Thread Lock Question

[xrunner]

What I have been searching for is the older type of thread lock that you may have seen used before. You know where they put a small dollop of red "stuff" on the end of a bolt's threads where the nut is. The "stuff" is very hard and keeps the thread locked while in addition will show tampering.

What I can only find now (and I've searched my ass off) is the newer type of loctite stuff which goes on the threads before assembly (it comes in different colors for different needs) but you can't see it after assembly.

Does anyone know where to get the older style? I say older style because I may be searching for it using the wrong terminology, and it may still be used a lot.

Any help would be appreciated.

[GK]

You are probably thinking about "tamper-proof" lacquer. RS components, Farnell and others sell it. As far as I can gather it is just red nail polish with a different bottle label an a price premium. Get your missus to pick up half a dozen bottles of the latter at the two dollar store the next time she goes out shopping instead. Or just buy it yourself if you're comfortable walking into a store and buying girly stuff.

 

[xrunner]

You are probably thinking about "tamper-proof" lacquer.

Aha - yea I bet that's what I need to search for. Many thanks! 

[GK]

I know that RS Comp. sell it, as I have several RS-branded bottles of it at work. However I've used several different search terms and I can't immediately find it on their website with their garbage parametric search engine.

 

[LabSpokane]

It's called torque seal. It's a bit fussy to use, but here you go:

http://www.aircraftspruce.com/catalog/cspages/f900.php

[Richard Crowley]

The stuff you paint on the surface AFTER screwing it together is NOT "thread lock"
The only way to LOCK threads is to use something BETWEEN the threads.
This is typically "Loctite" or a similar product.

Loctite is generally made in two major varieties.
The red-color Loctite is for permanent locking. It takes a HUGE amount of torque to break it.
The blue-color Loctite is for semi-permanent locking. It can usually be un-screwed without breaking the screw.

Nothing you can paint over the top after the fact will "lock" the threads.
This has become a popular misconception is recent years.
People see the ordinary lacquer painted over screws and mistake it for "thread lock".
For example, the stuff referenced by LabSpokane is described by the manufacturer as: “Anti-Sabotage Lacquer”.

[Psi]

People should have a damn good reason before using red loctite, that stuff is evil.

[GK]

Actually, the thick nail-polish-like stuff (marketed as tamper proof/evident, etc) works quite well a "locking" small machine screw nuts. I've been using it for years on M3 mounting hardware for circuit boards subjected to such vibration that T0-92 packages are already heavy enough to tear their solder pads from the PCB (if the pad diameters are anything less than 80 thou) and have never had a nut come loose, even after 10+years of service. After tightening the nut you just apply a little dollop to the top of it and coat the protruding thread. The nut won't work its way back up a coated thread and can be a surprisingly difficult to undo, especially when some prick has walked off with your miniature nut driver set again and all you have to grapple the nut is a pair of long-nose pliers.

I use Loctite Threadlocker Red 271 ("permanent") for my flywheel fastening bolts. Works a charm but is still undone easy enough with a decent sized breaker bar. The next strength down is green, but in any case if it ever is a problem all you have to do is apply sufficient heat and the red just gives way for disassembly. Not that evil, really.

[GK]

Here is the stuff I use at work! A waste of time attempting to find it with the RS site search engine but Google got it on the first displayed link 

http://uk.rs-online.com/web/p/epoxy-coatings/1965245/




I swear the stuff is just re-labeled nail varnish. It even smells exactly the same.
 

[SeanB]

Exactly, I bought a few bottles at a clearance sale of assorted colours, reds, greens and yellows, along with clear. You can use the clear to hold screws into the front panel, putting it between the countersink and the screw, and afterwards using a small swab to wipe it into the screw head to fill it, leaving it smooth on the panel. If you are putting on a panel overlay use any colour close to the overlay, with the filled screw head preventing a indentation showing up in the panel finish.

It will eventually dry even if it is in a screw thread, so if you want a truly evil use place a drop on the thread close to the base then tighten the nut down so it spreads out at the bottom.Removing the nut will in most cases result in a broken screw, unless it is a high tensile version. Those will never come off, though if clamping tension is lost they will rattle until they wear either a big enough hole to fall off or wear out the shaft till it breaks.

[Stonent]

I just always assumed they used women's nail polish.

[LabSpokane]

For example, the stuff referenced by LabSpokane is described by the manufacturer as: “Anti-Sabotage Lacquer”.

I know exactly what it is, and isn't. I was trying to show what torque seal was.

Loctite is not an anti tamper seal, nor is the converse true. Two separate substances. Two distinct jobs.

