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

Some questions:

The springs will be “gold plated” in other words gold color?

In a build what do you think its better to use big spring in driver or in tailcap?
Using the big and the small in a flashlight will be too tight?

Thanks

Use the small spring on drivers that have components on the back of them. A Simple FET+1 driver doesnt have any components on the back so you can use a big spring. A driver with a half dozen 7135 modules on both sides will require this skinny spring so it wont interfere with those components

1. Gold plated= gold color and gold plating for corrosion resistance

We will be using a zinc plating as it has a bit lower cost, and still good corrosion characteristics and a nice silver look, which I prefer over a gold plating.

2. Big springs almost always used in the tailcap, and small springs are used on the driver, as the contact pad of the drivers are usually way too small for such a large spring at the base(9mm), and not interference with small components.

3. No it will not be too tight. This is why dual beryllium copper springs are the grail of flashlights. It allows for universal cell compatibility, and shock absorption, compared to a single spring and a brass button, which upon a large enough shock, it will transfer the kinetic energy to the cell, and may collapse the terminal. This is no problem for a dual spring light. Most springs can’t provide low enough resistance for high power lights, but using beryllium copper 38% IACS mitigates this.

Good info BlueSwordM. … Thanks again for doing this!!! :beer:

Thank you again teacher.

I would like to add that I also searched for brass springs, but they would probably collapse instantly if a tube were over tightened.

Zinc plating? Really? How much will that change the overall electrical resistance of the spring?

:+1: … :slight_smile:

@DavidEF

Nothing that is even measurable at all. It’s just a coating, between 0,75um and 1,25um, or 0,00075mm-00125mm.

The coating is so thin it does not affect electrical characteristics at all.

Nickel could be used, but zinc does actually protect the metal more from corrosion more than nickel, is less expensive, and actually has 5% more conductivity than nickel(27% vs 22%).

TLDR: For springs, zinc and gold are probably the best bet, but zinc spring is cheaper and still great, so we are going with this,

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After going through many similar projects I would feel much better seeing the final product tested by a BLF member before we go plunging into a group buy.
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If that is information your willing to share I would also be interested. I have considered having batches made in XYZ sizes many times. If Richard is just special I understand though, he holds a pretty warm place in my heart too :slight_smile:
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Gold would be my first choice… Did they give a price? I can live with zinc. As long as we are absolutely sure to get something besides bare copper……
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If there is a price break like that at 2000pc I would also be very interested to know. And +1 for the mechanical properties.
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Finally, thank you so much for doing this BlueSwordM!!! Put me down for 100 + 100. If there is a significant price drop at 2000pc as mentioned above I’d be in for a lot more.

+1. Thanks again for the effort. :+1:

1. The supplier is not very keen on providing samples with less than a 1000 springs. I will take the plunge for the purchase, but that means I will not be able to start the real group buy in 3 weeks to amass the necessary hobby funds to fund this project, if the demand grows to say 2000 springs.

However, if I can get a sample of something like 10 springs, that problem could easily be solved as that would prove they are good suppliers and good springs.

2. Yes, ASF, I will contact you too so you can sell springs at your store too, once the group buy is over. Spring bypasses are great, but they require so much work and time, so very high current springs are a blessing.

3. Yes they did give a price. And the gold coating is about 5% more expensive. And I also prefer a silver look compared to gold for some reason :laughing:

4. 2000pcs should be even less expensive per spring. It will be amazing if I can reach a price of 0,25$US per spring, or even lower.

Finally, you are very welcome. I am very honored for you to be thankful to me, vesture of blood. And, added 100 small springs and 100 big springs. I think I’ll have to halt the group buy interest list soon enough though at a total of 2000pcs, including the big and small springs.

A pre-made sample of the same material even if not the exact dimensions costs them nothing. Just to be able to check the fit and finish and material. I don’t think anyone would hold it against you if you wanted to assume less risk and press them on this issue, I certainly would.

The only problem would be that since beryllium copper is not usually used for battery springs, there is a minimum order quantity going on.

I already have a spring with about the same dimensions, but only in phosphor bronze. That is the Kaidomain phosphor bronze spring in the picture.

Other than the material and 2.2x the electrical conductivity, there should be no difference between the two.

Nevertheless, I will ask again.

I really hope it goes well.

In for 30 of the smaller springs also.

May do more of both if we hit 2000(?) and see a price break.

If we do hit 2000pcs total, and I receive a sample from my supplier, yes, we will go above that amount, and see a price break.

BlueSwordM it looks to me like making 2000 large and 1000 small would be pretty easy to do, especially if there’s a bigger price break at 2000.
Might help if you contact them and find out the difference. I know for myself if they are cheaper each piece I’m going to up my order a little more. The main thing being if they are really good, everyone’s gonna want them. You really need to test samples even if there something they have surplus from another order. Just my two cents :wink:
Thanks for doing the GB. :+1:

I have already contacted them. It just takes time for them to respond.

And I will probably make 2000 big springs and 2000 small springs so they get even cheaper each

And when I get a sample, then the group buy is going to commence.

Also, thanks for the encouragement.

put me down for 10 big 10 small

The list has been updated again.

I hate to say it again, but I am absolutely impressed by the feedback of the community.

Also, what kind of name would you like for this spring?

I have thought about the BLF ULPS, being the BLF Ultimate High Power Spring.

Is that good name? What do you suggest?

Finally, I will test the conductivity of the spring when I get it, and how well it holds up under stress.

Name??? Why would you name a spring? :laughing: