IAMKAOS

i have question. has any one had any problems with engine vibration using the somewhat newer master air screw nylon g/f 3 series props. i have always used the the older nylon m.a. props for years with no problems. our local hobby shop's no longer carry the older one's and just sell the g/f3's so recently i started using these and i believe they are too flexible. while flying my gp venus .40 i could hear vibration. i landed and found the screws that hold the cowling had come out. while flying my suhkoi 29 the exact same happened!!. these models had many flights on them with the older props with no problem. i used one of these g/f 3 props on my sig somethin extra and it sounded like it was going to blow apart in the air. last sunday i was flying my old sig four star .40 with a norvel .40 engine on it and it is one of the most smooth running engines i have ever owned. i installed a g/f3 prop on it and and the harmonic's from vibration was causing glicthes. i removed the prop and installed a old apc i had and the problem went away. i had one of my buddies check the balance of a couple of these g/f 3's using a prop balancer and they balanced fairly well. without question i believe these these g/f 3 series just flex too much causing harmonic vibration in the airframe of the model while in flight.