Rheology and viscosity data of liquid metals in high temperatures are important in metallurgical manufacturing processes. In this paper, a simple and low cost viscometer which can be used to measure viscosity of liquid metals and semisolid slurries in different shear rates is introduced. In this apparatus, the principles of the falling ball viscometer are used while accumulated with a counterbalance mass for decreasing ball speed and controlling shear rates. The accuracy of the instrument is demonstrated by using liquids with known rheology. The obtained data were comparable with the available results in the literature. (C) 2012 The Society of Rheology. [http://dx.doi.org/10.1122/1.4709431]