In ASTM C109, Standard Test Method for Compressive Strength of Hydraulic Cement Mortars using 2-in (50mm) Cube Specimens, the specimens are prepared using a mechanical mixer equipped with paddle and mixing bowl to prepare a mortar of cement, water and standard sand. Flow is determined using a flow table and cubes are compacted into two layers, cured and immersed in lime water until tested. The usual test age of the cubes are 3 days, 7 days and 28 days.