fix something
else when the straight solution is available and not expensive. It's a
bit like say stripping one classic car to restore another ... when
it's possible that someone else along the line will want to rebuild
the donor. ;-(

Don't get me wrong, I can see the financial and practical merits (I've
done it myself) but I don't really like doing so (unless the thing you
are taking the parts from is never going to be useable again, like
taking the engine out of an otherwise unsalvageable body shell). [1]

Cheers, T i m

[1] We built our kitcar mainly out of one Mk2 Escort Saloon that had
been 'lightly' <g> rolled and therefore unlikely to ever be repaired.
That said, now you see what price a rusted out Mk2 shell is going for
... ;-(

[Mike Tomlinson]

En el artículo <145c9ncyxe24r.1sqpku4r3mzni$.d...@40tude.net>, PeterC
<giraffe...@homecall.co.uk> escribió:

>Another thing worth doing - found out the hard way many years ago - is
>always back-turn self-tappers in plastic or any screw in wood when replacing
>them.

Agreed. Not just self-tappers, but any screw or bolt. Turn
anticlockwise slowly until you feel/hear the click, then start turning
from there.

--
(\_/)
(='.'=) systemd: the Linux version of Windows 10
(")_(")

[T i m]

On Sun, 5 Jun 2016 12:15:56 +0100, Mike Tomlinson <mi...@jasper.org.uk>
wrote:

>En el artículo <145c9ncyxe24r.1sqpku4r3mzni$.d...@40tude.net>, PeterC
><giraffe...@homecall.co.uk> escribió:
>
>>Another thing worth doing - found out the hard way many years ago - is
>>always back-turn self-tappers in plastic or any screw in wood when replacing
>>them.
>
>Agreed. Not just self-tappers, but any screw or bolt. Turn
>anticlockwise slowly until you feel/hear the click, then start turning
>from there.

Sounds like something someone not familiar with doing up nuts and
bolts might do, if done routinely?

I think I might have done it under extreme circumstances (a
particularly big or bizarre / plastic thread) but certainly not with
the regularity I do with re-fitting self-tappers into (worst case)
plastic or thin / soft materials.

Cheers, T i m

[dennis@home]

Try doing the same thing by pushing a screw into the bundle of sticks
and note what happens, report back and let us know.

[T i m]

On Sun, 5 Jun 2016 16:16:49 +0100, dennis@home
<den...@nowhere.invalid> wrote:

<snip>

>> Please explain how (as TNP suggested), tinning a group of cable
>> strands can make the copper less stable than it was originally.
>>
>> Ok, take a bundle of sticks, pull them tightly together and then wrap
>> some putty round them. Put a Jubilee clip over the putty and do it up
>> till the clip forces out all the surplus putty and pulls the sticks
>> tightly together. How is that going to be any less tight than a bundle
>> clamped up without the putty (if tightened up sufficiently /
>> properly)? How is it going to be as tight (a bundle) as one supported
>> by the putty in the gaps that the sticks could otherwise move into
>> (had it not been for the putty)?
>
>
>Try doing the same thing by pushing a screw into the bundle of sticks
>and note what happens, report back and let us know.

Don't need to mate as 50 years of doing what I have and seeing it done
the same way on a production line is all I need.

However, for your (miss)point to be valid you would have stand on the
the sticks, not 'push a screw into them' to make anything like a valid
comparison.

The point is, anything tightly bundled (so all parts already in
contact) aren't going to be free to move as far when held together
(eg, with solder) than they would when left 'free', even when that
binding agent isn't as hard as the material itself.

Trap that 'bound bundle' in a confined space and clamp sufficiently
and the outcome can only be 'better' than doing so without the extra
binding.

It's *only* when the individual strands aren't in close proximity
before being tinned and / or the clamping force not sufficient do you
get any problems, over an above what would have been there already.

Anyway, I'll carry on doing what I've done (as it works), as and when
I feel it is appropriate thanks. ;-)

Cheers, T i m

[Tim+]

T i m <ne...@spaced.me.uk> wrote:

Seriously, when did you last wire a plug when the wire completely filled
the hole in the pin? Unless the wire completely fills the hole your jubilee
clip analogy is wrong.

As long as the wire is smaller than the hole the strands will spread when
compressed. Solder stops immediate spreading but does nothing to stop
delayed spreading.

Tim

--
Trolls and troll feeders go in my killfile

[The Natural Philosopher]

On 05/06/16 21:50, Tim+ wrote:

>
> As long as the wire is smaller than the hole the strands will spread when
> compressed. Solder stops immediate spreading but does nothing to stop
> delayed spreading.
>

That's right. Solder is used because it doesn't stick wires together or
to anything else. Stands to reason.

