The traditional methods for cellulose pulp evaluation require a transformation into laboratory hand sheets in conjunction with drainability tests. In this evaluation, as a previous step, the pulp undergoes a treatment of the fibers by a laboratory refining procedure, which simulates the process made at paper mills. The PFI mill method is still the most used in laboratories, as it provides a uniform treatment of pulp giving more homogeneity in the refined fibers and uses a small quantity of sample. The PFI mill traditionally used in the Forest Projects Department of the Technological Laboratory of Uruguay (LATU) provides robustness and confidence along with control charts and historical data already well established. This confidence is based on inter and extra reference analysis. Recently, our laboratory has acquired a new PFI mill. The objective of this study was to achieve a similar beating effect of the new PFI mill as the effect of the one habitually used, in order to have interchangeable mills. The adjustments were made over the new mill by using mixtures of silicon carbide powder. To evaluate the beating effect a reference Eucalyptus pulp was refined. After each adjustment a refining was made and the Canadian Standard Freeness (CSF) measured. When the CSF reached the approximate desired value, hand sheets were made to determine the physical properties. Finally, when the results were comparable to those of the long-established mill, several refinings were made to evaluate their stability. The results proved that both mills were equivalent, thus concluding that the grinding procedure was successful allowing an optimized indistinct use of them.