Magnetic leadouts.

[Nanozeugma]

Anyone else noticed that several new stock modern capacitors and resistors appear to have magnetic leadouts?
These are from English suppliers but may, of course, be of Chinese manufacture.
So far as I am aware, traditional components used tinned copper leadouts.
Although the modern ones take solder well enough, there must be ferrous metal in there to attract a magnet.
I wonder whether they are using tinned steel to save money?

[G8HQP Dave]

Yes, this has been going on for some years. I have noticed that some component leads feel quite different when being bent by hand: more resistant than copper at first, but then they bend more easily. I suspect this means they will suffer fatigue fractures much more quickly if repeatedly re-bent.

[G6Tanuki]

Originally Posted by Nanozeugma

Anyone else noticed that several new stock modern capacitors and resistors appear to have magnetic leadouts?
These are from English suppliers but may, of course, be of Chinese manufacture.
So far as I am aware, traditional components used tinned copper leadouts.
Although the modern ones take solder well enough, there must be ferrous metal in there to attract a magnet.
I wonder whether they are using tinned steel to save money?

Have seen this for a couple of decades at least: I have some old ISKRA resistors (made in what was then called Yugoslavia) like this.

I suspect it's more to do with being able to 'set' the legs accurately when using PCB-stuffing robots than anything to do with cost.

Some diodes have one magnetic and one non magnetic lead, I noticed this 40 odd years ago.

[Bazz4CQJ]

I recently had a lead on a new component snap when I tried to put a sharp 90' bend in it. Never seen that before.

B

[Andrew B]

Ever tried soldering what you thought was copper wire and found out it was really aluminium?

[60 oldjohn]

Yes these trimmers, I had a batch where one leg only was aluminium the other copper, this particular one both legs are ferrous. Luckily I have some aluminium solder, Tandy brand, old but still works.


Ever tried to solder USB lead? don't know what it was but Aluminium, stainless steel, and ordinary 60/40 solder would not work on this particular one. I eventually cut the plug end open to investigate and it had been crimped.


John.

[Refugee]

Has anyone tried soldering the wire from stripped down un-fused C13 cables.
The fine conductors are springy.

[TonyDuell]

I think I found some similar wire in cheap (poundshop) telephone extension cables. Very springy and did not want to take solder at all.

[Refugee]

Phone cables were always difficult to solder.

[TonyDuell]

Originally Posted by Refugee

Phone cables were always difficult to solder.

Well, 'Tinsel wire' is (cotton core with thin copper strands wound round it, used when you need flexibilty). Old telephone handset cables and even line cords were often that.

But the telephone extension leads I mentioned looked like normal multi-strand copper wire. Just very springy and hard to solder.

[Ian - G4JQT]

Also some single-core plastic coated wire is magnetic. Tried to get simple electric motor going as a kids' demo. Worked with thick enamelled copper wire, but similar wire with plastic coat just kept jumping and sticking to the magnet!

Have we got a reason yet for this magnetism? Is it for engineering or cost reasons? Presumably its cause is ferrous and not nickel.

Ian

[Dave Moll]

I would imagine it's a matter of cost in that copper is more expensive.

The Royal Mint made a similar decision many years ago - to make "copper" coins out of mild steel with just a plating of copper.

[trsomian]

Some semiconductors have used steel leads for years, TO5, TO18, TO72 to name a few. I used to get involved with repairing boards that lived out on a narrow gauge railway line, where the cause of the problem was frequently that a transistor wire had rusted away

[G6Tanuki]

Some of the original Ediswan "top-hat" transistors from the late-1950s [XA101 etc] had plated-steel leadouts too.

And they rusted.