If anything, I’d work on trying to dissolve it but dunno what the “glue” is made of nor what’d dissolve that and not everything else inside.
If its heavily gleued only get massive heat fast to the connecting area helps,
if done right the glue melts before you overheat other parts of the light
Holy Cats! You sure went to town measuring everything… thanx!
Yeah, I guess you really do need to take both dimensions into account, diameter and depth. Too loose and it’ll rattle around; too tight and you won’t be able to screw it down all the way. An O-ring can only handle so much slop.
In the S2+, the pill just screws in and in and in, ’til whatever’s in there stops it. So a few mm play is no problem.
It affects the length of the space the cell fits into, but springs in the tailcap and on the driver pick up the slack.
That last reflector with the black “shoe”, you might be able to shave down the outside diameter just a smidge to get it to fit. I had to kind of force-fit the shoe into the S2+, and let the threads do the shaving. Nice and snug, yet still removable.
What I wouldn’t want to do is stick a nekkid TIR into the reflector. Stray light leaking from the TIR, hitting the reflector, coming back into the TIR, might muddy up the beam in unpleasant ways.
Or I can end up with a desert-tan version of the F1…
Hum, I had to put the F1 in a table vise to get it real tight, and the I had to use a big pipe wrench to make it unscrew! (1st, the part of the battery tube, 2nd the bezel).
The thing is: I was not trying to protect the host (body, “switch” or head) as it was already damaged.
But I guess that even using foam or any kind of tissue wouldn’t be able worthy because then I would lose the grip and the wrench would rotate without turning the part I would want to.
Also, the strength applicated also provokes deformation of the tubes, especially on the bezel! To avoid this, maybe the solution - if worthy - would lay on using a box or socket wrench (and a protection of ruber, tissue, or whatever) inserted from the front/top of the flashlight.
But even from there, I guess that it would provoke deformation or even a lens breaking.
It is really well glued, and in fact, I think that it would be a real waste of time and would damage the anodization and, eventually, the threads. But, I was not kind and just used brute force, no heating, no solving things!!
Hum, maybe it worked, maybe not! When I inscrewed, the glue was “dry” but even then it was hard to rotate the parts. In the head, putting a big amount of heat, maybe it had impact on the LED or the wires, maybe not. (The host is really strong!!!)
I heated it up some times, and couldn’t get any results but I was using a “jet” lighter, only 
[quote=Lightbringer]
You’re welcome :nerd_face:
Hum, there’s a huge difference from this to the S2+ in terms of head and space. On the F1, a TIR lens would have to be specifically made for this, otherwise we would get no protection and it would, eventually, rattle!
Even the last one I used (black), shaving it on the sides would make it fit in diameter, but there would be half of the bezel to fill (in height) because it is too long and the lens is short!
The S2+ can easily take a TIR if the size is appropriate. On this, I don’t think it would work.
Also, for this light’s characteristics, I think it would be a waste! The bezel is quite nice and make a good work!
The only thing that is annoying is the AR coating of the lens, that should not make the tint look green. That would be the thing to change.
And of course I wouldn’t use a TIR inside the reflector, this as more a example to show proportions and measures 
With or without holder is the only way possible 
I agree that massive heat is one of (if not the only) way to unscrew the head.
I am interested in opening mine to change LED.
If anyone finally gets an easy non-destructive way…. let us know
I used heat to open some lights my Nitecore P12 comes close to the F1
When its hot enough you can unscrew the bezel with you hands, just used a towel to protect me from burning my fingers
Wish I had a tool to produce lots of heat 
I wouldn’t have damaged it so much…
What’s done is done, no turning back!! I guess we all learn from some mistakes and improve from them
Though, I still say: with the F1, you may need a loooooot of heat ! And beware not to damage the pieces (the gasket between the LED and the bezel is plastic, not aluminium as the rest of the light… So, maybe it can melt internally, I don’t know…
If you heat up small areas fast enough internal parts like driver and Gasket are usually OK
But some o-rings got too hot
Last light was Klarus G35 I used my autogen burner with oxygen bottle, but you have to move it fast or you do change the eloxal color
I don’t have those tools unfortunately I just have a torch butane lighter, what is not enough for this!
Still, I tried heating the part of the tube for some minutes, moving it around, without burning just a small space. I wear some thick gloves to move the parts if the tube, but it didn’t move a single millimeter …
I must say the the colour didn’t change, it remained black. Maybe because I didn’t put it into much heat, I don’t know…
The new F1 has arrived :partying_face: I missed this one 
Thanks Gearbest for taking care of the situation and for sending a new light :+1:
C'mon fellows, submerge the flashlight in a little pot filled with white spirit and/or straight gasoline. Wait until threads roll. In case of emergency, boil the pot a bit. 
Sort of like dedoming emitters. 
Thanks, Dear. As a representative, I am so glad to share the happiness with you all, hope you will like the item.
Nice weekends, and thank you for your support all the time, do not forget we have a giveaway here, we will announce the winner hours later: Gearbest Giveaway: Sep-Super Bumper Harvest Festival
Not to be a ‘negative Nancy’, but this case makes me wonder what to expect when mine gets in, and why it was only $12.99…
O well, we’ll see. 
I recently got some TIRs in from, you’ll never guess: Deal Extreme.
They’re slightly larger than 20mm and might just be perfect for the F1.
Link: http://www.dx.com/p/21mm-led-acrylic-lens-for-flashlight-5-pack-41690#.WbyRyNfk6PI
They’re quite nice. Tight beam and also a circle of ‘spill’.
I’m still getting to know them better, but they are a little larger than the average “20mm” TIRs.
Maybe worth a try.
Thank you Gearbest :partying_face:
Thank you for your advice about TIRs. 12.99$ is actually only the price for Big Promotion to thank you for your support:) max per order: 1 piece.
Do not worry, we just set the special codes for our members:P
If you have any need about products codes, we will try our best to set codes for you, of course 
@Gearbest:
When you want to use modern Cree LEDs like XP-G3 and XP-L2 you will have to use TIR optics in stead of a normal reflector, because the modern Cree LEDs have some serious tint shift issues, very visible when you use a normal reflector.
(I proposed the DX TIR to MascaratumB because he likes TIRs too, and he could fix his damaged F1 with it.)
So kind of you, Dear Jerommel, to give us advice and kind help here, thank you for thousands times :+1: I will sahre the info with my team, thank you.
I think at BLF we should help eachother, even people like you who take all our money.
Sorry Jerommel, I guess I missed to answer you before :person_facepalming:
About to expect of the F1, I guess you can expect the best! I’m pretty sure that mine was a not so good item, but the new one seems to be in perfect conditions (NO, I did NOT test it in water NOR will I do that 
)!
About the TIR lens, I do like some, specially those that produce a more floody beam (pebbled) and some with narrow beam, but not all.
The one you showed in the link doesn’t seem to be the case. Last month I got a SS steel light (3xAAA / 18650) with a TIR like that , and this is the beam:
So, nowhere near the beam of the F1! Of course this light had a different LED, but that beam is not so good! I the modded the light, putting in a XML2 + ConvoyS2+ OP Reflector + S2+ AR Coated Lens. Now it works fine :sunglasses:
Also, I don’t know if the F1 bezel would take that lens inside if it. I can’t measure now, but later I’ll do it and let you know, in case you wanna do some changes!
Anyway, thanks so much for the suggestion and sorry for the late reply