PSA: purple loctite exists, and you should use it.

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[ARCHIVED THREAD] - PSA: purple loctite exists, and you should use it. (Page 1 of 2)

Posted: 2/28/2019 2:27:17 PM EDT

You see threads constantly about loctite. Blue rules the day, mainly because it’s an automotive product that’s available everywhere. But for firearms, this magic goop can cause a lot of grief. And often does.

Loctite makes many threadlocking products. And you should consider purple for your firearm needs.

Amazon link

Now, don’t let the “low strength “ part fool you. It’s not low strength. It’s suitable for fasteners up to 1/4” . Let that sink in. Despite its widespread use, blue loctite is made for bolts. Using it on a 6/32” screw isn’t going to make it any better, it’s just going to make it harder on you. Remember, threads and torque do the locking. The threadlocker is only to prevent vibration from backing that out. Purple is beyond suitable for that task and won’t let you down.

Yes, even on a gas block. I’m not your threadlocking supervisor. Just trying to pass along a pro tip for folks that may not know it exists.

Experience: 8 years in the avionics industry. Working with small screws 6, 8, and 10/32. Sometimes even 4/40 and smaller. Often times brass or nonferrous materials. High strength threadlocker turns a 5 minute disassembly into a half day ordeal.

Use whatever you like. But me and my perfect screw heads are happy with purple.

There’s also a green , used for penetrating already tightened threads. Useful in a scenerio where something has to be precision tightened before being locked. It’s very VERY thin and also works great.

TL;DR

Op thinks he knows better than y’all. Here’s some tits for your attention.

Fixed: I guess ol Veronica will have to do.

Posted: 2/28/2019 2:29:50 PM EDT

[#1]

OP makes informative post, then delivers.

Posted: 2/28/2019 2:30:32 PM EDT

[#2]

I like blue.

Thanks for the tits though.

Posted: 2/28/2019 2:31:04 PM EDT

[#3]

Great post. I have some purple that I always end up passing over for blue. I need to stop.

Posted: 2/28/2019 2:31:47 PM EDT

[#4]

Thanks for all that and in before the lock I'd assume

Posted: 2/28/2019 2:31:50 PM EDT

[#5]

Agreed, pox be upon those that use red to secure fine firearm screws.

Posted: 2/28/2019 2:32:37 PM EDT

[#6]

FPNI and IBTL (probably)

Posted: 2/28/2019 2:33:20 PM EDT

[#7]

I like Vibra-Tite VC3 better because you can reuse it several times. I still use the purple from time to time. Thanks for the Gif.

Posted: 2/28/2019 2:33:35 PM EDT

[#8]

Just mix red and blue.

Posted: 2/28/2019 2:33:35 PM EDT

[#9]

Purple is preferred for tiny screws like you will see on scope rings and bases.

Posted: 2/28/2019 2:33:44 PM EDT

[#10]

Yep, OP speaks truth, but if you really hate someone - use green.

Fine set of hangers there, and IBTL.

Posted: 2/28/2019 2:34:22 PM EDT

[#11]

I have and run blue because that's what I know. I've never had trouble getting it off. But then again, I also used red for a scope mount once, and somehow that came off just fine as well.

Neither have given me trouble backing out or coming loose, so I don't expect purple will either. Once my little tube of blue runs out, I'll go with that instead. Thanks OP!

Posted: 2/28/2019 2:34:26 PM EDT

[#12]

Nice tits!

Posted: 2/28/2019 2:36:12 PM EDT

[#13]

Is purple readily available? Frankly I rarely go into AutoZone or other auto parts stores and tend to get my locking compounds, sealants, lubes and spray chemicals at Walmart since they are the same only cheaper. I will have to check Walmart for the purple drank loctite.

I have not had a problem with blue loctite on firearms usage, so far. Use it on an AR pistol gas block locking screws (with the barrel dimpled), handguard locking screws and the RMR and plate screws on my Glock 19 Gen5 MOS with zero problems so far. Proper screw torque is key and if those are correct, locking compound is just a fail safe.

Posted: 2/28/2019 2:36:44 PM EDT

[#14]

This thread started out good then became awesome. Thanks for the info and the gif.

Posted: 2/28/2019 2:36:57 PM EDT

[#15]

I've been using red.

Posted: 2/28/2019 2:38:46 PM EDT

[#16]

I've never had a problem with blue Loctite on anything gun related. Red and green are a PITA, but blue is just right, IMO.

Posted: 2/28/2019 2:39:50 PM EDT

[#17]

That’s how you make a thread!

Informative and boobs. All Threads should start like this.

