Use a small 3-cornered file or a jeweler's file to deepen the splines a little. The splines should slide together almost all the way with no more than a firm push. Tightening the nut will lock them together tight enough to require a puller to separate them again.
Jerry

"It is better to be silent and be thought a fool than to speak and eliminate all doubt!" - Abraham Lincoln
Cringe and wail in fear, Eloi- - - - -we Morlocks are on the hunt!
There is nothing noble in being superior to your fellow man; true nobility is being superior to your former self. - Ernest Hemingway
Love your enemies and drive 'em nuts!