If you must cast the halves then why do you not dapp the cast
halves after you have cut off the sprues?
There are metal objects imbedded into the wax domes that
protrude beyond the surface ( used to support the object in the
investment when the wax has been burned out ) of the dome which
will be sanded off after casting the domes. It seems that a
combination of all the steps ( from the initial model to the
mold to the wax to the imbedding to the casting to the finishing
), but especially the filing off of the protrusion of the object,
adds up to the overall degradation of the finished product (not
to mention my lack of skill).
Also, at the point of insertion of the metal object, there must
be atleast a 2 mm thickness of the dome, plus another layer above
the object inside the dome to facilitate complete fillingof the
casting- hence the need for a thicker than usual dome.
Thanks for your help, Peter Slone