Post by supercopter on Feb 7, 2012 15:23:31 GMT -4
here is some info
The different grades work differently in some respects. Yes, the stuff is anerobic, however you might wonder why it does not harden in the bottles. According to some of what I have read, the bottle material is special in that it "breathes to prevent hardening. When trapped in the threads between a screw and a nut, the reduced access to air brings about the "hardening"
A point about the mechanical functioning of the thread locker is that it fills the space in the threads. As you may know when you want something to slide, it is harder to get it started than to keep it moving. When a threaded fastener is loaded sideways, the nut or head can slip on the surface it contacts and the threads can slip sideways as well because of the slight clearance between the the male and female threads. Once the surface is slipping it is not all that particular about which way it goes (same reason a car sliding on ice goes all over the place). If the thread is slipping, the easiest direction to go is "downhill" which in this case happens to be tangential motion in the threads, or "unscrewing". If the initial lateral slip is stopped then the "downhill" sliding between the theads (unscrewing) does not get a chance to loosen the bolt.
When reviewing the performance specifications, an interesting point to note is that "red" 271 and some of the other High strength versions show a peculiar characteristic. The breakaway torque for the removal strength "blue" 242 loctite is higher than the "prevailing" torque to keep it moving once it breaks away (as you would expect). BUT for some of the high strength loctites the prevailing torque is higher. That is to say soon after it breaks loose and starts moving, it jams up tighter than ever. Apparantly the crumbs roll up in little lumps that jam up the threads even more.
The different grades work differently in some respects. Yes, the stuff is anerobic, however you might wonder why it does not harden in the bottles. According to some of what I have read, the bottle material is special in that it "breathes to prevent hardening. When trapped in the threads between a screw and a nut, the reduced access to air brings about the "hardening"
A point about the mechanical functioning of the thread locker is that it fills the space in the threads. As you may know when you want something to slide, it is harder to get it started than to keep it moving. When a threaded fastener is loaded sideways, the nut or head can slip on the surface it contacts and the threads can slip sideways as well because of the slight clearance between the the male and female threads. Once the surface is slipping it is not all that particular about which way it goes (same reason a car sliding on ice goes all over the place). If the thread is slipping, the easiest direction to go is "downhill" which in this case happens to be tangential motion in the threads, or "unscrewing". If the initial lateral slip is stopped then the "downhill" sliding between the theads (unscrewing) does not get a chance to loosen the bolt.
When reviewing the performance specifications, an interesting point to note is that "red" 271 and some of the other High strength versions show a peculiar characteristic. The breakaway torque for the removal strength "blue" 242 loctite is higher than the "prevailing" torque to keep it moving once it breaks away (as you would expect). BUT for some of the high strength loctites the prevailing torque is higher. That is to say soon after it breaks loose and starts moving, it jams up tighter than ever. Apparantly the crumbs roll up in little lumps that jam up the threads even more.