Red Dots and Blue Loctite

I was changing out the battery in my Trijicon RMRcc (G43X MOS) and noticed that some of the Loctite had gelled and formed a band at the top of the screws.
I tried cleaning off the screws as best as I could, applied some Blue Loctite, and reinstalled them,
Hopefully it will hold.
I was wondering… how many here replace the screws every time they reinstall their red dot sight?

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Fingernail polish remover?

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I’ve never replaced them on mine, but I use a Trijicon on my Walther and have had the screws loosen a bit after about 2500 rds or so. I unscrew them, reapply the blue, and they stay put for the next 2-4k rds. I am not using a cut slide, though, but I am using the plate that fits in and replaces the rear site, so I think it might be taking a bit of extra vibe per rd. I just keep an eye on it.

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The blue loctite is doing what it should. The blue just gives a little extra adhesion to prevent them backing out under vibration (aka recoil). If it was all gummed up at the top, maybe the last application used a little too much or only applied it to the top.

Every time you “break the seal” of the loctite you should clean off the old stuff and reapply. Plain rubbing alcohol works usually, but if not nail polish remover like @PossumSlayer1 mentioned will do the trick. You need to clean it well because you need the loctite to adhere to both metal surfaces. If its dirty, then its adhering to old loctite or dirt/grease/etc and it will back out on you sooner than later.

Not sure about the RMRc, but the original RMR I believe you have to remove in order to change the battery. So every time you swap the battery, when you put it back together clean the screws and put on fresh loctite. IIRC that battery lasts 1-2 years?

I dont do it often, but if i need to remove a light or optic I will remove all the old loctite and put on a fresh coating.

Don’t forget to clean the threads of the screw hole as well as the screw itself. Small qtips work well for this.

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Thanks everyone!
I might go ahead and order new screws and clean the threads on the plates.

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Acetone cleans old Loctite. Pour some in a shot glass, drop the screws in, soak for awhile, then clean threads with a clean toothbrush.

Add a drop or two into screw holes and do the same. I use compressed air to blow out the holes, add a drop or two of alcohol and swab it with a corner of a cotton cloth, a shot of compressed air (again) and let it dry well - an hour should be more than enough since alcohol evaporates quickly.

Loctite screw threads only and your good to go.

The main thing is to get as much of the old Loctite out and clean the threads a best you can and let everything dry out.

PS: Acetone evaporates quickly too but if there’s grunge left in the threads it’ll still be there when the acetone evaporates. Canned compressed air will blow it all out.

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^^^ Good set of detailed instructions right there

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I don’t replace screws unless they are damaged or will not torque. I do put witness marks (aka index marks, torque stripes, registry marks) each time I re-install, however. Also, any residue on the threads will negatively impact getting the correct torque on the screws.

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I use Vibratite on my screws which allows reinstalling a couple times without reapplying.

Ive been using holosun red dots which also prevents me from having to remove the optic for a new battery, love that feature. After a couple reinstalls on my trijicon rmr pistols i just get new screws and use new Vibratite.

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