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.
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”
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 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.
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.
Moi? Wrong? Never! :party: The only way silver plating will have any significant effect on electrical conductivity will be at microwave frequencies where the electrons are carried at the surface of the material (aka skin effect). For DC/audio freqs, the bulk material is where the conductivity occurs.
Well, then I have to wonder why a major spring manufacturing company would say “But one material, beryllium copper, has the distinction of being one of the best for battery contacts.” And go on and on about it’s robust ability to take compression and maintain shape far more than other materials while offering greater strength and thinner profiles. It would stand to reason that if the company makes springs, nothing but springs, they would have a pretty good grasp on the best materials to make them from.
Wikipedia even says that BeCu has better thermal and conductive properties than aluminum, performing only slightly less than pure copper itself.
At any rate, they’re far better than gold plated steel springs. Can one deduct that a thin gold plating carries as little conductive properties as the aforementioned rat’s derriere? After all, there’s so little there…
Just wondering, what is “too little material to affect things”? One mouse turd in a gallon of tea is very little, but I suppose you wouldn’t drink the tea?