Stranded flex with a mind of it's own

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Inspired by a current topic about flex, just recently I have noticed several light fittings be supplied with flex that is very awkward to work with.

You just cannot twist the strands together to solid it up a bit. It just instantly undoes itself, so making a neat connection is virtually impossible.

The best I can do with it is bend it over and shove it in the terminal quick.

Anyone else experienced this rubbish?
 
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You click "report" and make a request, which will be seen by the mods.
How the hell do I edit the title?
 
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this is the stuff in fine, hair-like whiskers?

assuming you haven't got a soldering iron handy, I wonder if a bootlace crimp would help? Some appliances come with them, for testing in the factory.
 
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Not sure what it's construction is, but yes, very fine whiskers.

Got a feeling we are going to be seeing a lot of it soon.
 
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Multi-stranded wire is used for leads that will be frequently flexed is use such as telephone handset cables ( the old corded telephones ) test meter leads and cables mobile things such lift cabins. Test leads of 0.25 sq mm have 50 strands. Some lift cables that take power to the lift cabin can have over 500 strands per conductor.
 
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Multi-stranded wire is used for leads that will be frequently flexed is use such as telephone handset cables ( the old corded telephones ) test meter leads and cables mobile things such lift cabins. Test leads of 0.25 sq mm have 50 strands. Some lift cables that take power to the lift cabin can have over 500 strands per conductor.
You remind me of "Litz wire" - have you ever tried to solder (or do anything almost else!) with it? :)

Kind Regards, John
 
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Hi,

Was it anything like this?
20211030_192337.jpg

It was a cable pendant kit from Next.
https://www.next.co.uk/style/st201114/413279#413279

A really horrible thing to wire, but the worst part was neatly cutting the weave.

I think the cable reminds me of high temperature soldering iron leads.
...and it isn't magnetic, also it's a lot stiffer than test lead wire! :)
 
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Litz wire, so often used in coils for wireless equipment, ( in the days when wireless used coils in tuning circuits ).

A similar wire was tinsel wire ( mainly in telephone equipment ) which had threads laid in with the copper tinsel strands.

Terminations were made by tightly wrapping tinned copper wire around the tinsel and then bending this back and binding it in place with colour coding silk thread to form an eyelet.

tinsel wrapped eyelet.jpg


Image from Telephony Part 1 ( Herbert and Proctor, 1946 )
 
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Litz wire, so often used in coils for wireless equipment, ( in the days when wireless used coils in tuning circuits ).
I know (only too well!), but that didn't make my experiences of trying to deal with it any the happier :)

I'd be surprised if I don't have some specimens thereof in some dusty corner of my cellar!

Kind Regards, John
 
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assuming you haven't got a soldering iron handy, I wonder if a bootlace crimp would help?
Definitely bootlace ferrule, though might need to be slightly bodged with an over-sized one crimped right down if the wire is so bad it won't go into a correctly sized ferrule. I always try and use ferrules on stranded cable.
Soldering isn't an acceptable method for dealing with the problem. The soft solder creeps readily at room temperature and will remove contact pressure in screwed terminals.

And yes, I remember when I first came across tinsel cord and wondered "what strange stuff is this, and how on earth do I solder it ?" (or words with that general meaning :whistle:)
 
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Terminations were made by tightly wrapping tinned copper wire around the tinsel and then bending this back and binding it in place with colour coding silk thread to form an eyelet.

I have made a few of those up in the distant past. It's the only way to deal with that stuff. I think the last time was back in the 80's for some instrumentation leads on a bit of machinery, where the copper leads kept fracturing due to the extreme movement and vibration. I came up with the bright idea of using curly telephone wire, but found it was tinsel wire and impossible to terminate in the usual way, so I ended up binding the ends with 5amp fuse wire.
 
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From my collection of phones through the ages used as stage props:

20211102_074121.jpg

Edited for spelling. Have I discovered a new sub-atomic particle, the "collecton", or is it already known? ☺
 
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