One of the problems with the commercial spinner nuts is the fact that the hole in them is too small to get anything into really get the spinner nut really tight enough to stay on. I got tired of that and now I make my own spinner nuts and I Make a hole in them so that a 1/4" shank phillips screw driver can be used to tighten them. This has solved my problem. See photo.

"NO" I do not recommend that loctite be used on a propellor shaft. Just my own personal opinion.

Good Luck

Lee