Thanks mate 
Not very accurate or scientific but it was an experiment 
I love it! Does any configuration work with common 20mm optics?
Well, the optics I have, per se, don’t fit!
However, if you use some holders below the optic, it may be possible. But only the FW1A Bezel. With the FW3A bezel the optics (even some smaller ones) don’t fit.
The optics - at least the ones I have - are smaller in diameter and, specially in height, than the reflector. So, to make them fit by their own, we’d need to add some extra lenses above.
Or, depending on the type of holder, it may fit with some mods.
See the black holder (this is an old photo)? That one matches the height of the FW1A reflector, but it is larger, so it needs to be filed in diameter to fit into the bezel.
Also, one needs to be careful when using these holders and optics due to 2 things:
a) the beam that it will produce, specially it if it is a narrow beam optic and XPL-HI Led
b) the possibility to inadvertently rotate the holder/optic and damage the LED, either it has a dome or not.
A “pebbled” (hive) optic or a “frosted” optic will produce a very wide beam, no hotspot, and homogeneous beam. A 25º or 45º optic…may produce a horrible beam.
Check this hold thread where I made some experiences with different optics and the same led type I have in my FW1A (XPL HI).
Hope this helps!!
Did anyone said sh!tt! tail switch booth.. ?
Well, dare guess..
Perfect fit!. :)
Cheers!
Hum, does the light work with that configuration? 
Also, is it waterproof?
I mean…I tried using a simple normal “rubber” tailcap as the ones we use in almost all flashlights, and it didn’t work well due to the space created inside, and due to the contacts between driver, host, tube, etc,.
I am really searching for a way to avoid accidental activation (and still keeping the button silent as it is now), but I haven’t found one yet (with the materials I have)!
So, I’d like to know more on this, please! Thanks for showing it
Well, it does work perfectly fine as far as I'm concerned and it has a better tactile feel and no more wobble or scraping between the tail cap and the metal boot.
Regarding waterproofing, I don't think that is the case any longer, as the metal ring sits on the metal (well.. aluminum) tail cap with no seal. I'd say, gluing the metal ring on the tail cap would bring back at least water resistance through.
Regarding accidental activation, it's a bit more recessed, thus more reliant, to say it like that, but I still wouldn't bet my nuts on it in every instance, say.. having stuff in your pockets other than the light itself.. or having it in a backpack (although, having it in a backpack wouldn't really be a situation where you would have a good reason to keep a light unlocked and ready to.. fire)
Cheers!
Before discovering the o-ring switch mod I simply just removed the metal portion of the switch and it was great. Maintained waterproofness and no switching issues. It’s not very pretty, but I’m sure someone can get creative.
Thanks for your reply I guess when I order a D4 I will get a spare switch to try it on the FW3A, even it it may have some issues there! Nice setting as it is
Thanks again!
This would've likely ended up being my solution as well, shouldn't I've accidentally had a spare D4V2 broken head that I could strip the ring and rubber boot from. In addition, probably I would have tried to fill the gap left between the original rubber boot and tail with another o-ring.
Another "quick fix" for whomever might be interested :)
Not sure how happy everyone is with the current FW1A OP reflector and the beam profile, but I know that I, for one, surely dislike it with a passion (well.. I highly dislike most OP reflectors in general.. )
Thus, here goes:
The reflector I've used is an S2+ SMO reflector, the one without the "ribs" / "heatsinking cutouts" on the sides, so it would go in just perfectly, not overlapping with the body threads.
This is the reflector I've used: (the SMO version of it)
As an added bonus to the nearly perfect beam profile (for my taste) there's also no more outside ringing around the beam as the glass now sits about ~2mm high on the reflector, thus no more "double reflection" of the emitter into the glass and then back into the reflector (there is still some, at a different angle, thus very hard to even spot if the conditions are not right and not looking for it specifically)
[EDIT] I've also had to use a very slim shim underneath the gasket to get the proper height of the reflector on the emitter (for each emitter/reflector there has to be a bit of experimentation) in order to get the perfect hot-spot. My shim was a piece of plastic sheeth from a package, about 0.2mm thickness I'd say as I don't have a precise tool to measure it.
[EDIT 2] Forgot to mention.. The S2+ reflector's OD is obviously smaller than the FW1A's bezel ID, thus I've also had to use some "filler" in order to keep it centered - in my case, as I don't have any means of creating "custom parts", I've just used some tape to wrap around the reflector up to the necessary OD, then cut the excess tape width extending further down from the reflectors bottom lip.
Cheers!
Any pics of the difference in beams?
Unfortunately I don't have a good way of taking any good pics of a beam, they would be overexposed and not much difference could be seen in the picture compared to what you're actually seeing in real life. I might try tonight when I'm back from work, but I don't think they'll be any good.
