BLF Interest list for Very High Current Beryllium Copper springs Pt1(ENDED)

BlueSwordM I’m happy to pay for both the big and small springs now before you order if that’s easier for you.

Same here BSM, I’m with skinny_tie; whatever you want…. Payment in Full, partial payment, down payment, whatever you want…. you call it. :slight_smile:

When’s the last date to change our orders?

Not yet.

We are at 1741 big springs and 1257 small springs.

The big spring group buy will end once we get at about 1950 springs.

That is the same thing with the small spring: it will end at 1950 springs.

Please add 6 small and 6 big to my order.

I’d like to add 10 more big springs and 10 more small springs to my order. Thanks!

Please add 20 more small springs to my order. Thanks.

List has been updated.

Ok, one last thing before the springs are being made, as the BeCu 1mm wire has been ordered and shipped.

We initially, or rather I initially, chose zinc as plating as that would be the best compromise between cost, mechanical properties, and electrical conductivity.

However, I have thought about using nickel tin for plating instead. Because tin has a lower melting point, it would be easier to solder a bypass to than zinc, if you actually need to haha, and since it is a bit softer than zinc, it would provide about better contact area with the battery, and provide about the same electrical conductivity. And nickel substrate below the tin.

So, which one would you prefer?

A zinc plating, or a nickel-tin plating?

/\ … As far as I am concerned BSM, whatever you think best. :+1: . :slight_smile:

I just want to make sure I’m making the best spring for our purposes.

I understand. Maybe djozz or someone else who is really knowledgeable about this will weigh in with some factual info.

Thanks teacher.

I do know quite a bit about springs know, but I would like to know of people maybe more knowledgeable than me.

Sure thing BSM. But let me be clear, that was not meant to imply you did not know. I apologize if it came across that way. :slight_smile:

I say just go with which ever you feel is best. Unless you feel there is someone who knows more about it than you do… go with what you think best. :slight_smile:

I have always had good luck with nickle plating in electrical situations so far but either should work.

Definitely not Zinc.

Zinc is very difficult to solder, and the joint will be weak.

I suggest you get some information about the solderability of the nickel-tin plating before committing.

Gold plating would be superior. Hence the ubiquity of it for torch springs.

I think ENIG (electroless nickel immersion gold) plating would be the best, and is a standard PCB manufacturing process, though maybe unfamiliar for a spring manufacturer.

One of the reasons high quality PCBs are made with ENIG on the pads, to maintain consistent solderability in storage. Or cheap ones are “HASLed” (hot air solder levelled) during manufacture, whilst the copper is still clean. HASL has a shelf life, depending on environmental conditions, it can become pretty much unusable after a short while.

Clean copper has good solderability with standard fluxes. Beryllium copper however is much less easy to solder even with activated fluxes. Specialist organic fluxes are needed for best results. So some sort of surface plating is necessary. Again, I’d suggest gold, if data is not forthcoming for the nickel-tin proposed.

These springs have to be soldered to tail PCB or driver. An easy, reliable, not brittle, solder joint using standard solder and standard flux is paramount if they are going to be good.


Page 2.

If going for gold, it must not be too thick (as if :money_mouth_face:, because it too can embrittle solder joints if over-done.

I may be over-thinking this, with my MIL-aerospace hat on, but zinc is a no-no.

The problem with gold plating is that it costs significantly more in small quantities.

It would actually cost double for a gold coating since it is a small order.

It would go from to 350$ to 700$+

Also, I did know about ENIG.

Finally, nickel-tin is actually a great coating material for soldering.

Nickel is first off deposited onto the substrate, then a layer of tin is deposited on it. This allows for good contact on non-even surfaces, and good solder ability, even better than gold in most cases, while also having a shiny silver finish.

TLDR: Gold is too expensive for small batches, so nickel-tin is the way to go for our battery springs.

If nickel-tin coating doesn’t increase the price go for it.

OK, gold is out. Nickel-tin it is.

But nickel-tin is not necessarily as you describe, it’s can also be done in a co-deposition electrolytic process resulting in a uniform nickel-tin alloy.

I’ve never used it, so have no experience to offer.

Do check that the nickel-tin that you are offered has the good solderability, that is important.

Good luck.