After a month or so of testing an idea, I may have found a possible solution that may help some.
If you have a twisty that you like to pocket-carry, that either comes on or unscrews itself into separate parts, try slipping a thick little automotive o-ring onto the head so it sits in the gap between head and body. Screw up to it quite snugly and you’ll find the two parts of the light will stay in place without tightening up or loosening. I have an Astrolux 01 and a L10 that I like to pocket-carry but always had problems with - the Astrolux used to regularly unscrew itself and the L10 always used to come on. Neither do either any longer.
The solution may look quite ugly, but it really isn’t that that bad and it provides a nice tactile separation between head and body for me. In addition, it means I can lubricate the threads so the twisting mechanism is very smooth, but still have a secure way of carrying the lights. I simply pull the o-ring slightly up the body before twisting to activate the light - it’s a very natural action.
(a piece of advice - make sure the o-ring is quite thick. If it is too small it will get pinched and not slide out the way like a thick one happily does
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