On Loctite

[ferider]

I’ve (dis)assembled > 100 folders over the last two years, and in the process adjusted how I work with thread lockers. Proper use is important as I don’t want to keep readjusting my knives. Also, as I have watched Youtube videos and other user’s comments, I felt a dedicated thread would be in order. I hope this is the right place. Otherwise, moderators, feel free to move, of course.

There are many different types of thread-lockers, plenty of Chinese and Korean fakes, etc. Today, I only use the real stuff, in particular

• Purple Loctite (222)
• Blue Loctite (242)
• And Red Loctite (262)

And I can recommend them.

Here is what I do with them:

• Use purple/blue/red depending on the screw size. For example, purple is more than plenty for T6 or similar small screws (e.g., clip screws).

• Use different color depending on the screw type. For example, a Hinderer small (scale) allen screw will strip much easier than a small Spyderco T6 torx screw from Colorado or Japan (Spyderco Taiwan and China screws appear much softer).

• Whatever color I use, a loose screw – even after being “thread locked” - will remain _much_ looser than a thread locked tight screw.

• To disassemble (in particular for red), you need localized heat greater than 550° F. I don’t really like to use a soldering iron as it’s hard to keep a screw unmarked, and difficult to get high temperature quickly. Easier to use a gas flame, when I can avoid to burn a scale, etc. LT is quite heat resistant; for example, this is for 262:

• Keep the screws clean. When assembling a folder there is oil, it gets pulled easily into pivots, fingers get greasy, etc. Don’t touch screws with your hands, use tweezers instead. Sometimes an acetone (nail polish) cleaning is required, etc.

• Once LT is applied, I give myself about 10’ max. for manipulation/tuning of a knife. In particular red LT dries up quickly, and if I mess around – say with a Pivot action – too long, thread locker will be worthless.

• And finally the most important part: let LT dry at least 24 hours without touching the knife. These days I use 48 hours, typically. As an example, here are 242 curing times, for different materials:

You can see that, e.g., for stainless screws in a stainless pivot or standoff, after 24 hours, 242 barely reaches 25% of its full strength (admittedly, an M10 Pivot screw is quite large - but you get the point ...). If you are impatient, you can accelerate curing with heat (e.g., put it over night close to your heater or similar), like this:

Thanks for reading,

Roland.

PS: charts are from the manufacturer (www.loctiteproducts.com)

 

[eveled]

I use One that’s different you put it on the threads let it dry then assemble. It is adjustable without loosing its locking ability It works through many assembly cycles. Vibratite vc3
https://www.vibra-tite.com/threadlo...threadmate/?cookie-state-change=1573258267110

 

[Wowbagger]

Fascinating !
Just when I was going to change threads . . . (ah I know all this stuff / I use loctite at work) . . . you whipped out the slow cure on stainless card.
Why would you say this is ?
Thanks for posting this.

Generally I would have to say people over do the grade of loctite, blue and red on undersize fasteners, but they don't clean the surfaces / treads well or at all so their results can be all over the map.

PS : and as a side note I have even had excellent results with natural bee's wax on small fasteners 56 TPI where even thread locker designed for the purpose has proved too tenacious and failed me at least seventy to a hundred times ! ! ! !

I use natural bee's wax on adjusters that are under tensile tension and the "approved" locker has seized up so bad the fastener twists off and breaks in two. This is on stainless male thread with aluminum female thread. Exposed to out side winter elements for years including salt from the streets.
Natural bee's wax locks (maybe partly because of having some sugar still in the wax) yet has not seized.

 

[ferider]

Fascinating !
Just when I was going to change threads . . . (ah I know all this stuff / I use loctite at work) . . . you whipped out the slow cure on stainless card.
Why would you say this is ?
Thanks for posting this.

Generally I would have to say people over do the grade of loctite, blue and red on undersize fasteners, but they don't clean the surfaces / treads well or at all so their results can be all over the map.

PS : and as a side note I have even had excellent results with natural bee's wax on small fasteners 56 TPI where even thread locker designed for the purpose has proved too tenacious and failed me at least seventy to a hundred times ! ! ! !

I use natural bee's wax on adjusters that are under tensile tension and the "approved" locker has seized up so bad the fastener twists off and breaks in two. This is on stainless male thread with aluminum female thread. Exposed to out side winter elements for years including salt from the streets.
Natural bee's wax locks (maybe partly because of having some sugar still in the wax) yet has not seized.

Engineer here but not a chemist. It has to do with chemical reactivity, I think. From the web:

"... there is a maximum gap that anaerobic adhesives will cure through. Controlling that gap is critical to achieving full anaerobic curing. The speed of the cure is related, not only to the gap, but also the reactivity of metals being used. For example brass is more reactive than steel which is more reactive than anodized aluminum." (I assume they mean stainless)

Very interesting on the bee's wax, thanks !