I'm not using a plastic or spun aluminum spinner on my engines but rather a spinner prop nut.The one that I'm currently using on my Homelite 30 is a Dubro #731 which is threaded for 5/16"x 24.I did away with the standard prop bolt and went with a 5/16"x 24 grade 5 stud and spinner nut set up instead.I used red Loctite on the stud where it threads into the prop hub and blue for a little extra security and peace of mind where the spinner nut threads onto the prop stud.Probably isn't necessary to use the blue on the spinner nut as it is quite snug after you've tightened it down (and is yet to loosen off while starting with the cordless) but I like to play as safe as possible especially when amongst other fellow flyers.Yeah.....I'm a bit of a worry wort when it comes to stuff like that.