I don’t think the car analogy really fits.
Maybe Option #4 fits your car analogy? Keep existing springs, shorten battery tube and issue a statement that cells longer than xx.xmm will not fit.
That’s like saying don’t buy a certain tire, only buy these tires: xx, xx, xx, etc…
Is that what your saying?
There are many protected GAs in the 69 to 69.9mm range, but few longer than 70mm. Thus maximum length should not be less than 70mm.
The light was made to work on any amount from 1 to 4, the springs posing a functional problem shouldn’t be brushed off. The light could have been designed in series if it were to require 4 cells to function, but it wasn’t. Also not everyone bought the 30Qs, a lot of people acquired other cells due to region, preference, or what they already had on hand.
And get a jeweler to laser-etch each spring “BLF-Jozz”
They could become a new standard flashlight component.
“’Every good light uses them. Accept nothing less!”
I know, I know, “don’t let the best be the enemy of the good” — but — Jozz’s springs are significantly better than anything else.
For those curious, the ~300 protected GAs spoken for in RobertB’s group buy measure 69.7mm with button according to the product page.
This is arguably the most powerful budget soda can light to date and all of a sudden we are talking about running it on one battery, I think we all have many other single cell lights we can use in an emergency if that is the reason behind this.
I thought the only problem was that the shorter batteries did not compress the main spring far enough to make contact with the inner spring to share the current load. And due to the high amount of current, it caused the main spring to over heat and collapse?
If this set-up as it is now, in the picture works for the longer protected batteries, then the longer inner spring will work. You could make the inner spring say 1mm longer than the main spring, and the barb on the end of the main spring will keep it retained, assuring contact to the main spring to share the current load.
An example of this, would be the S41 double tail cap spring.
I want a Corvette. Is it ok if I only buy two tires for it? (They are kinda expensive.) Is it better to put them on the left or right side? Can someone test that and let me know. Thanks!
I saw nothing in what djozz wrote or suggested that mentioned any change at all to the battery tube.
I have no problem with the length, 66 to 69mm was just a perhaps figure, nonetheless, my suggestion still remains that “let the organizers of this project decide what is the range of cell length recommended for this light and be done with it” so we can move on.
That’s why I mentioned it. Spring height and battery tube length need to work together to fit the battery length range we want.
If you run shorter springs you need to shorten the battery tube.
If you run longer springs you need to lengthen the battery tube.
It’s a balancing act.
If the current springs can fit 71.7mm batteries and we switch to a spring that will add 1.5mm to the compressed height, then 71.7mm batteries will no longer fit.
Assuming we want to still fit them, it will require lengthening the battery tube about 1.5mm.
On the other hand, if we want to exclude such long cells, we can leave the battery tube the same length and Thorfire/The Miller can issue a statement saying the max battery legnth will be 70.2mm.
So longer springs and longer battery tube fits everything well
Or longer springs only and we preclude cells over 70.2mm
Each choice has their pros and cons.
Springs should only be compressed fully in worst case scenario. I don’t see how an extra mm on the spring suddenly compromises all these long batteries, it just helps out short batteries and compensates sag over time.
On another topic has anyone thought of a way to mount this thing to a bike?
I think i see where you are confused. The spring The Miller was suggesting was not 1mm longer, it was 4.5mm longer.
let’s not make this a bigger issue then it is
No tube changes needed, just the small springs of the double springs that need to be extended 2,5-3mm and it is good
Even in the rare case somebody wants to run on full power with less then 4 cells and using the shortest cells possible the issue would be non existing.
I measured my 30Q BT at 66mm (and had only the metal caliper at hand so did not squeeze it down to avoid short.)
Then I ran my four cells down in pairs, making sure that:
They were on the same springs
Only have it run on turbo, letting the Q8 cool after it stepped down so the springs got max amps the entire depletion actions.
The two heavy used springs (of which we know only the bigger of the two made contact have sagged by roughly half a mm, maybe even less.
The Q8 is working on these two spring sets, working like a charm
Running down the whole set now, and will measure voltage in half an hour or so.
So relax 
the samples work, keep on working after pushing the tricky buttons and TF is aware some changes are to be made.
Maybe for us the phosphorus bronze springs are hard to source in China, I am sure that a single spring out preforming double springs, large springs and such is of interest to Thorfire so we will ask if they can source them and who knows, they need about 6720 for the first run, might be interested to use them in other high preforming lights like the S70 (S).
Even if this is not possible, I did see a Manker double spring solution posted above, this would already solve it and that proves it can be sourced easy in China.
So there is no reason to talk shortening or even lengthening the tube
I am only a few days member and the thread is now very long.
Can someone please tell me when it is time with the order?
I hope I have not interrupted the discussion with this question.
:+1:
Guys,
with all the suggested possible solutions to this problem, how do we proceed from here? Who decides how it is solved? Longer springs, beefier springs, different material springs, shorter tube, all of the above? Shouldn´t we talk to Thorfire first and ask them what they think about it and what they would suggest at the current stage of development? Maybe the manufacturer already aquired the needed Q8 springs or cannot source different/beefier springs on short term or the or the light gets more expensive? Maybe shortening the tube would not be an option because the machines are already setup (i´m just brainstoming here…).
All I´m saing is that maybe the Team should talk this through with Thorfire first before we decide on something?
K.
:+1: … … :+1:
Yes, we are talking with TF now
And FYI, ran the Q8 on turbo untill it was almost too hot to handle, then removed the tube and measured the 4 30Qs as fast as possible, they all came in at 3.85V
My apologies if I made it seem as though your suggestion were under fire. That was not my intention, and I imagine ThorFire and the Q8 development team will accommodate numerous cells.
I’m newer to this forum but I have full faith in the BLF team. You guys are rockstars by all accounts.