[EDIT] Also, I forgot to mention, my FW1A just got an emitter swap and currently running an XP-G2. (well, along with removing 4x7135's and the FET) Now I'll just need to find some time and mod the code and reflash it to reflect the changes. Other note would be that the XP-L HI sample that was originally in my FW1A with the S2+ reflector was giving some egg yolk effect in the middle as some other XP-L HI's, ex. the one I've had in my GT Mini which then got replaced with a different one which I don't remember what it's origin was, but has nearly no egg yolk effect. So I'd imagine with the various bins and tints Lumintop had no option than to go with an OP reflector.
Cheers!
[EDIT 2] Just to avoid double posting..
The new XP-G2 emitter:
Beamshots @4/7 brightness lvl. just to keep the exposure in check.
Cheers!
I agree with 80T about the beam profile in stock reflector but sure as hell i like S2+ reflector.
Need to try this!
Can you provide more info on removing the fet and such? Was there a change in firmware?
The FET and the 7135's were simply removed with a soldering iron - desoldered the wires on the emitter > removed driver from the head > desoldered 4 7135's on the spring side and the FET on the other side
As far as firmware is concerned..
No, I haven't yet got around that, but I've done the hardware changes in advance given that I was planning to upgrade the firmware on this light regardless, as it's an older version with a couple of missing features.
Thus far, the ramping or the discrete steps are obviously not linear any longer and I'm going to have to compensate for the difference in going from 1 + 7 + FET on 3 PWM channels to 1 + 3 on 2 PWM channels.
Another temporary caveat with the missing FET, is that the Turbo is no longer working because the 1 + N 7135's are both 0 (shut off) at the 150th step leaving only the FET fully open to take over all of the current flow.
This is going to be an easy fix, by editing the steps of the 2 remaining PWM channels and adding the corresponding 150th steps values - hard part here being calculating all of those steps to get a visually linear ramp.
I know there's already a python script somewhere in the code, but so far I've no idea how to use that - I'll probably end up finding an online calculator or something (maybe even something taking straight on py scripts)
I'm thinking of further editing the code and use the 3rd PWM channel (originally FET) as the output for an RGB AUX digitally addressable LED (that is if I can find one that runs on something around or lower than 3V)
This mod would be pretty much the same as what Lexel did for the FW3A (can't recall which PIN did he used for that but it's easy to find the thread on BLF) only I just want 1 x LED and a hole drilled in the light's head.
What I want that AUX LED it's mostly R/G as battery indicator (G/Y/R/Blink R), and maybe the B (since it's already there and addressable.. ) used to indicate/blink some other special states.. Say.. locator indicator or..
As a standalone mod, I wouldn't recommend going for swapping the emitter to a lower power one and removing the FET and any 7135's - the advantages are minimal, mostly cosmetic and the output is reduced.
If the beam pattern and the reduced power draw are of a great importance to you, then, if you're willing to edit & reflash the firmware, then, the mod would have meaning. If not, it's just a waste of time and effort.
Myself, yes, I'll take the reduced power draw, I want to edit the battery voltage cutoff to something like 3.2V and I.. CAN NOT STAND the smooth, undefined beam pattern of the original OP reflector & small emitter.
I'm kinda throwing myself head forward on the firmware side of things here and I'll have to reflash the light anyways, but I'm not sure if I'm going to be successful in achieving all of my goals regarding the editing part.
Now, having the Turbo working, that's easy, finding the right steps values for a visually linear ramp ? Idk.. Getting the proper code edits to have an RGB addressable AUX LED to do what I want.. Again, Idk.. :|
What I know though, it's that I'm willing to give it my best try. Whenever I'll have some spare/quiet time that is and the proper mood for it.
Thanks for the detailed response! I look forward to hearing how it goes!
So.. the deed was done :)
Took me a while to calculate the ramping steps for the two channels, but for anyone interested swapping in an XP-G2 (1 + 3 7135's ~1400mAh) here are the PWM levels:
#define PWM1_LEVELS 1,1,1,1,1,2,2,2,3,3,3,4,4,5,6,6,7,8,9,9,10,11,12,13,15,16,17,18,20,21,23,24,26,28,29,31,33,35,37,39,42,44,46,49,51,54,57,60,63,66,69,72,75,79,82,86,89,93,97,101,105,109,114,118,123,127,132,137,142,147,152,157,163,168,174,180,186,192,198,204,211,217,224,231,238,245,252,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255,255
#define PWM2_LEVELS 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,1,3,6,8,11,14,16,19,22,25,28,31,34,37,40,43,46,50,53,56,60,63,67,70,74,78,81,85,89,93,97,101,105,109,113,118,122,126,131,135,140,144,149,154,158,163,168,173,178,183,188,194,199,204,210,215,221,226,232,238,244,249,255
#define PWM3_LEVELS 0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0,0
These are the PWM levels considering no further modding would be done, PWM3_LEVELS being the FET.
Anyone happen to know the dimensions of the FW1A reflector?
I’m curious if the khatod PL114506 optic will fit. I’m not a fan of reflectors and I already have an FW3A.
Anyone seen a GITD oring for the FW1A or know what size oring is between the lens and bezel?
23mm OD is for sure. Diameter of 1mm will need confirmed by someone else.