An actuator having two parts which extend in a main plane and are mutually connected by three bridges. The method includes providing a plurality of wafers having a set of pilot wafers and a set of remaining wafers, polishing each of the pilot wafers according to an original process time, determining a compensation time for the pilot wafers, determining an update time by adding the compensation time to the original process time and polishing the set of remaining wafers according to the update time. The turbine system can have a blade assembly.