Caleb, sorry but that was back before I got hurt and had surgery… my memory is bad enough without that kind of thing so I really lost a lot of time memory wise, can’t remember doing things but see the light in front of me, wow, how’d that happen? I probably have notes on it somewhere, will dig around and see if I tested it on the stock driver. I just don’t recall.
Dale (or anyone else with batch 2 lights) can you please confirm for me the type of screws in the Q8? Your posts in the other thread said that the tail and driver screws are both M2.5, are they button head or wafer head? Is the reflector screw also an M2.5? I want to update the “Checking your new Q8” post with batch 2 information.
Round button head phillips, M2.5 x 5mm,
2 on the driver, 4 on the spring pcb at the tail
The reflector has one large screw in the middle and 2 small screws at the perimeter, going through the emitter shelf. These serve no purpose to change as they are not in the circuit.
I believe screw size differs depending on first batch or subsequent batch.
First batch uses M3 x 5mm screws for the 2 driver screws. That is what my 2 first batch use. (they do use M2.5 for the tailboard). That is where TF messed up a bit, and used M3 but did not bore the driver out to accept them with side clearance. The head was drilled/tapped for M3. It would appear they changed the subsequent batch to use M2.5 for the driver if Dale has M2.5 there on his.
Where do you order those from?
Great, Lexel, thanks a lot!
Arrow.com - insane free 2 day shipping, but they do charge sales tax. It's an awful site but just search for the part #'s.
Well I’ve never been too into hot-rodding but this light… I’m not sure what it’s practical use is except for making big smiles. And now 2x the power 
?
So a couple of questions DB. Do you think the brass screws are needed if you just bypass straight under the screws with braid, stranded wire, possibly even solid wire, or maybe lugs?
Now about those xp-l2’s you put in. Wow, 2500+ lumens per led? I’m a little surprised that’s possible. This is mostly due to their lower Vf? Are they likely to burn out? Are they blue? low cri? 1C is pretty horrible isn’t it? It only counts if the extra light makes me smile more, not less.
I’m assuming that using high capacity cells won’t get close to this. Problem is though, I already invested in high capacity cells, and if I bought more cells I’d have to buy another light too. I never thought twice as bright would be possible without using some horrible fat floody led’s.
Who is gonna be first to mod the Q8 with xhp 50.2’s and what all is it gonna take?
Thanks!
Flintrock, I didn’t know it was possible either and it puzzles me to be honest. I’ve used the XP-L2 in a C8 and others where I saw 2100 lumens from a single emitter, but the intensity from this Q8 is just unreal. Our living room is 18x20 and a ceiling bounce makes the room seem like the roof was lifted off at high noon, it’s ridiculous. I had my wife close her eyes and then double clicked Turbo shining it near the center of the room at the ceiling, she thought I’d pointed it at her, it was that bright even with eyes closed!
The XP-L2 V6 1C emitters are a bit on the blue side of white, not horrible unless you compare it to the stock V6 3D’s in XP-L HD form, but as you say, the sheer chits and grins are worth some trade-offs. 
I can’t say what the Q8 would do without some of the steps I took, I built it up one step at a time and charged cells, re-measured output. The final run was 3 steps, 18ga wires/new LED’s/new MOSFET. It took a 3000 lumen jump doing that last step. It is what it is, if some XP-L2 1D’s were sourced it shouldn’t be too bad, just a matter of what you can find really.
The early Q8 proto I modded with XPL2 V5's, think 4000K though, and only got in the "6nnn" lumen range, but didn't change the FET, and overall, probably not as good as the resistance path of the production Q8's - uses a brass driver retaining ring, thinner MCPCB, not sure of the tail PC mount, stock steel screws, etc.
So it's a bit of a different animal - deep NW tint and lower bin LEDs may be big factors.
I’ll try this one with button top 30Q’s and see what difference there is.
My number 3 Q8 is on the mail truck for delivery today, will be able to compare side by side. Who knows where number 2 is, lounging by a pool somewhere I guess.
Hi Tom E., you reccomend 20awg wires,but i only have 18awg and 22awg,which one would work verter? Thanx
Well I don't think you'll lose much by using 22 AWG bypasses - 18 AWG I would think would be hard to work with, plus the way I route thru the base of the spring, the 18 AWG is much thicker so you'll lose spring compression - dunno might help by improving bump protection --- your call.
Ohhh - the above mod was before I started using brass screws, sanding down the MCPCB/shelf contact surfaces and using MX-4, swapping the FET, and replacing the stock LED wires.
Thanx, there are so many mods,and threads,just to hard to keep it up, would be nice so each different mod would be put nice and clear in one individual thread - my unit camed in the first 500 batch and comparing it with the srk,i am kind of disspointed , definitely dont reach 4,5k - so,until would be a clear mod and places to get the screws etc.,i will do the basically
Out of the 10 first 500 Q8's I've tested, the lowest was about 4,700 lumens on good 30Q BT cells. If on good cells it's under 4,500, then there's something wrong there. You could have a bad driver mount or glue/contaminant where the tail PCB mounts to the shell of the battery tube, or both issues, just a bit worse than most.
If you tighten up the battery tube hard, and can notice it brighter, then the driver contact is suspect -- I've reproduced this on almost every first 500 Q8's, you will always get more output on tightening it up hard.
There was glue under the battery driver,besides 3 of the 4 screws weren’t tightened,the lastima one super tight with lots of glue; just polished the body where the battery driver seats (dremel with very fine sand paper),even though right now,don’t have the 1 1/8 drill etc
Just did It,be4 the mod i could have done 3 x 3minutes on turbo holding it in my hand,right now,3 minutes burns my hand; just tried to burn apiece of black cartonboard in about 20 seconds smokes a los,but to hot to hold it anymore
I didn’t see any need to do all the polishing, the springs will be in contact with the cells and the back side is hidden in the tail cap, didn’t smooth off the edges more than a light file work to get rid of burrs. But Kawi, that sure looks pretty even if it’s hidden.
I had planned on doing this for a long time, was surprised to see it come up and other’s did the same before I ever saw my first Q8, even more surprised that it didn’t make more than a 100 lumens difference. Might be more in the end with other mods stacked on it, don’t know.