[GK]

It appears that Loctite does make an equivalent product:

http://au.element14.com/loctite/1705056/varnistop-loctite-7400-uk-version/dp/3072034?ost=tamper+evident+paint&categoryId=800000000394

Though at a retarded $209 for a 20mL bottle it appears yet another product to have been vetted by E14's shit-for-brains-price-determination-robot. Might pay to source it from elsewhere or just cop the indignity of buying women's nail varnish. You could always bring one of your electronics projects along to the cosmetics store to demonstrate to the salesperson that your intended application is an entirely manly one. They probably wouldn't just assume that you're some kind of weirdo then.
 

[SeanB]

Dollar store or local China mall sells it as well, and a lot cheaper. As you are not using it on your body do you really care if it contains lead, bismuth or any other toxic material as either a colour or an ingredient. Just buy a case of assorted colours and no one will care.

[zapta]

I am using Vibra Tite VC3 (the package in the middle) because it's reusable. Probably not what the OP is looking for though.

http://amzn.com/B008D6GHY6

[Someone]

Loctite is generally made in two major varieties.
The red-color Loctite is for permanent locking. It takes a HUGE amount of torque to break it.
The blue-color Loctite is for semi-permanent locking. It can usually be un-screwed without breaking the screw.

Its a little more complicated than that, the colour guides only apply to their thread locker range:
http://www.henkelna.com/industrial/Loctite-Threadlockers-by-Color-14023.htm

Workshops I've been in always called the 222 low strength "Red" for instance, and you can get the 609 "Green" which is great for permanent bonds in metal. 90% of thread locking jobs, 243 universal "Blue"

[VK5RC]

I've used Loctite 222 on the top of M3 nuts to provide a little more rattle proof protection for some of my home brew gear (microwave transverters), that gets transported by car a bit, and I wouldn't appreciate a nut floating around. I have found the 222 does penetrate a few turns down and is undo-able but not too annoying.

[Yago]

Not exactly the topic, but might be of note.
Some threadlock has antigalling properties, can be very handy when constructing from different metals (steel/alloy/titanium).
If it galls, you'll struggle to disassemble for service.

[GK]

Just buy a case of assorted colours and no one will care.

Besides the stock at work, I could probably make use of the stuff in the home workshop too. Though I am a bachelor at the moment. I could perhaps ring up my mummy as ask her to get me some vivid red nail polish the next time she goes out shopping. I hope that wouldn't be misinterpreted. I already hate the fact that the local supermarket routinely shifts their stock around and I am often forced to search for my linen soap (real men use nothing fancier - I even "shampoo" my hair with it) amongst the shelves of tampons and other assorted girly stuff. That just isn't right.

[G7PSK]

Touch up paint pens work very well for locking threads while showing evidence of tamper, I used to use car touch up paint of the bottle and brush variety for locking IF can slugs,worked very well. Whatever you do don't use the yellow loctite used to be called bearing fit, it never comes undone unless heated to high temperature, I have seen 50mm shafts wring off with the stuff.

[xrunner]

Thanks for all the replies! I think I can find something now. I just couldn't think of what to call it other than "thread lock" and I kept getting the same results no matter what other phrases I tried. I just wanted to tell Google - can't you figure out what I really mean!

[SeanB]

Touch up paint pens work very well for locking threads while showing evidence of tamper, I used to use car touch up paint of the bottle and brush variety for locking IF can slugs,worked very well. Whatever you do don't use the yellow loctite used to be called bearing fit, it never comes undone unless heated to high temperature, I have seen 50mm shafts wring off with the stuff.

Loctite 603, used to hold bearings in place inside an oil bath. Removal is normally fatal to the bearing. I used some to hold in keyways, and they never rattled, even with a less than perfect fit. Held some gears onto a shaft as well, in addition to the section of tin can used to get the 2mm too large clearance between gear and shaft down to interference fit. Last I heard it is still running. Needed it working NOW.

[djacobow]

Did anyone else see "thread lock" and assume the post was about concurrent processes?

Learn to use a mutex, dude.   j/k

[miguelvp]

Did anyone else see "thread lock" and assume the post was about concurrent processes?

Learn to use a mutex, dude.   j/k

Not really, but my first instinct was to suggest talking about politics, religion, and similar to get the thread locked

but I didn't want to say it since it would be off topic, but since you broke the seal I couldn't help myself.

[Yago]

Did anyone else see "thread lock" and assume the post was about concurrent processes?

Learn to use a mutex, dude.   j/k

Not really, but my first instinct was to suggest talking about politics, religion, and similar to get the thread locked

but I didn't want to say it since it would be off topic, but since you broke the seal I couldn't help myself.

Ooo Miguel, painful punnage!
I approve!