I had the same problem with my ss shruiken prop. some blades were loose then one blade fell out and the tip broke I was so bummed was able to repair it then I used silver grey duck tape cut into small pieces enough to fold over the end of the blade that goes inside the round piece so its not...
Nice collecton N3M3SIS!!
However seeing that somewhat heavy Predator bust on one of those thin detolf shelves so high up makes my heart race...worried for you!!!!
If my memory serves me correct I ve seen two pretty recent on ebay both buy it nows the most recent for $600 and the other ridicously overpriced for $1200
cheers