Jason, it’s not me you’re arguing with as it was Comfychair that taught me that technique, as I stated.
I would rather, as I’ve already shown, solder a copper disc so the solder doesn’t wear down on the brass contact ring.
I don’t argue, just disagree with what was said.
Comfychair is very well respected, but it sounded like his method would cause the main battery to get very hot. That’s not good.
More than anything a lot has to do with how thick and big the contact is that your blobbing not all batteries have the same size and width contacts, so your time limit of 5-10 seconds might be good on some not enough on others like the Big Batteries that I use. I’m more than careful because 90%of my lights are 2X 3Xand 4X series lights. 32650 26650 26500 26350 batteries have a larger, heavier contact then 18650’s, this is from my experience.
Big difference between saying what you might know, than actually knowing what you know from experience! I’ll stick with my little T-18 tip, you rock on with your biggest! 
Are you talking to me?
I suggest no more than 3 seconds. I can add nice big solder blobs to a 26650 in about 3 seconds, then quickly cool. The battery below never gets warm.
Yep! Then your an Ace! 
4 seconds for me!
Hello again,
Would like to be put down for one more Q8 please, for a total of two.
Thank you.
4 seconds, huh? Must be that small tip your using. Go one size bigger and you’ll cut your time by 0.73 seconds. Lol 
Seriously though, I just want the new folks who have never done it before to get it right their first time. I may do a quick video showing everything, except I don’t have any cells that need a solder blob.
So, um, what would a new run of the phosphor-bronze springs come to?
And can we convince any innovation-friendly flashlight retailers, hmmmm, rmmmm, to take on some stock of such springs?
And could the rest of us pony up a group buy for some?
I wouldn’t mind having a several dozen of them on hand forever, for improving my old lights and other battery-containing products that have cheap springs now.
Should I ask Richard if he’d be interested in laying some stock on some nice springs?
I haven’t solder blobbed a LOT of cells, but I’ve never had one get warm below the top end. Different strokes I guess. I didn’t say to repeat small blobs while the cell was getting hot, it’s the delay between applications that allows it to stay cool actually. Anyway, technique is everything, as with most things. I watched Old-Lumens vids on stacking 7135 chips and found his way horrible! Tom E does a nice stack on those, but I’m sure he does it differently than I do and Scott also probably differs yet again. I’ve only done a couple hundred Qlite style lights so I’m probably still on the learning curve.
Sure would be nice if we could grab a bundle of these springs for stock. Please try and I’m in
Well here it is well past bedtime and as always 100+ posts to read in the thread to catch up (yes, I’ve read every one from the beginning). Still n email updates. Onto business from where I left off
Loving the beamshots- the beam pattern is perfect to me, just what I wanted it to be. Nice pics on parts being discussed and complete teardowns.
Springs, ah well. As a “Pro” procrastinator my workhorse BLF A6 is still saddled with the bump-mode-change disease due to a weak spring I haven’t replaced. Beyond bloody effing annoying :rage:
So the first thing a spring (or multiples thereof) must do is always be stiff enough to stay free of this disease . The only way to achieve that is large enough diameter spring wire(s) which will also assist in carrying current.
Next is that if there are multiple springs they all need to make solid contact at all times with any cell the light will use. Otherwise the long spring can overheat and sag and there’s the current loss that incurs too. I personally don’t care whether there’s one spring or ten so long as the light always works well and gives something close to the outputs we’ve seen so far and keeps doing that. Team Q8 knows what it’s doing and is aware of the issue so in the end all will be well.
Cell numbers doesn’t seem to be much of an issue, The Q8 can probably work fine on one cell without overheating the spring(s) if you use only lower modes. A simple warning in the instruction manual solves that problem. Besides, nobody buying a 4 cell light should have great expectations of using less than 4 cells. Can the Q8 do fewer cells? Sure, but it’s not meant to be used that way on a regular basis and if you want a 2 cell light buy a 2 cell light . In an emergency you’ll still have a very usable light with one cell so no loss really.