I mean circuit boards have components that gradually work their way out
of the board and walk away . Eny Fule Kno That.


> Tim
>


--
"In our post-modern world, climate science is not powerful because it is
true: it is true because it is powerful."

Lucas Bergkamp

[T i m]

On Sun, 5 Jun 2016 20:50:08 -0000 (UTC), Tim+ <tim.d...@gmail.com>
wrote:

Yesterday (well nearly and after I'd doubled it over <g>). The thing
is it doesn't have to fill the hole, it just has to not be allowed
back past the screw itself. eg, The available 'void' for the strands
shrinks as you do up the screw. However, with fine stranded wire and
some cheap screw terminals, it is possible for loose strands to get
lost up the sides of the screw and therefore lower the current
carrying capacity of the cable at that point. Also more chance of
cutting through the strands that do get trapped (because there are now
less of them).

> Unless the wire completely fills the hole your jubilee
>clip analogy is wrong.

Well, not really. The point is that the strands are twisted pre
tinning, helping to (mechanically) bind them together. Think of the
whipping on the end of a rope.

>
>As long as the wire is smaller than the hole the strands will spread when
>compressed.

See above.

>Solder stops immediate spreading but does nothing to stop
>delayed spreading.

See above, unless your understanding of how it works can affect how
I've had it working for ~50 years? ;-)

When I get rid of some dead equipment I generally cut the mains lead
off and if the plug is moulded on, leave it like that but if it's a
re-wireable plug, I remove the wire manually, making it ready to
re-use next time. I have a clear storage box full of such leads,
plugs, trailing sockets etc.

So, when I remove a plug that I have previously fitted (I can tell
from the layout of the wiring, the accuracy of the insulation trim
back and the tinning of the conductors (where suitable)), I make a
mental note, just how tight the screws still are. I'll leave you to
guess what I have found so far. I would certainly notice a burnt wire!

FWIW I designed, built and ran a mobile disco for about 7 years and
*every* plug on all the kit was fitted by me, many of which (because
of the low current concerned) used thinner cables and so I tinned the
conductors. In spite of them being handled nearly once a week and
bounced about in the van, not once did I have an issue (with screw
terminals or any connector wiring for that matter).

Now, YMMV but I can only tell you how I experience it. ;-)

Cheers, T i m

p.s. If I'm doing anything 'detailed' with anyone who know me, they
will generally give it to me to do because they know I'll do a neater
job than them. That could partly be because of my dexterity compared
with them, my experience with the tools and that I probably pay
greater attention to the details than them and will *always* start
again if I'm not happy it's the best it can be. 'Thattle do' isn't
really in my vocabulary, especially re things like that. Whilst it
generally works out for the best, it does take more time (for me).

[MM]

On Sun, 05 Jun 2016 10:04:25 +0100, T i m <ne...@spaced.me.uk> wrote:

>On Sun, 05 Jun 2016 07:56:10 +0100, MM <kyli...@yahoo.co.uk> wrote:
>
>>On Sat, 04 Jun 2016 17:08:53 +0100, T i m <ne...@spaced.me.uk> wrote:
>>
>>>On Sat, 04 Jun 2016 12:40:57 +0100, MM <kyli...@yahoo.co.uk> wrote:
>>>>Novices don't have that 'feel'. You learn the hard way by stripping a
>>>>few threads first.
>>>
>>>Good point and something I'd not thought of doing till you said that
>>>when teaching someone how tight to do up something [1]. Easy to get
>>>some sacrificial nuts and bolts in the vise and let them see just how
>>>little torque you sometimes need to strip / shear something.
>>
>>That's nothing! I well remember a class at Maidstone Technical
>>College, where we apprentices attended one day and two evenings a
>>week, when we were introduced to the wondrous torque wrench (cue witty
>>remarks). One lad still managed to strip a thread. The lecturer asked,
>>did you not adjust the torque wrench correctly? Yes, he murmured, but
>>I didn't think that was tight enough.
>
>Beautiful. ;-)
>
>> Dunno whether he passed his City
>>& Guilds later...
>
>Well, we can all make mistakes and if it was a lesson learned ...
>
>>
>>When I worked in the prototype department at Ford-Werke in Cologne,
>>building the first Granadas, Cortinas, Escorts and Capris in
>>protototype form long before production started,
>
>(That must have been interesting?)

