Machining jig and machining method

A machining jig that holds a workpiece with respect to a tool that partially removes an outer peripheral surface of the workpiece, the machining jig comprising:

• a first jig including an inner peripheral surface having a shape similar to a contour of the workpiece and an outer peripheral surface including a first inclined section inclined with respect to an axial direction of the workpiece;
• a second jig including an inner peripheral surface including a second inclined section configured to be fitted to the first inclined section;
• a base to which the second jig is coaxially fixed;
• and
• a sliding mechanism that enables a large-diameter portion of the first inclined section and a small-diameter portion of the second inclined section to move toward and away from each other,
• wherein the sliding mechanism causes the small-diameter portion of the second inclined section to press the large-diameter portion of the first inclined section so that compressive stress is applied to the outer peripheral surface of the workpiece at a position to be removed by the tool, and
• wherein the sliding mechanism includes
• an internal thread portion formed continuously from the large-diameter portion of the second inclined section, and
• an external thread portion that is provided on the base and meshes with the internal thread portion.