Beryllium copper

[Craig Sawyers]

Hi all

Fixing my HP34C calculator, and I need a small amount of beryllium copper strip to make replacement battery contacts (the originals are usually broken off - like on mine!).

I need something around 0.25mm thick (10 thou).

Does anyone have a small piece lurking?

Cheers

Craig

[CambridgeWorks]

I have a roll somewhere approx 1 or 2M long x 50mm wide I am pretty certain is that material. Not 100% certain though. Will dig it out this weekend if it is where I THINK it is, measure thickness and send a picture.
However, if anyone else can help in the meantime, please feel free to offer.
Rob

[G.Castle]

Hi Craig.

I have some, (un plated), spring copper pm your address and I'll pop a bit in an envelope.

Greg.

[CambridgeWorks]

Well, In my garage, to get a bottle of wine, I just found one pack of a similar strip, but NOT the one I was looking for. THIS one is "Johnson Matthey Sil-fos brazing alloy 155 Ag:Cu:P 644-700C melting range". Comprises 2 strips (50mm wide approx) that are enclosed in polythene sleeve, coiled and held together with a black tywrap. I don't think it is springy enough for your purpose Craig.

The ones i AM looking for are 2 or 3 strips, similar sized coil and held together with a clear tywrap. These may be in my outside workshop? Will check this weekend.
I remember scrounging them from my scrap man friend Ron, (who was a true friend) and he mentioning the word Beryllium, which at he time I recognised from rf power transistors in my youth. Oxide was not mentioned by Ron I hasten to add!
If/when I find it, it just might reveal how good my description from memory actually is.
Will keep in touch.
Rob

[cliff2903]

I think Sil-fos was more commonly known as tri-foil and was used when silver soldering carbide tips on to steel shanks to stop tips cracking due to different cooling/shrinkage rates

[CambridgeWorks]

Found it, but seems to be just copper strip as no springiness at all, it just bends and doesn't return to original shape. It is 20 thou thick. The silfos is fairly springy, to a point and is 5 thou thick.
Rob

[emeritus]

I have some very springy coppery strip, probably beryllium copper or phosphor bronze, salvaged from a skip at Marconi's several decades ago. It might not be thick enough: 8.4 thou by 35mm wide and 5.0 thou by 1" wide. It has definite grain and cracks when attempting to bend at 90° sharp in one direction, as I found out some years ago when I last used it to make replacement brushes for the 3V motor of my godson's favourite toy electric car. You're welcome to a few inches of each, realistically I am never going to need it all.