Villa- I doubt the blue loctite would give you a problem with spinning the crank after breaking the nut loose, but as several others have stated it's simply not needed. A prop nut with enough torque on it will stay put without any glue or not-glue as the case may be. Loctite is a great product for the things it's needed for like holding helicopters together and keeping mufflers on, but cranks have fine enough threads that if you get the 20 ft lbs or so that you really need to clamp the prop down right that nut isn't going to move.