Cell length is a can of worms, with many lights on the market not being able to use too-long or too-short cells right this very moment. What is important here is that all of the recommended high-performance cells work without a glitch even if that excludes other cells. On protected cells they are not normally recommended for high-performance lights because most of them will not deliver the high amperage needed here, so if the longest protected cells won’t work then the Q8 will be like many other lights already are. 1/10th of 1% of the buyers will cry, but they’d find something to cry about anyway. Read the instructions and use the recommended cells . Still, let’s aim to accommodate as much variance in length as we reasonably can while we cuss under our breath at the people who have strayed so far from the standard cell length as if that didn’t matter. How you achieve that might be problematic if TF has already bought a stock of springs for production, so asking them about that would be a good place to start . Changing the battery tube length slightly should be easy for them to program for.
OK, I gotta get some sack time so I’ll drop back in when I can. Everyone keep up the good work and the comments from the peanut gallery too. Looking forward to reading them all in the next round!
Phil
I can’t agree more. FIRST I have to say that I think Thorfire should have realized this was a problem and used stiffer springs or thicker gauge wire in them to begin with, but if they cannot change to better springs, then we should make the tube shorter. Every point you make is true, the most recommended and used high performance cells should be made to work with the light, most long protected cells don’t have the amps this light needs so focus on cells like the 30Q and 3400mAh Panny’s.
I have a question here for you guys considering all the talk of “solder blobs” - I knew people did it obviously, but it hasn’t made sense to me … what’s wrong with using something like these?: https://www.fasttech.com/products/2157805
They can be held down by these: https://www.fasttech.com/products/2157503 when you put new wraps on.
I’m not sure if they could be soldered on, seems like too much metal to heat up the battery with? Is that why you don’t like them, too much resistance due to not being soldered on?
They just seem safer and easier than solder to me. Isn’t this how most “button top” 30Qs are made? By resellers putting these and clear wraps on top? (Photo of this here: https://www.fasttech.com/products/0/10002357/6691702-authentic-samsung-inr18650-30q-3-6v-3000mah )
Please correct me if I am wrong.
Soldering these button tops is reale hard. I have tryed it. They can only connected with solder with verry much heat. It stays many minutes till I got solder connected to these button tops. After that I have soldered them to the cells.
Only stick them to the battery is too less connection for me, I think.
I wonder how hard it would be to preheat one first, then quickly move it to the battery and solder … I know the solder would start flowing much faster.
Sawmaster and Nil, do you realize the most amps this light can pull is 5 amps per cell when used with 4 cells. This is well within the range of protected cells.
Since a longer spring can accommodate all short and long 18650 cells there is no reason to exclude anything. Only if Thorfire chooses to stick to the current spring height will we be forced to exclude the really long 70+mm cells.
OK will update list later
No the Q8 is not ready for order, no PM is send on it.
We need to get the springs right.
The currently used bigger spring of the double springs is not so big and preforms pretty OK
Taking Djozz sizes of his springs into account we would need a single spring
Thickness 1mm
Base diameter 10mm
Top diameter 7mm
Height when installed 12mm/13mm
Right?
Those tops are designed to be tack welded to the battery. There are special machines that pulse electricity to quickly weld them into place.
You can’t just use a wrapper to hold them. They would rip right off when you screw this light together.
On a different light, that uses a single battery, you might be able to get away with using a wrapper to hold them since there is no sideways or lateral forces involved.
As far as soldering them, I’m not sure. I’ve never tried that with these discs. If you apply flux to the disc and pre-tin the bottom (heating it up as well) then flux the battery top, you might be able to get them soldered together pretty quick. Like under 5 seconds maybe. It seems possible.
That is … exactly what I said.
With those lateral forces you mentioned I am surprised even a solder blob stays on, I’ve seen “good welds” come off smooth/solid/flat surfaces like the top of a battery before, I don’t really trust it and would rather not.
I already have some of those tops I linked so I might try preheating one, adding flux/solder and seeing if I can get it to stick to the top of a cell without too much heating of the cell itself.
Also, how does Fasttech make those button top 30Qs then? They obviously have new/additional white insulators on top with a new clear wrap on top of the stock/factory wrap, I do not think Samsung makes these stock (why would they have additional insulator/wrap if they did?)
Someone else is adding the button top? Has anyone disassembled them? Are they using this “electric welding” you mentioned? Sadly getting Fasttech to ship batteries to USA is basically impossible anymore …