Edge alignment device

The device (3) has a setting tool (2) fastened on a freely rotatable bearing hub by a fastening unit (6) in a press fit. The fastening unit comprises a fixing head with three fixing elements, which is brought in operative connection with the bearing hub such that the fixing elements press the tool in the press fit. The fixing elements are arranged radially to a rotation middle point of the tool. The fixing elements comprise point bearing surface that stays in fastening condition at the tool.