Bought new prop for new boat and need help PLEASE!

[RCaddict0]

OK...If you guy's read my other thread I just boght a new Thunder Tiger Outlaw JR OBL and when I got it I noticed it had a plastic prop. From what I read metal props are much better. So I called Hobbieco and asked if there was a direct replacement for this boat. They gave me this part number AQUB9725
http://www.gravesrc.com/AQUACRAFT_GrimRacer_42x55_Copper_Beryllium_Titaniu _p/aqub9725.htm
Its the same prop but metal ofcourse. The prob. is when I go to install it the teeth on the shaft are a bit to small to make a secure fit ito the prop. I hope this makes sense so far. Then the next issue is that the shafts not quite long enough with it to tighten the lock nut down all the way. Is there a new shaft I can buy that will work. Thanks

[iamandrew]

so do you mean that when the prop is installed onto the drive shaft, you can still turn the prop a tiny bit, like 1 or 2 mm rotated?
If so you just got the same problem i had the other day, its a 3/16 prop on a 4mm drive dog. had to change to 3.16 drive dog :(

[RCaddict0]

Thanks! That sounds about right. Like the inlets in the prop are bigger than the "drive dog" Im guessing you call it. This reminds me of learning RC from the start again. I remember starting in the hobby. I was lost. I feel very confident in my cars and trucks now. But moving into boats and planes. What about the drive shaft? Its a solid shaft. Do I just measure it and look for one in the same diameter but a few mm longer?