To start Locktite is the perfect quick answer to this type of problem but there where days when Locktite was not available and there where other cures for this problem, some a little odd and others that can cause a sharp intake of breath. One of the best methods of re timing a screw I have ever found is some strands of coarse wire wool warped under the head and the screw is timed by removing or adding some strands. This works so well because the strands of wire wool act as a lock washer as well as adding depth keeping the screw in place. Adding Shellac to the screw thread and assembling acts like Locktite when it drys. Now for the sharp breath intake ones, place a piece of lead sheet on a hard surface next lay your screw on that next hit the screw lightly just enough to distort the thread on the hit side. In doing this the distorted threads will tighten the screw in the threaded hole it goes into. Last but not least Tin the thread with Solder this will increase the screw size and make the screw tight in the threaded hole. There are other methods like putting a length of copper wire in the hole before the screw. So Locktite really is an answer to a modern Engineers prayer's.
