Abstract: The invention comprises a portable apparatus for the manufacture of bowstrings that facilitates application of bowstring serving cord when producing new custom built archery bowstrings, particularly for compound bows. The invention provides a power driveable device for rotating and advancing a serving tool utilizing a winder head that is pivotable and stowable to allow use of a bowstring jig without interference from the winder power head when not needed and then pivoting the power head into a drive position when serving is to be wound around the bowstring. The power serving winder also provides for serving from both ends of a bowstring without remounting the string on a jig apparatus, and for applying tension to the bowstring while being manufactured.