You need a pair of good strap wrenches, a miniature gas torch and a lot of patience.
When you heat up the bezel, stop heating when the temperature reaches 160 °C, which will soften even the stonger loctite. Above that temperature, the aluminium reflectors will delaminate, and the electronic parts will deteriorate, especially capacitors.
At 180 °C, the o-rings will start melting, and the dome of any LED inside will pop.
I use a K type termocouple probe for temperature measuring. I'm planning to buy an IR thermometer for opening lights.
If the bezel contains a plastic reflector, or a plastic coated reflector (like the Fenixes) please stop at 100 C. Many CPFers boils the bezel in a plastic bag to be sure not go above 100 °C. It doesn't always work, since 100 °C is not enough to softens all four type of loctite.
For about 10 minutes, keep the bezel at 160 °C, still providing some heat. The loctite requires some time at high temperature before it softens.
While the bezel is still hot, engage it in the strap wrenches. It will open.
While my description can sound simple, handling a hot bezel is not. Wearing mittens can be an idea; also protective goggles, since glass windows may shatter. Alignment of strap wrenches is essential, and another person helping out can be useful.
Consider that nat HAIII will get slightly clearer after such operation.
Also, if you try to open Fenixes, you need some extra practice since the walls are tiny, there is very little grip, and their loctite is the "definitive" one, and is not color coded as "our" loctite; in addition, the reflectors are made of polyester coated aluminium. The coating is very temperature sensitive.
Consider that some combinations of finer threads and excess of loctite (or epoxy) may render a light unopenable; a typical examble being the Arc4.
In my experience, 70% of the openings have been successful. The other 30% is in my "horror box" - the most expensive collection of garbage I ever produced.
Hope this helps
Anthony
