>>9856462okay, so you're suggesting the inner skull remain where it is, teeth and all, and just essentially the cheeks, sides of the snout, and eye-area flip up.. I had a similar idea once.
there's a problem with that you haven't considered, and that goes beyond materials tolerances, the need for a thin shell on the head with tiny thin hinges.... see unless something has a completely flat edge where you're folding it, you're gonna have gaps.