Posted: 2/28/2019 2:40:06 PM EDT

[#18]

Quote History

Quoted:
I've been using red.

View Quote View All Quotes

View All Quotes

Quote History

Quoted:
I've been using red.

Quoted:
Agreed, pox be upon those that use red to secure fine firearm screws.

Used red on an ADM mount and Haley Strategic thorntail mount. Came off just fine for me...

But I use blue now.

Posted: 2/28/2019 2:40:28 PM EDT

[#19]

OP delivers twice in one thread!

Posted: 2/28/2019 2:41:52 PM EDT

[#20]

In before the Loctite

Posted: 2/28/2019 2:41:54 PM EDT

[#21]

Purple is my favorite

Posted: 2/28/2019 2:45:59 PM EDT

[#22]

Quote History

Quoted:
I like Vibra-Tite VC3 better because you can reuse it several times. I still use the purple from time to time. Thanks for the Gif.

View Quote

JB weld for the win.

But seriously I agree with this poster. Also primary arms and others are starting to include a sample pack with some optics.

Posted: 2/28/2019 2:46:49 PM EDT

[#23]

Quote History

Quoted:
OP makes informative post, then delivers.

View Quote

FPNI

Posted: 2/28/2019 2:48:12 PM EDT

[#24]

Henkel (owner's of Loctite) makes a lot of stuff. The color is a quick indicator of what you are generally using, but need to pull the specs for the details. There are multiple blue and red formulations.

As far as loosening bolts that are threadlocked, a little heat is your friend. Pretty sure almost all of the readily available formulas go back to liquid form before you hit 300 deg, high temp variants approach 500 deg

EDIT: For those of you seeing different results, technically there is proper procedure for using Loctite products. Clean, oil free parts is a prerequisite. If you want the full effect in some circumstances you also need to prime the parts. Most people I know do not have the primer in their shop.

http://dm.henkel-dam.com/is/content/henkel/threadlocker-user-guide%20

Posted: 2/28/2019 2:48:34 PM EDT

[#25]

I like pink titlocker on tits. Works good on tits.

Posted: 2/28/2019 2:50:04 PM EDT

[#26]

Quote History

Quoted:
Is purple readily available? Frankly I rarely go into AutoZone or other auto parts stores and tend to get my locking compounds, sealants, lubes and spray chemicals at Walmart since they are the same only cheaper. I will have to check Walmart for the purple drank loctite.

I have not had a problem with blue loctite on firearms usage, so far. Use it on an AR pistol gas block locking screws (with the barrel dimpled), handguard locking screws and the RMR and plate screws on my Glock 19 Gen5 MOS with zero problems so far. Proper screw torque is key and if those are correct, locking compound is just a fail safe.

View Quote

Most likely not at the local store. But one tube will last for many years. In aviation, vibrations is an actual hazard. We use safety wire, tab locks, locknuts, all kinds of crap.

But when blue enters the fray. That’s when shot starts getting damaged. And the RV guys were the worst. Home built aircraft that has blue or red on every hardware store potmetal screw in the instrument panel. They sheared plum off at worst, most rounded out .

Think of every nice revolver you’ve seen with jacked up screws because someone didn’t k ow that fine blade drivers exist.

Blue works just fine, until it doesn’t. Just thought I’d share is all.

Posted: 2/28/2019 2:50:05 PM EDT

[#27]

I celebrate the entire collection.

Posted: 2/28/2019 2:50:15 PM EDT

[#28]

Quote History

Quoted:
I have and run blue because that's what I know. I've never had trouble getting it off. But then again, I also used red for a scope mount once, and somehow that came off just fine as well.

Neither have given me trouble backing out or coming loose, so I don't expect purple will either. Once my little tube of blue runs out, I'll go with that instead. Thanks OP!

View Quote

Don't run threadlocker. It means you put on too much.

Just use some.

Posted: 2/28/2019 2:51:13 PM EDT

[#29]

Great post OP. Never knew the purple existed. Thanks for the info and dem’ beams !

Posted: 2/28/2019 2:52:26 PM EDT

[#30]

Blue is my go to, Red if I will die if the bolts fail....

Posted: 2/28/2019 2:57:09 PM EDT

[#31]

The actual break strength a given threadlocker will have is a function of the size of the fastener.

The rated "you'll need heat or power tools to remove this" for most red threadlockers or "it will take a good wrench" for most blue threadlockers is based on it being applied to fairly large bolts, usually 1/2", 3/4" or even 1" depending on the spec.

