Warning - Stackpole resistors eat your side cutter

[thunter0512]

WARNING - Stackpole Electronics CF and CFM resistors (and possibly others) have steel leads which damage your side cutters.

Recently I have been using lots of these resistors while building replacement boards for my Lab-8/e not realising that they have copper plated steel leads which are then tinned.
I found out when mysteriously my second quality German made side cutter (made by Knipex) developed "nicks" in the cutting edge.

I had these two side cutters for about 40 years and never cut anything but component leads with them.
They have been in pristine condition until recently.

While ordering more components from Digikey I stumbled across the Stackpole datasheet for their CF and CFM resistors and discovered that they use steel leads.
If you use a magnet these resistors stick to it.
Now it is clear why my two side cutters developed those annoying "nicks".
These side cutters were never meant to be used to cut steel wire.

I now bought two new Knipex side cutters and will test component leads with magnets before ruining the cutters again (these cutters are expensive but very good quality).

Check through hole component datasheets and avoid those with steel leads if you value your side cutters.
I also wonder what copper plated steel leads means for corrosion of the assembled board if there is any exposure to humidity.

Please don't use cheap Chinese resistors.

Best regards
Tom Hunter

 

[Chuck(G)]

That's not uncommon--I have TO-5 transistors with steel leads--and they were made by GE in the USA. The advantage of steel is that it's stronger and less likely to fail under fatigue. Copper-plated, it solders just as easily as pure copper.

I purchase my inexpensive flush cutters by the box of 10 with the idea that they'll eventually become unusable.

There are side cutters with tungsten carbide blades. Schmitz of Germany makes some very fine (and expensive) ones. Here's another cheaper one. Opticians and dentists routinely have to cut stainless steel wire.

 

[Roland Huisman]

Hi Tom,

Steel is not uncommon in electronic parts... Look at my Chinese LED's...
I have had this also with resistors of various brands. Transistors the same story.



But also old 74xx chips can have plated steel pins...



I lost count about how many side cutters I've wasted in the past years. The last years I'm using Erem cutters. These seem to be quite strong. But for some reason I always tend to wear out these things faster then the most people do :sigh: But when I have some rough work to do, I get an old cutter to do the job. But like you say, it is always good to realise what kind of material you are cutting.

Regards, Roland

 

[Chuck(G)]

Got a friend who's an orthopedic surgeon? They use cutters that are made for steel wire--and quite often, they're discarded after a single procedure.