Shallowing a focus ring

I have a number of custom focus rings from good people on this forum, that I like to use to dress up my hand-held units, and/or make the units easier to handle.

However, makers of custom focus rings seem to often thread the rings to a generous depth. As a result, when the lens is fully seated in the focus ring, I find that with some lasers I cannot focus to infinity before the focus ring bottoms out on the heat sink. That is, with the lens fully seated in the focus ring, I can't get the lens close enough to the diode.

What do you experts suggest to "shallow out" a focus ring, so that the lens will firmly seat at a shallower depth, and so get closer to the diode before the ring bottoms out on the heat sink?

Extra credit for reversible techniques that do not permanently alter the focus ring.

You could place a small shim in the ring and prevent the lenstube screw to deep into the ring. Or you can glue it with superglue but that is more a permanent solution.

You need Non permanent thread lock.

This is what you do.

First Put some Plumbers tape around the lens Itself. Then Screw the lens in till Infinity But dont have the focusing adapter connected. You might have to turn the laser on and off to do this so you dont burn your fingers but you should be OK if you hold the lens correctly.

Make sure you put enough plumbers tap that its a Nice snug fit when you screw it in.

Once it is set to infinity put just dab of Non Permanent thread lock in the threads of the focusing adapter and quickly screw it on all the way till it is flush with the host.

Let it sit for 15 minutes to dry then unscrew the lens that is now attached to the focusing ring. Remove the Plumbers tap and you should be all set now.:wave:

Note:

You might want to go past infinity a tab So You can have a little play room when focusing.

^^ I think that is not the problem. The lensbarrel is too short and the focusring hits the sink before the focus is set on infinity. The threads in the focusring is too deep and "eats" too much of the barrel.

exactly you use teflon tape to make the threads tighter and you only thread it into the focus adapter as far as you want to. it will stay with enough Teflon tape

EDIT: lazeerer's way will work too, i find it easy just to use teflon tape

Blord said:

^^ I think that is not the problem. The lensbarrel is too short and the focusring hits the sink before the focus is set on infinity. The threads in the focusring is too deep and "eats" too much of the barrel.

Click to expand...

If you Screw the lens in first without the focusing ring deep enough to infinity then in that position put some thread lock on and screw the focusing adapter in as far s it can go then once the thread lock sets and hardens and he removes it, it will alway now be able to screw in far enough to focus and even better it will always be at infinity when screwed in all the way.

Try adding a rubber washer in between the focus ring and the lens nut. This should add 1-2mm of clearance and make the fit much tighter.

I misread it as 'swallowing a focus ring'.. which would have been far funnier to read

Thanks, folks.

Some good concepts here. I'm not much of an idea guy, but I'm good at taking suggested concepts and ideas and adapting them to solve problems. You've given me some really good ideas.