Springs!!

All I know about springs is in the OP, but your plan makes sense.

I’m not sure what your conclusion is from “they can only handle 6/7 A” ? It just is a way to explain that the resistance is lower than pure copper, I guess that it is the same as the phosforbronze spring that you are planning.

Are you going to sell the springs and are prepared for the hassle that comes with it?

Why are you interested in machinability?

@hlKARlnoob Cost. 45% IACS Beryllium Copper, or even just pure copper, is very hard to machine. And therefore, is at a big premium. This is what he told me anyway, and I do believe him on the research I have done.

The engineers at the Chinese companies said to me the same thing: 38% IACS beryllium copper is just a a tiny bit more expensive than phosphor, but 45% IACS is much more expensive to machine, in exchange to being more mechanically weak in terms of springiness.

This is why BeCu 45%IACS springs are so expensive on IntlOutdoor compared to bronze springs on Kaidomain, even for a smaller spring. It is just because it is more expensive to machine.

@djozz, I am planning to make a group buy, yes. Not all of the springs made are for the group buy of course. I’m going to keep some of them to replace all of the springs in my lights, so about 20 pcs if I only make 200 pcs of them. Then I am keeping about the same amount for prototyping a product that I am currently engineering, so about 20 pcs.

The rest 150pcs I am probably going to sell in a GB at cost depending on the price they quote me, just so the BLF members can try them out, and see how really good they are.

Before that of course, I am going to do a similar test to yours in 2014, just a bit update :laughing:

I have done group buys locally before, but not on a global scale like BLF. So it is going to be a trial on how good I am on the topic.

TLDR: Going to keep about 50 springs for myself and a project, then going to sell them in a group buy if they are good enough. Otherwise, it is going to be part of my hobby money spent on 200 springs.

I don’t get it. You don’t machine to produce springs; springs use a forming process to obtain their shape. At least, that’s what I thought.

Ok sorry, misltranlation on my part. I have asked him again, and he said that while 45% IACS beryllium copper is stiffer than copper after being worked on, it is actually slightly softer than copper before being worked on.

From what I can translate from French, he said that when forming 45% IACS beryllium copper into a spring, it has a slightly higher chance of breaking than copper, and much higher chance than 38% IACS beryllium copper. That is because 38% IACS beryllium copper contains more impurities added when making it, such as nickel and cobalt, giving it higher mechanical strength.

Finally, containing a higher percentage of copper and beryllium just makes it more expensive to produce.

TLDR: 38% IACS beryllium copper, while a bit weaker electrically, is stiffer than 45% IACS, before and after being formed, and is much less expensive to manufacture into a spring.

Sorry for the mistranslation, but I don’t speak or write much about these kind of topics much, like science, so I don’t always know the appropriate terms.

You don’t machine springs, they are bent into shape.
And also you DO want compressibility, if it’s too stiff it will plastically deform when compressed which is not what you want for a spring, it should remain in elastic deformation.

This makes sense. And no problem about the mistranslation, this is how we learn. :+1: :beer:

[video:]Beavis And Butthead - Boing! - YouTube

@Enderman, yes, you want compressible enough springs, not too stiff. Beryllium copper 38% IACS is good in that regard. In fact, phosphor bronze and beryllium copper 38% IACS are quite good in this regard.

However, as seen by djozz in his test, springs that collapse are a problem when looking for higher conductivity, as they collapse quite easily. This is not in relation to stiffness, but elastic memory when being compressed.

We want spring with good elastic memory.

Stiffness Elastic memory goes in an increasing manner:

Copper < Beryllium Copper 45% IACS < Phosphor Bronze B-2 15% < IACS-Beryllium Copper 38% IACS ≤ Phosphor Bronze B-2 19% IACS < Stainless steel

Edit: Haha I absolutely love Beavis and Butthead. Such a great show :+1:

Edit 2: IMPORTANT

I made a mistranslation again. By stiff

Beryllium copper IACS 38% is a good material for a spring in terms of stiffness, and is the best balance between electrical conductivity, cost, and elastic memory. Phosphor bronze is a bit cheaper, but we already these in most sizes. A tall, not short high current spring is what’s lacking.

Well, besides a nice laugh I've had after discovering the title of hIKARInoob's linked video (to my Spanish native speaking mind that sounds :-D “moñoñoñoñoñoño”), I have an interesting question in this regards fellows: What is the relative hardness of these spring alloys versus the hardness of the usual standard carbon steel cutting pliers are usually made of? You know, if the allow is slightly softer it can be of cutting edge :-D help.

Cheers ^:)

It would be interesting to make it narrow for reverse mounts. By reverse I mean that the thick end touches battery. Lone Oceans does so to gain more space on his drivers.

Well, guys, we may have a problem.

Most of the Chinese companies got back to me, and they said that while they said Beryllium Copper 38% IACS is not much more expensive than phosphor bronze, they would have to order separetely the material, and for 200 pcs, it would probably exceed my original price point.

The only way I could get them at a reasonable price would be at onne of thr companies which sells 1000 pcs of them for 350$ everything included, since it is a custom order

Now, that would be a bit overkill. Even a group buy would be hard pressed to sell all of these units, and I do not have enough hobby money to afford all of that, and space.

So, unless someone, or many people, are willing to split the difference, I don’t think the group buy is going to be successful.

So it is a bit problematic.

Just as well. Beryllium is a nasty metal, I’ve had to use it in aerospace applications (mostly the oxide beryllia BeO for it’s thermal properties, with tight control throughout the lifecycle), but it is not something to be used ubiquitously.

It used to be used in solid rocket motors, but that was insane.

“Formation of BeO from beryllium and oxygen releases the highest energy per mass of reactants for any chemical reaction, close to 24 MJ/kg”

I doubt there is any danger in spring wire, but other alternatives are available with decent design.

https://www.osha.gov/SLTC/beryllium/index.html

I know Beryllium from the aerospace application as well, due to stupid high specific E-modulus. Odd this is not mentioned in the osha link.

The problem is the quantity.

Do you think I should make an group buy interest page for the Beryllium Copper Springs in the same size as the Djozz springs? They can handle twice the current, so they could be a replacement for spring bypasses.

If I can have enough interest in enough springs(at least 500 springs to be sold) then I will consider making the order.

My springs had a base diameter of 10mm, that was just a bit too wide for a standard tailboard, I would suggest a 9mm base diameter.

I’d buy a few :slight_smile:

You are lucky. Here are the measurements I gave to the Chinese companies:

- Material: C17530(Berrylium Copper) with IACS of 38%

- Spring upper diameter: 7mm

- Spring base diameter: 9mm

- Spring thickness: 1mm

- Spring height: 12mm

- Plating: Zinc plating/gold plating

- Total number of coils: 5

- Free length: 0 mm

UPDATE

I am going to make an interest list soon enough.

Maybe some retailers like MTN would be interested in getting large quantities?

I’ve also used it in F1 brake calipers. Superb, but so expensive, as for the the protection we had to use machining them … :open_mouth:

Now banned in F1, got to keep it real.

Ideal for springs though, nothing better.

Maybe you can talk to Richard at Mountain to see if he wants to buy a portion of it for his store.