Balancer shafts are used for 4-cylinder engines for reducing vibrations.  Starting with a forged shaft that is suitably clamped, the required imbalance is generated by means of lengthening/centering.  The component is produced ready-for-assembly through a process of turning and subsequent induction heating/tempering, grinding and finishing.  The hard-machined surface is subject to particularly high demands on roundness, which is documented using Fourier analysis.  To achieve this, appropriate and reliable measuring devices are used.