I still have not got the pm with payment details, in meantime some of you got your springs. Should I be worried?
He might have overlooked you. I just paid a couple days ago.
Same here, I haven´t received any PM as well.
Me too. Didn’t receive PM.
From 10/6/18
Don’t worry. I’ve started PMing again.
You 3 next are on NY list for PMing, along with 2+3 other people.
My springs showed up as well and look great. I hope to put together an MT09R with them this week if I can find the time. I just started some new work, so not sure when that time will be available.
Paypal sent
My springs came today. Thanks!
The taped envelope was intact. The springs look good. I haven’t had a chance to do anything with them, yet.
For my most practical and frequently used lights, I plan to replace many of my spring bypasses with these springs, either singly, or nested. For my highest output hotrods, I’ll probably continue using spring bypasses.
Out of curiosity….what would be resistance decrease with a third, larger spring?
It would be cut again in half.
The resistance I calculated conservatively of the big spring is 10mOhm.
A dual spring array would be capable of 5mOhm, and a triple spring array would decrease even further down to about 2,5mOhm.
However, the problem would be compatibility and stiffness of the triple array, and for me?
Lots of math again 
Thanks for the answer.
I got my MT09R built yesterday when my internet was down.
Overall the new springs are working quite well and are way easier to work with then the bypasses if you have a hot air gun.
Using these springs vs the bypassed spring carrier on the same light showed around a 10% difference in output on average.
The main spring for the driver has to carry the full ~40A of current so it sees a bit more of a drop when that spring is not bypassed but still quite good. For production lights these style springs should work great, 90% of the performance and way way more reliable. I don’t see me doing a lot of bypasses from now on, that extra few percent is just not worth it in most cases IMHO.
The spring tension is also great, although in the MT09R they are taller then the stock springs so getting the tailcap on is a little harder but not a big deal.
Very happy with my order and already thinking I should of ordered twice as many.
They shrink a bit after the first few full compressions so even though they may look big once you realize that it may not be as big of difference as it seems.
Yeah. The small ones do more plastic deformation than the large ones since their wire gauge/diameter ratio is higher, meaning they are stiffer, and require more force to compress to the same height, meaning a higher potential for plastic deformation.
The large ones have no problem with deformation though. I produced them at 13mm since I knew it was going to deform at first compression, and testing them revealed I was right to go from 12mm to 13mm, as the spring lost about 1,0mm.
They did not lose any more height after that, even after 20 full compressions.
TLDR: Big spring is better than small spring in terms of mechanical strength.
Regardless, like hank@ Emisar mentioned in a thread about his the deformation happens once and then it’s pretty well set. It’s fine since both springs were designed knowing it would happen.
When doing bypasses, do you think you’d still get a bit more performance from these springs instead of stock? I just got a light from Dale (DB Custom) in which he replaced the tail PCB with a sheet of copper, put the large springs from this sale on that, then also wire-bypassed the springs!
If you are bypassing the springs anyways I doubt you would notice the difference with using these springs on a pure output basis unless the light is pulling something like 30-40A.
Now these springs are nice and springy and a good size, so in some lights it is worth swapping them out just for that. (the L6 for example, this might allow it to use the shorted 26650 cells without breaking contact if dropped)
Thanks Texas_Ace! :student: :+1:
Oh.
About bump resistance, I can easily say that the Q8 now never turns off with the new dual springs.
No matter how much pressure, or how much “bump force” apply, the light does not turn off momentarily. Which is very nice.
There are also two other advantages to using copper alloys for springs:
1. Bypassing these springs and soldering them is so much easier than regular steel springs because of the lack of chromium oxides.
2. If the bypass fails on a light that use 2S+ battery configs, the spring will still be working quite well and won’t get incredibly hot, and most people won’t notice the difference at all.