The present disclosure is directed to a machine for making green sand molds by an impact mechanism which imparts an impact from an impact head driven by the explosive force of suddenly released compressed air in such a way that the molding head strikes the sand and imparts its kinetic energy by way of an impulse to the sand, thereby packing the sand around the patterns. It has been discovered that by using the impulse principle in molding, the sand is uniformly packed and uniform mold hardness results.
