Hi I have changed both of mine and not used anything to close them and never come open in use, if thats ant help, Only my personal experience though.
regards john.
The tiny screw (on a fixed, non-flipping) key is usually threadlocked in place. A brief warm with a soldering iron is enough to soften the threadlock to the point where the screw can be undone without obliterating the head. Once it has been undone a time or two it doesn't need to be heated again, but nor does the threadlock need to be replaced.