Well….unfortunately, ppl are usualy boored and ignorant - when they have nothing to do and bored: voila,they start messing with their flashlights( and other stuff), wondering whats inside: thats why they are gluing - i can understand that, completely 
Yet, its bad for us, realy
It would be enough to put such a seal sticker on a driver screw just machine a shallower pocket in the retaining ring Astrolux uses
on the MCPCB for example they could use some seal paint on the soldering spots and screws
Lexel : companies just dont want and like user to mess with their stuff, especialy after they broke it and start whining about the warranty 
And yes, americans and here in the EU: we are in Love with the whining, the louder the better - believe me, i was working for Toshiba EU for 10 years, i have seen alot
That would work for the driver, the real issue is the bezel, I can’t think of a way to put a tamper seal on that.
Although even on the driver one of those stickers could be an issue since they look electrically conductive.
Blue locktight could work, anyone actually tried this in the real world?
Well, I do not like glued lights but if I like the light a lot I will buy it.
Heat is usually “stronger” than glue
Blue loctite can still be real pain to break free if its applied liberally. A drop might not be so bad but if the threads are covered it takes quite a bit of force to break free. The red is the strongest with blue being the second strongest. I would think the purple might be the best for flashlights or maybe the green.
The blue in my opinion, is to strong to break free somewhat easily. I have had lights that used the blue generously and it took alot of force to break free, it’s doable but it takes way more effort than I would like, especially if your trying to use a glue that a light could be disassembled in the first place.
I still would like no glue or press fitted parts at all if I had my choice.
I do not mean stress relief but more general damage prevention. If there’s a warranty claim - there’s damage. That damage is either factory fault or light just being unable to survive the way user handles it.
In a way - there is a difference different damage from misuse (including disassembly) and from regular use. However I believe any item should be robust against at least basic misuse - and anything more than basic is good to have. Preventing misuse is a valid way of increasing robustness.
As to securing bezels…
I have a feeling that retaining-ring style bezels (like Utorch S1 Mini) that you can lock into only from the inside are easier to secure.
One that has a smooth wave shape on the inside would be impossible to unscrew with needle nose pliers or similar things. But a tight-fitting tool could provide enough torque.
ADDED:
A bezel is basically a screw. I see that there are several ways of making tamper resistant screws:
- breakaway head
- Doesn’t seem applicable, finish would likely suffer
- one-way screw
- can be removed by glueing something to it and then replaced with a distinct removable bezel
- I think it could work but seems complex
- can be removed by glueing something to it and then replaced with a distinct removable bezel
- custom tool required
- yeah, as long as the tool can be used for many lights - that’s actually cheap
- glue them
- oh well…
Yeah, I kind of figured that would be the case with blue thread locker.
I have never tried purple or Green though, any experiences with these?
or some form of heat releasing glue that would release under ~200f degrees.
Pain yes… But not too hard if you heat the parts up. The idea is to keep the yo-yos out while allowing those that can the ability to mod.
I think FF just says that to scare people. I told them my 219B E07 went bonkers and they offered to ship me a replacement without questioning whether it’s glued version or not.
Loctite: blue (medium) and green (capillary) thread lockers I had some success by heating the screw with my soldering iron till I smell the distinct smell of ‘loctite’. Have been able to remove brass shallow cruciform screws.
Have seen screws / assemblies marked with a dab of colored ‘lacquer’ indicating disassembly. A sticker warning warranty voided if tampered on box or product label.
Some of my purchases / givens had un-removable bezels. I wrapped a few layers of aluminium sheeting and heated with a propane torch. The alum acted as a flame guard and transferred the heat. With the right strap wrench (not the rubber type but the woven cloth type for delicate surfaces plumbing - i.e. chromed brass), managed to pull apart. Many were not glued but pressed together then lacquered.
My take - glue if you must, use appropriate Loctite or equivalent.
I believe Loctite has some tamper glues (visual disassembly).
What is the benefit of glue? Is it to make the light tamper proof, disposable, or some hidden benefit?
Some manufacturers have said that Warranty claims are significantly reduced with glued lights versus not glued.
If we can find a suitable glue that would stop the casual person while allowing us to open things with no damage and minimal effort I think I could have success in pitching that.
We would need to have an exact product / application in mind though to show them.
For the glue this is an issue of finding the right glue, purple loctight might work but I would want to see some reviews of someone experiencing this.
For a tamper evident seal on the bezel I really can’t think of anything that would not be visible on the outside of the light.
Thank you DavidEF. I suppose it is a benefit for the seller. Has anyone checked to see if sales for unglued lights are higher to offset the warranty claims? The answer to this might change the glue practice. Where is our math expert when you need one?
Well, you just need somebody to buy a tube of purple Loctite and test it on their lights. I don’t have the time, unfortunately.
Yeah, I figure someone has experience with it. Coming from cars I only ever used Blue and Red myself since that is what the local parts stores had.
From the Loctite web site, the purple (#222) dries to a rubbery texture versus the usual hard acrylique. Blue (#243), red (#263) and green (#290) are cyano acrylique esters (from my usage and some previous research).
Bezel can be tamper coded black (a thin glossy rim in joint) and when breaks leaves a whitish residue (hard to clean within the fine gap bezel / head).
Any examples of the bezel tamper?
I wounder if that rubber texture on the purple would be hard to remove on a flashlight with a lot of surface area for it to contact? I know they didn’t sell it locally in the past, I might need to check again when I am out to see if they have it now.
@ Texas_Ace:
I don’t have any examples of black bezel tamper. It was a suggestion but I’d think that Loctite would have such. Would have to make a request to their technical staff. But, any black lacquer would do the same. They do have some clear glues.