I would be in for about 30 but not until after the first of the year. I would also get more if we can get longer ones for switches.
Sweet, thanks for the info.
I’m in for $15 worth of springs excluding shipping if we get over 600 units price cut.
I could use 10. Any chance they could be made thicker?
20-30 for me 
+2
The only problem with longer/thicker springs for tailcaps is that it’s in addition to the driver springs. So, with these being special order due to their material it would be another starting place. 100-200 on the initial step at more than $1.50 ea. That’s another $150-300.
If we can get enough people wanting that larger tail spring I reckon we can do it both ways, but they’re going to be quite expensive as there’s not much chance we’ll get 1000 together in a group buy. Remember, longer and thicker will be exponentially more expensive than these. And at some point if the spring rate doesn’t match top and bottom then the stronger spring is not going to be compressed much if any while the weaker spring will take all the slack.
Recently, I’ve been making 5/16” diameter brass rod connections on the driver and allowing the tail spring to take up all the slack itself. This is because I’ve been stacking chips on the outside of the driver, so I used the solid rod to avoid a compressed spring shorting out the whole thing.
Do you have a pic of the type of spring we are talking about? Current capacity? How compressible are they? I could use a few if the specs are right
Alex, I’m waiting for those specifics. Being a custom spring, the info I posted is all I have at the moment. When they get back to me with specifics on the silver plated beryllium I’ll add it to the original post and make a notation in the thread title.
This is just talking out my butt since I don’t have much knowledge in this area
But if we got longer tail springs with a good taper couldn’t we flip it upside down and clip excess length of to use on the drivers
Just my thought if it’s total nonsense then please ignore this
Page 257 of the catalog PDF;
Silver Plated Beryllium Copper
For a C cell 0.81mm Diameter wire, O.D. of coil base is 0.54 inches, inner diameter is 0.33 inches and a free length of 0.52 inches and is a “Stock” item but I think the code is “Special Order”
If the springs are plated with silver, don’t they tarnish quite quickly?
Tarnish? I was wondering how they’ll look after the lithium fire. How does one extinguish a lithium fire, boron or graphite- halon?
Please measure the contact pad in your driver. What is the maximum diameter spring it can take without jeapordizing contact with legs on chips under compression for the larger diameter body. Think about how many amps you wish to flow through this spring. Now think about how big a vent incident or explosion you are willing to deal with. It’s not ALL fun and games.
I’m in for 20-40 springs, depending on others’ interest. If there ain’t enough demand, than I’ll get 40.
Mattaus, can I presume you’re selling these springs along side your FET switches?
I had figured on putting the spring upside down, so I checked how big of a diameter I had on the negative pole of my batteries, poop! About .38 inches on average and the contact pad is only .36 inches in diameter. So then I figured that the AA size stock beryllium spring would work and Ta-Da WRONG! The base is .39 inches for the stock beryllium spring. So much for my creative input.
Depending on price, id be in for min 20.
A spring that tapers from 4mm to 8mm seems ideal. That way it could be mounted inverted if the driver pad is on the smaller side and it still wouldn't splay larger than a positive battery pole.
I'd take 25 of each, driver side and tailcap switch side (if we end up doing those). Even more if the tailcap switch side compresses flat.
20 should do for me.
Don’t know how many… depends on the details.
Depending upon the alloy, BeCu has an electrical conductivity of 7-50% that of pure copper…