A grinder assembly which minimizes deviations in the path of ground material as well as other interfering structure is provided. A receiving chamber is disposed above a grinding mechanism and provides for direct transfer of material to be ground from the outlet aperture of the receiving chamber to the grinding mechanism. The grinding mechanism is driven from above and, therefore, no other structure necessary which may interfere with the ejection of grounds from the grinder assembly. A vacuum-stabilized base plate may also be provided in order to securely and removably mount the grinder assembly to a surface.