It was a tremendous experience, which I had never anticipated. I
finished my apprenticeship at a small garage near Maidstone and
wondered what to do next. Someone said, they're looking to hire guest
workers in Germany. So I wrote to Ford-Werke (in German, using what
little of the language I knew at the time), they invited me to Cologne
and paid for my petrol and provided free accommodation in a Ford
hostel. I did the interview, and two weeks later they offered me a
job. The Prototypenbau was about as far removed from the little garage
in terms of working practices as it was possible to get. It was almost
as clean as a laboratory for a start. Safety was paramount. Before
moving under a vehicle on a hoist a foreman had to check that it was
safe etc etc. Even the tiniest drop of oil spilled on the floor had to
be wiped away immediately. I got paid very well indeed compared to
Maidstone. Later I had studied enough spoken and written German to
move on to the salaried staff as a technical translator, never got my
hands dirty again -- except when wiring plugs -- and was paid a lot
more!

MM

[MM]

On Sun, 05 Jun 2016 11:48:02 +0100, T i m <ne...@spaced.me.uk> wrote:

>[1] We built our kitcar mainly out of one Mk2 Escort Saloon that had
>been 'lightly' <g> rolled and therefore unlikely to ever be repaired.
>That said, now you see what price a rusted out Mk2 shell is going for
>... ;-(

If I had my time over again I would restore classic cars for a living.
Have you SEEN the price of these nowadays if in concours condition?!!
I had several old cars, some pre-war, even before I was legally old
enough to drive. Look at what you have to fork out now, even for a
pre-war Austin Seven.

MM

[PeterC]

On Sun, 05 Jun 2016 11:48:02 +0100, T i m wrote:

> The other thing you see is people over tightening things like
> waterproof covers with rubber gaskets underneath where you want to try
> to minimise the distortion to ensure the seal remains consistent.
> Instead you see the 4 corners pulled down hard and great big gaps at
> the middle of the long edges. ;-(
>

Yes, malleable (in the sense of rubber etc.) gaskets are rather 'delicate'
in this way.
I also found out that using any form of grease on a gasket can cause
leakage, or at least more so than with just a dry gasket. Possibly the
grease is compressed in voids and stops the gasket being fully deformed. The
exception might be a /very/ thin coating (wipe on - wipe off) of silicone
grease in plumbing.

> I wonder if 'mechanical feel / empathy' is something you can actually
> learn?

I seem to have it 'naturally', but that's more likely to come from p'ing
about with stuff from a very early age.
I once removed and replaced the head from an old car, open-ended spanners,
torqued up from memory of undoing.
Got it to work, checked with a torque wrench, all moved a minute amount
ecept for one that went one flat - failure!

[PeterC]

On Sun, 5 Jun 2016 12:15:56 +0100, Mike Tomlinson wrote:

> En el artículo <145c9ncyxe24r.1sqpku4r3mzni$.d...@40tude.net>, PeterC
> <giraffe...@homecall.co.uk> escribió:
>
>>Another thing worth doing - found out the hard way many years ago - is
>>always back-turn self-tappers in plastic or any screw in wood when replacing
>>them.
>
> Agreed. Not just self-tappers, but any screw or bolt. Turn
> anticlockwise slowly until you feel/hear the click, then start turning
> from there.

Not usually necessary with metal, but the spring-loaded top of a 376 carb.,
under the tank, definitely?
I used some Turbo Ultra wood screws. Removed one and a load of wood came out
with it - that was turned to engage!

[T i m]

On Mon, 06 Jun 2016 08:09:31 +0100, MM <kyli...@yahoo.co.uk> wrote:

>On Sun, 05 Jun 2016 11:48:02 +0100, T i m <ne...@spaced.me.uk> wrote:
>
>>[1] We built our kitcar mainly out of one Mk2 Escort Saloon that had
>>been 'lightly' <g> rolled and therefore unlikely to ever be repaired.
>>That said, now you see what price a rusted out Mk2 shell is going for
>>... ;-(
>
>If I had my time over again I would restore classic cars for a living.

Hmm, I guess given the right facilities it could be ok. I say that
because I have already done my share of repairing rusted monocoque and
can't say I really enjoy it.

>Have you SEEN the price of these nowadays if in concours condition?!!

Yup.

>I had several old cars, some pre-war, even before I was legally old
>enough to drive. Look at what you have to fork out now, even for a
>pre-war Austin Seven.

Yup, a feeling made worse with the knowledge I cut up and gave to the
scrap man a reasonable (by today's standards, worth nothing at the
time) Mk1 Escort 2 door shell when building the kitcar and sold my 2
Morris Minor vans and Mums 4 door saloon for next to nothing.

