The mcpcb is not fixed in place, there are no anti rotation screws.
Head is fine to unscrew.
The tail cap should not be unscrewed.
Change the battery by unscrewing the head.
BTW, the optics and mcpcb are only effected if you try to unscrew the bezel on the head, which is not recommended. This is seperate from the head itself. You might be confusing these two things.
A mountain is being made of a molehill by some concerning the FW3A.
It is the same as any other light:
This is just all normal stuff that applies to ANY light, nothing more.
I sent Neal an email yesterday but haven’t received a response yet. I’ll make sure to request for replacement/return when he does reply, now that I’ve found the problem. This is the first time I’ve taken apart the head like that. It must have arrived like that, since it was never operational.
If you guys need better photos or the original, unedited photos for reference in this thread, I can go ahead and post/send them to you guys!
Alas, those used to be a feature, which some of y’all are too young to recollect.
EDIT: djozz described one here, around the time the assemblers forgot what the holes were for; they started showing up misplaced and eventually not even threaded, then quit appearing at all.
Circuit boards used to come with notches, the screwheads appeared in the notches, and the board wouldn’t turn.
Saved a nickel apiece by eliminating that step of the construction, perhaps trusting the thermal goop to be glue.
Ah, I know I’m a fossil remembering back when they used to build these things by hand.
This is sarcasm, in case anyone thought he was serious. :partying_face:
Wait… by “bezel” I understand this to be the front most piece on the light. You need to remove that to get access to the optic. So why would it be not recommended? I’ve removed it about a dozen times thus far to experiment with different optics. No problems. I do not get any MCPCB rotation going on.
> anti-rotation screws
as described by djozz here: My impression of the Sofirn SC31, almost right - #4 by djozz
This front bezel gets a lot of folks in trouble. It depends on the light, though so some companies just glue it shut. Some lights have optics that sit on top of the mcpcb and if the optics get twisted you can dedome all your leds.
In the case of the FW3A, removing the bezel can twist the wires off the mcpcb. I didn’t know this was a possibility until just now. So we should all use caution when loosening and tightening the bezel and it’s probably a good idea to apply some downward pressure on the lens to keep it from rotating.
It’s like TK says, the more you take a light apart and put it back together the greater the chance you’ll break it. 
Ah, just noticed Berkley………… spent a few months there in …… probably ‘68. ’Spare changing’ on Telegraph Ave and sleeping in Peoples Park in a ’59 Pontiac someone gave me in Huntington Beach. Those were the days
Berkeley was interesting back then. I still remember going to classes with all the National Guard and police walking around. And being teargassed was…….interesting; especially when they used a jeep spraying teargas out of it and being stuck in traffic.
I guess “interesting” is one word for that…… ’sucks’ seems more appropiate to me however. 
Very true. Back then it was awful and really was a terrible experience. But now it doesn’t seem like it was all that bad since one tend to forget how bad things were long ago.
I won’t even go to how “interesting” it was getting shot by rubber bullets or how fast one can run when being chased by people with big clubs who had legal authority to use them :weary:
Ouch…. “rubber bullets & big clubs” could get “interesting” real fast!! 
That really would “suck”.
I guess looking back…. time does put a different perspective on things.
I figured that since the front bezel FW3A is attached using external screw threads on the body, unscrewing the bezel won’t affect anything internally. The counter-clockwise rotation to remove it might cause the front glass to rotate for a small amount, but the optic definitely doesn’t move. I pop it out, then put a replacement optic into the 3 peg holes, lay over the glass, then screw down the bezel. Nothing internally rotates. But I hear you, that it may not be true for every assembly.
I will follow your advice, though. The next time I do it, I’ll take a toothpick to the MCPCB and check to see if it’s well anchored in place or loose. I definitely don’t want to end up torquing the wires and cause them to detach!
Hey… if you have not had any problems your obviously doing it right. I wouldn’t change anything. (And I did not suggest a “toothpick” for anything either… )
All I am saying is just because you have not experienced a problem does not mean someone else will not experience it.
I have found that a little bit of pressure on the glass lens with my thumb when removing or tightening the bezel on lights where the MCPCB can rotate is enough to prevent a problem. (after the first time I ripped the wires loose on one)
/\ ……
I have double check to make sure i’m not in muggle mode.
I’m unable to go into Group 2 now.
When i perform click, click, hold ……it just respond by one dim flash/flicker and goes off.
I’m able to go into Group 2 the first time when i received this light and i was playing with all the Group 2 mode (candle, bike flasher, party strobe, tactical strobe, lightning storm). The last Group 2 mode i used was lightning storm.