Teflon tape is only used when the "Swiss Screw" machine that makes the optics mounts, is poorly set up. Its very easy to ensure good product yields if you back off the tolerances and make a loose fitting thread, The customer may then be damned to use the cheap junk. The quick, unprofessional trick is to then stuff the resulting needless gap with tef tape.
!
Laser show projectors are generally not stable enough to expect to be able to permanetly lock down anything but the required "Danger Laser" sticker. Dichro mounts drift, collimated laser diodes can shift emission locations, thermal cycling loosens things up, all sorts of reasons. So most of us would never use any chemical except on a very worn out optics mount.
!
Most good mounts use an 80 pitch thread, and the thread to thread distance is very small, and the threads are a few hundreds of microns tall at best. Epoxy will strip them when removed.
!
Steve
Qui habet Christos, habet Vitam!
I should have rented the space under my name for advertising.
When I still could have...