[Unanswered]  A custom Vanishing Moot issue

Um, hi all. A while back I tried to make a custom Vanishing Moot and figured out an approximate Parts combo of: Driger F's Attack Ring, an 8-Balance Weight Disk (it may supposed to be an 8-Heavy, looking back), a Magnacore (probably either Neo North or MW), and an SG Sharp blade base (from Galman).

The blade has been all made and it spins fine enough, but the thing won't stay until the launcher. Does anyone know a Part swap or life hack that could get this Cyber Elephanton custom working?