AbstractFines are an important factor in the papermaking industry with respect to their influence on the mechanical properties of paper. A procedure offering the possibility to produce handsheets with a constant amount of fines, as well as the determination of the fines content, is of great importance in evaluating the influences of different types of fines. In this work, a method based on a white water circulation system and fiber morphology characterization using a flow cell was evaluated. Three different wires for handsheet forming were studied (120-mesh, 325-mesh, and 500-mesh), and the 325-mesh wire was chosen for further trials. Using the 325-mesh wire, a constant amount of fines was achieved after discarding seven handsheets. This method allows reliable evaluation of the effects of primary as well as secondary fines and a cellulosic additive on handsheet properties.