Core Mold of Puppet Jaw: Core molds consist of an outer mold for the 'outside' of the cast piece, and an inner core mold for the 'inside' of the cast piece. This will produce a hollow casting. You can control precisely what the inside of the casting will look like, which you can not do with rotocasting. Core molds are used a lot in the toy making industry. In the pictures above, there is the core mold put together, then apart, and then photos of the outside and inside of the cast piece as produced by the above core mold.