Fineness of division of a original hummer mill is controlled mainly by the size of hole in the screen, but screen wear out very rapidly. On this test, modified hummer mill is used which doesn’t have screen. Fineness of division is controlled by the size of adjustable delivery hole of grinded grain and number of hummer plate. The grinding performance of the modified machine is much less then the screen type machine, but modified machine dosn’t have wearing parts and also the machine is for practical use of very fine size of grinding.