Maybe people in the know are just fed up with all this 'automatic'
stuff you get on cars these days and want to take back some control
and actually driving the things themselves again. ;-)

I really do think we are being isolated and insulated from the outside
world more and more and modern cars are a classic example of that.
It's as if people want to be sitting in their lounge but able to go
from A to B? It may be something one might appreciate when you get
older, don't actually enjoy mechanics / driving or have to regularly
drive long distances.

On that though, I think my Mrs is a better bike rider than car driver
(and she's admitted the same) and I think that's because when on a
motorbike you are very much aware of your surroundings and have to
focus more on the actual process than you do in a car, making you more
involved (the reverse of modern 'automatic everything' cars).

Cheers, T i m

[Mike Tomlinson]

En el artículo <1mmyokjffe78$.rq5mu1kxkml2$.d...@40tude.net>, PeterC
<giraffe...@homecall.co.uk> escribió:

>Not usually necessary with metal

I find it helps prevent cross-threading, especially if the bolt or nut
is a bit reluctant and you're not sure if it's just stiff due to crap on
the threads (e.g. on a car) or the beginning of a crossed thread.

It also works for spark plugs - something you really don't want to cross
the threads on.

[T i m]

On Mon, 6 Jun 2016 08:39:38 +0100, PeterC
<giraffe...@homecall.co.uk> wrote:

<snip>

>I also found out that using any form of grease on a gasket can cause
>leakage, or at least more so than with just a dry gasket. Possibly the
>grease is compressed in voids and stops the gasket being fully deformed.

Could be. Again, I am often obsessive with the cleanliness of such
mating surfaces and will remove location dowels and put the item on
some fine wet and dry on a sheet of plate glass to remove an high
spots and burrs. If I can do that to both surfaces all the better and
I don't think I've ever had anything treated like that leak
afterwards. It goes from that to using (red) Hermetite (and new
gasket) when the surfaces are less than ideal.

> The
>exception might be a /very/ thin coating (wipe on - wipe off) of silicone
>grease in plumbing.

I know some people use the silicone 'Instant Gasket' and I have once
or twice but I find it too messy for general use. I have sheets of
gasket paper and would rather make my own than use Instant gasket
because I prefer the idea of something 'stable' in the joint.

>
>> I wonder if 'mechanical feel / empathy' is something you can actually
>> learn?
>
>I seem to have it 'naturally', but that's more likely to come from p'ing
>about with stuff from a very early age.

Same with me then possibly. That said, both my Dad and his Dad were
d-i-y craftsmen (carpenters) and many people of my age (and
background) also had to get involved in stuff, simply because there
wasn't an affordable alternative? My Dad had company cars so he never
got involved in their upkeep (outside the routine checks) but as I
generally 'found' my vehicles (people offered them to be broken /
cheap) I gained an interest in getting them going as well (along with
electrical items etc) for my own use.

>I once removed and replaced the head from an old car, open-ended spanners,
>torqued up from memory of undoing.
>Got it to work, checked with a torque wrench, all moved a minute amount
>ecept for one that went one flat - failure!

Hehe. I think that would count as a big pass! (considering). ;-)

Cheers, T i m

[T i m]

On Mon, 6 Jun 2016 08:42:00 +0100, PeterC
<giraffe...@homecall.co.uk> wrote:

>On Sun, 5 Jun 2016 12:15:56 +0100, Mike Tomlinson wrote:
>
>> En el artículo <145c9ncyxe24r.1sqpku4r3mzni$.d...@40tude.net>, PeterC
>> <giraffe...@homecall.co.uk> escribió:
>>
>>>Another thing worth doing - found out the hard way many years ago - is
>>>always back-turn self-tappers in plastic or any screw in wood when replacing
>>>them.
>>
>> Agreed. Not just self-tappers, but any screw or bolt. Turn
>> anticlockwise slowly until you feel/hear the click, then start turning
>> from there.
>
>Not usually necessary with metal, but the spring-loaded top of a 376 carb.,
>under the tank, definitely?

I did it earlier with the plastic top off the coffee jar but rarely on
any std nuts and bolts. But then I rarely have to think which way to
turn a nut or bolt, no matter what way up it or I am. The Mrs often
asks me which way to turn on a garden tap or stopcock. My answer is
'the same way you normally undo a tap' but that doesn't seem to help.
;-(

>I used some Turbo Ultra wood screws. Removed one and a load of wood came out
>with it - that was turned to engage!

They can be quite aggressive can't they.

Cheers, T i m