Wire electrical discharge machine and wire electrical discharge machining method

A wire electrical discharge machining method for using a wire electrical discharge machine that includes:

• a mounting table having a placement plane on which a workpiece can be placed;
• a first guide portion and second guide portion that support and stretch a wire electrode therebetween, wherein the workpiece is subjected to electrical discharge machining under a condition where the relative position between the first guide portion and the second guide portion is adjusted so as to align the inclination of the wire electrode with the tilt of the workpiece with respect to the placement plane;
• and,
• a probe configured to be movable integrally with the first guide portion and detect abutment against the workpiece placed on the mounting table,
• the wire electrical discharge machining method comprising:
• when a three-axis coordinate system is defined by an XY-plane corresponding to the placement plane and a normal direction of the placement plane,
• a storing step of storing as an offset the relative position in the XY-plane between the first guide portion and the probe that is in a detected position of abutment against the workpiece before changing the relative position between the first guide portion and the second guide portion;
• a tilt information acquiring step of acquiring tilt information representing a tilt state of the workpiece with respect to the placement plane;
• and,
• a correcting step of correcting the stored offset based on the acquired tilt information and thereby obtaining an offset corresponding to the tilt state of the workpiece after the relative position between the first guide portion and the second guide portion is changed.