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Need help with lens "binding" in module

hazerkitten

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Hi guys,

I have a new 465nm build I completed and it's gotta be my favorite so far! I've had it maybe a week and I am now starting to get some binding in the lens when I go to adjust the focus. The diode is open can so I don't want to do anything inside the module.. is there anything I can apply to the threads on the lens to lube it up? It's starting to grab pretty good, to the point where my adjustment knob starts to come off.

Parts came from DTR: the lens is their G8 and its inside their copper module

Thanks for the help!!
 



RA_pierce

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Best thing to do is to avoid adjusting focus a lot. Copper is very soft and, since we don't apply lubricants to the inside of the module (for good reason), it's easy for the friction between the module and brass lens nut to cause galling. The friction may also cause little bits of metal to flake off of either component which can jam up the threads. First, I'd use a small paintbrush to clear out any dust or metal chips. If the threads aren't too rough, you can apply a little teflon tape to the lens nut which will tighten the threads a bit but will reduce the metal-on-metal friction.

Unfortunately, the only real remedy for seized threads is to run a tap through the them, which can't be done with the diode installed. If you apply lubricant, there is a good chance that you'll end up with some on the diode or lens, or it will make its way into the beam path and will burn.

If the threads are really badly worn...
You can try removing the lens nut completely, checking the threads on both the module and lens nut, and use a sharp needle file or pick to clean up the threads. It's easy to make it worse, however, so I don't recommend this last option unless you're confident you know what you're doing.
The nickel plated brass modules are better at resisting wear on the threads, in my experience, but of course the thermal conductivity is not as good as copper.
 
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hazerkitten

Member
Joined
Mar 20, 2013
Messages
126
Points
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Best thing to do is to avoid adjusting focus a lot. Copper is very soft and, since we don't apply lubricants to the inside of the module (for good reason), it's easy for the friction between the module and brass lens nut to cause galling. The friction may also cause little bits of metal to flake off of either component which can jam up the threads. First, I'd use a small paintbrush to clear out any dust or metal chips. If the threads aren't too rough, you can apply a little teflon tape to the lens nut which will tighten the threads a bit but will reduce the metal-on-metal friction.

Unfortunately, the only real remedy for seized threads is to run a tap through the them, which can't be done with the diode installed. If you apply lubricant, there is a good chance that you'll end up with some on the diode or lens, or it will make its way into the beam path and will burn.

If the threads are really badly worn...
You can try removing the lens nut completely, checking the threads on both the module and lens nut, and use a sharp needle file or pick to clean up the threads. It's easy to make it worse, however, so I don't recommend this last option unless you're confident you know what you're doing.
The nickel plated brass modules are better at resisting wear on the threads, in my experience, but of course the thermal conductivity is not as good as copper.
Makes sense. The only thing that gets me is that it's less than a week old! I hate removing the lens since it's open can but I took it out and cleaned the threads up, lots of compressed air, etc. For now it seems back to normal
 

RA_pierce

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Makes sense. The only thing that gets me is that it's less than a week old! I hate removing the lens since it's open can but I took it out and cleaned the threads up, lots of compressed air, etc. For now it seems back to normal
Are you using the spring in the module?
I've found that sometimes they will scratch the surface of the copper and/or brass lens nut and produce small metal chips.
There are ways to prevent this but I usually just omit the spring altogether.
 

hazerkitten

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Mar 20, 2013
Messages
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Points
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Are you using the spring in the module?
I've found that sometimes they will scratch the surface of the copper and/or brass lens nut and produce small metal chips.
There are ways to prevent this but I usually just omit the spring altogether.
Yeah, I’m using the internal spring coupled with the external spring from SL
 




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