Abstract: A method for machining a sand molding element, comprising: inserting at least one hollow center body having an internal cavity in a predetermined position in a casting flask; filling the internal cavity of the hollow center body with unbonded sand; filling the casting flask with bonded sand to obtain a sand block; machining a mold cavity in the sand block; and emptying the internal cavity from the unbounded sand. There is also provided a method for machining a molding core from a sand block, comprising: providing a core base member having a concave upper surface; forming a sand block on the core base member with a lower surface of the sand block resting on the concave upper surface; and machining the molding core into the sand block, the molding core having a convex lower surface complementary to the concave upper surface of the core base member.

Abstract: A method for machining a sand molding element, comprising: inserting at least one hollow center body having an internal cavity in a predetermined position in a casting flask; filling the internal cavity of the hollow center body with unbonded sand; filling the casting flask with bonded sand to obtain a sand block; machining a mold cavity in the sand block; and emptying the internal cavity from the unbounded sand. There is also provided a method for machining a molding core from a sand block, comprising: providing a core base member having a concave upper surface; forming a sand block on the core base member with a lower surface of the sand block resting on the concave upper surface; and machining the molding core into the sand block, the molding core having a convex lower surface complementary to the concave upper surface of the core base member.