Circular mat cutting apparatus

An apparatus for cutting circular arcs or holes in a picture mat comprising:

• a flat base upon which the mat rests;
• a platform provided above said base;
• and
• a cutting means for cutting the mat including
• a disc member,
• a disc mounting means for mounting said disc member for rotation adjacent said platform about a center axis,
• a disc locking means for releasably locking said disc member against rotation about the center axis,
• a crank mechanism having an axle extending perpendicularly through said disc member and a mounting arm attached to and extending perpendicular from a bottom end of said axle below said disc member,
• a crank mounting means for slidably mounting and releasably locking said crank mechanism to said disc member at a selected one of a plurality of positions along a radial path through the center axis,
• a cutting blade,
• a blade mounting means for adjustably mounting said cutting blade along said mounting arm and at a cutting angle to the mat;
• whereby the circle or arc is cut in the mat by rotation of said crank mechanism, at a location determined by the position of said crank mounting means and said disc mounting means, and with a diameter determined by the position of said blade mounting means.