• There has been a recent cluster of spammers accessing BARFer accounts and posting spam. To safeguard your account, please consider changing your password. It would be even better to take the additional step of enabling 2 Factor Authentication (2FA) on your BARF account. Read more here.

Threadlocker best practices

M

mrzuzzo

New member
Joined
Dec 9, 2013
Location
Los Gatos Hills
Moto(s)
The one outside of Starbucks
Name
Victor
Need some threadlocker guru help here...

This past weekend I mounted my cases for a short trip down the coast to my bike and when I got to my destination, one of the bolts was very loose. I did use blue threadlocker, but I think it wasn't used correctly in this case.

1 - Torque. This is a M8x25mm, 12.9 grade fastener that is holding my pannier frame to the bike. Manual doesn't specify a torque value but based off the internet, generic torque value for such a bolt is roughly 32 Lb-ft. Does the torque need to be lower with threadlocker? Why?

2 - Amount of threadlock. I used a small drop on the end of the bolt... Maybe I should have used more of it?

3 - Cleanliness of bolts/thread. The bolt and thread had some old threadlock residue on it from previous use. It's nearly impossible to clean all of it off. Not sure if this affected my installation.

4 - Contamination of threadlock. I've read that if the bottle of threadlock touches metal, the liquid inside contaminates and is not really usable any more. How true is this? How do you tell if it's still usable?

Thanks!
 
Not a guru by any stretch, not really a mechanic besides my own bikes anymore either, but since I seem to be the queen of random stuff managing to rattle loose/break/fall off, I tend to be, um, very "generous" with my blue thread lock - like a fairly generous stripe down the length of the bolt. Haven't had trouble getting things back off (well, maybe a little trouble, but they eventually came out), and at least they're not randomly falling out when I do it that way. :laughing

Also, a quick line with a sharpie/paint marker can make it very easy to see if bolts are starting to turn out at all without you needing to dig out any tools. Easy way for a quick visual at stops, especially if there's something new you've attached.
 
Last edited:
1. 32 sounds good for that grade.
2. Don't put it on the end, run it up the side in the threads. If you use too much it will just squeeze out, but a drop isn't that much on that size bolt.
3. Dirt and grease kill threadlock.
4. Metal catalyzes the stuff. However the rest of that statement is not true. Al that will happen is that if you get enough ionization from metal contact it will set up. It takes a fair amount of contact and time.
 
afm199 said:
1. 32 sounds good for that grade.
2. Don't put it on the end, run it up the side in the threads. If you use too much it will just squeeze out, but a drop isn't that much on that size bolt.
3. Dirt and grease kill threadlock.
4. Metal catalyzes the stuff. However the rest of that statement is not true. Al that will happen is that if you get enough ionization from metal contact it will set up. It takes a fair amount of contact and time.
Click to expand...

+1. I did a ton of research on thread lock/torquing as my company produces and sells wheel studs for race cars.

Bolt and hole threads need to be as clean as possible. Use a wire brush and brake cleaner to clean the bolt threads. Use a thread chaser and brake cleaner to clean the female threads. Dirt/grime/buildup on the male/female threads could lead to false torque readings.

Edit: Also, how long did the thread locker cure before taking off? Diavel sounds like a vibey bike. For best results, it needs 24hr to cure.
 
Last edited:
Honey Badger said:
Not a guru by any stretch, not really a mechanic besides my own bikes anymore either, but since I seem to be the queen of random stuff managing to rattle loose/break/fall off, I tend to be, um, very "generous" with my blue thread lock - like a fairly generous stripe down the length of the bolt. Haven't had trouble getting things back off (well, maybe a little trouble, but they eventually came out), and at least they're not randomly falling out when I do it that way. :laughing

Also, a quick line with a sharpie/paint marker can make it very easy to see if bolts are starting to turn out at all without you needing to dig out any tools. Easy way for a quick visual at stops, especially if there's something new you've attached.
Click to expand...

I use this to mark all critical bolts so I know if they start to loosen just by looking at it:

http://www.amazon.com/Tamper-Proof-...er red bolt&qid=1461689164&ref_=sr_1_3&sr=8-3
 
afm199 said:
1. 32 sounds good for that grade.
2. Don't put it on the end, run it up the side in the threads. If you use too much it will just squeeze out, but a drop isn't that much on that size bolt.
3. Dirt and grease kill threadlock.
4. Metal catalyzes the stuff. However the rest of that statement is not true. Al that will happen is that if you get enough ionization from metal contact it will set up. It takes a fair amount of contact and time.
Click to expand...

Thanks for the tips, I'll use brake cleaner to clean the bolts before inserting.

I've heard that using less torque is better with threadlocker, like 20% less. That higher torque is actually worse for threadlocker. Is this true?
 
mrzuzzo said:
Thanks for the tips, I'll use brake cleaner to clean the bolts before inserting.

I've heard that using less torque is better with threadlocker, like 20% less. That higher torque is actually worse for threadlocker. Is this true?
Click to expand...

I've never heard that and don't understand it. Any source? All the threadlocker does is turn to plastic in the open spaces of the thread/bolt interface and make it harder to turn.
 
Only reason I would think to reduce torque with thread locker would be for same reason to change torque with anti seize, it will allow the bolt to turn easier and you can get more torque on the bolt than with dry threads.
 
afm199 said:
I've never heard that and don't understand it. Any source? All the threadlocker does is turn to plastic in the open spaces of the thread/bolt interface and make it harder to turn.
Click to expand...

Apparently Loctite recommends 20% less torque

wet vs dry torque values, see the linked article

that said, i'm pretty bad with non-critical torque values. i go by feel unless it's over 50 ft/lbs :wow
 
Right, basically anything that acts as a lubricant reduces friction. I'd still torque as normal though.

It's an anaerobic, so keep that in mind relative to fastener size. If they're larger, you may want to try a gap filling type.

And if blue isn't cutting it, don't be afraid to try red, just start with very little and see how it goes. Use even less on smaller socket head fasteners.
 
Hold the Blue threadlocker up right, shake vigorously. Once you have reached sufficient shakage, throw it in the trash can. Red loctite. 1 drop (maaaybe 2 on the chubby guy).
 
afm199 said:
1. 32 sounds good for that grade.
2. Don't put it on the end, run it up the side in the threads. If you use too much it will just squeeze out, but a drop isn't that much on that size bolt.
3. Dirt and grease kill threadlock.
4. Metal catalyzes the stuff. However the rest of that statement is not true. Al that will happen is that if you get enough ionization from metal contact it will set up. It takes a fair amount of contact and time.
Click to expand...

:thumbup
 
Blankpage said:
I could use something like that at work to tell if someone tampered with my reference points. If it was an exposed bolt wouldn't any impact remove a glob of that stuff?
Click to expand...

They are not permanent, if that was what you were asking. It's only served as a marker that breaks when a bolt or nut is loosen, so you could spot it easily.
 
afm199 said:
I've never heard that and don't understand it. Any source? All the threadlocker does is turn to plastic in the open spaces of the thread/bolt interface and make it harder to turn.
Click to expand...
I think that comes from a wet vs. dry bolt. And I agree that loctite is not the same as a greased bolt. Torque it just like a clean/dry bolt. Full torque specification.
 
You must log in or register to reply here.
Back
Top