Since most common knife or firearm fasteners are quite small, the threadlocker will have far less area to adhere to, and thus will break much easier than the rating implies.

For many small (1/16" or smaller) firearm fasteners, I find blue loctite 242 is rarely strong enough, and red 271 is easily broken with hand tools.

I have used purple loctite before, mostly on very large fasteners where blue or red would be stronger than desired. But large fasteners are actually pretty rare on modern firearms, and most of them do not require threadlocker at all.

Now if you want loctite that will destroy firearms: Green wicking threadlocker.

Posted: 2/28/2019 2:57:25 PM EDT

[#32]

Can’t find it anywhere near here, had to order from amazon.

Even the industrial supply shops around here looked at me like I was crazy when I asked for some for my 6 second mount.

Posted: 2/28/2019 3:00:53 PM EDT

[#33]

Way ahead of you brother, but thanks for spreading the gospel.

For about three years now I purple loctite all scope mount and ring screws, plus action screws on my rough use hunting rifles. It has never come loose until I wanted it to, and never locked things together either.

ETA: Degrease everything first, I use acetone.

Posted: 2/28/2019 3:02:37 PM EDT

[#34]

Purple is ok for flats and button heads smaller than 6-32. I have had no issues removing fasteners with blue and have used it for decades.

The production company I used to work for, used blue on almost everything.

Anything on my vehicles or my Harley gets red.

I have never had purple in my house.

Try some Loctite 620 if you want some funzies.

Posted: 2/28/2019 3:08:17 PM EDT

[#35]

Blue has never given me issues. I use the purple stuff for tiny screws like scope ring cap screws and the like, though.

Posted: 2/28/2019 3:12:57 PM EDT

[#36]

I just ordered a bottle, thanks. I was using 242/243 and vibratite on stuff.

Posted: 2/28/2019 3:15:55 PM EDT

[#37]

Posted: 2/28/2019 3:17:32 PM EDT

[#38]

Quote History

Quoted:

Don't run threadlocker. It means you put on too much.

Just use some.

View Quote

Can I at least walk it?

Posted: 2/28/2019 3:18:58 PM EDT

[#39]

Quote History

Quoted:
Henkel (owner's of Loctite) makes a lot of stuff. The color is a quick indicator of what you are generally using, but need to pull the specs for the details. There are multiple blue and red formulations.

As far as loosening bolts that are threadlocked, a little heat is your friend. Pretty sure almost all of the readily available formulas go back to liquid form before you hit 300 deg, high temp variants approach 500 deg

EDIT: For those of you seeing different results, technically there is proper procedure for using Loctite products. Clean, oil free parts is a prerequisite. If you want the full effect in some circumstances you also need to prime the parts. Most people I know do not have the primer in their shop.

http://dm.henkel-dam.com/is/content/henkel/threadlocker-user-guide%20

View Quote

The parts being clean is much more important than whether you use blue or purple, on another note for SS hardware primer should be used most of the time.

Posted: 2/28/2019 3:22:41 PM EDT

[#40]

Quote History

Quoted:
Just mix red and blue.

View Quote

This is what I came to post.

Posted: 2/28/2019 3:27:39 PM EDT

[#41]

I like vibratite. I've gotten a RMR stuck to a mount with loctite before and it isn't fun. Luckily Trijicon bailed me out and let me send it in to them.

Posted: 2/28/2019 3:28:02 PM EDT

[#42]

Don't sleep on green loctite. Especially if it is something preassembled and you just want to add some additional protection from loosening without cracking the fastener loose. It is added after the fastener is torqued. I became aware when White Oak sent it to lock set screws on a match upper.

Posted: 2/28/2019 3:29:26 PM EDT

[#43]

Quoted:

There’s also a green , used for penetrating already tightened threads. Useful in a scenerio where something has to be precision tightened before being locked. It’s very VERY thin and also works great.
https://i.postimg.cc/s2CKmfc6/A8-C00-AE5-C304-4-A34-880-D-5-A71260698-C6.gif

View Quote

OP is referring to Green 290 "Wicking Grade", not Green 620 Retaining Compound. Green 620 is usually used in slip-fit applications, not on threaded fasteners.

Tony

Posted: 2/28/2019 3:39:34 PM EDT

[#44]

Thank you - one more bottle of loctite to leak-out/dry-out/lose.

Posted: 2/28/2019 3:44:32 PM EDT

[#45]

Wow, and here I have been doing it wrong for 30 years, good thing I checked arfcom GD.

That blue stuff is especially sneaky the way it's worked fine all 87,000 times i've used it...yeppers, like a snake inna grass waiting for the right moment to spring into action.