Curve cutting method and apparatus

A fixture for use with a power driven cutting tool for cutting a circle of predetermined radius in a workpiece, the fixture comprising, in combination:

• a base including means for fixedly mounting the base with respect to the power driven cutting tool, the base including a pair of guide ways,
• a pivot arm for supporting the workpiece for presentation to the cutting tool,
• a first slide engageable in one of the base ways and carrying a pivot arm pivot point for engagement with a fixed end of the pivot arm,
• a second slide engageable in the other base way and carrying stop means engageable with the pivoted non-fixed end of the pivot arm for establishing a working position of the pivot arm, and
• the relative positions of the first, second and pivot arm slides being adjustable to allow the pivot arm and workpiece to be rotated to the working position while the cutting tool engages the workpiece in a nonbinding fashion to bring the cutting tool into the working position for cutting a circle of the predetermined radius from the workpiece.

A method of cutting a defined curve in a workpiece, the curve having at least one defined axis, the method comprising the steps of:

• providing a supporting base having a fixed relationship with respect to a cutting tool,
• supporting a workpiece on a pivot arm mounted on the base at a first pivot point such that the pivot arm with workpiece is pivotable toward the cutting tool,
• mounting a workpiece on the pivot arm at a second pivot point such that the workpiece is rotatable about the second pivot point,
• engaging the workpiece with the cutting tool by pivoting the pivot arm toward a working position in which the cutting tool engages the workpiece,
• rotating the workpiece about the second pivot point while pivoting the pivot arm toward the cutting tool to an extent sufficient to prevent binding of the cutting tool, and
• rotating the workpiece about the second pivot point with the pivot arm in the working position to cause the cutting tool to cut the defined curve.