A method and apparatus for processing workpieces to form parts. Tools associated with a multi-spindle machine may be positioned with respect to a plurality of workpieces on a fixture comprising a plurality of platforms and an adjustment system. Each platform may be individually moveable with respect to others in the plurality of platforms about a number of axes. The plurality of platforms may be configured to hold the plurality of workpieces in which each platform may be configured to hold a workpiece in the plurality of workpieces during operations performed by the multi-spindle machine. The adjustment system may be configured to move each of the plurality of platforms about the number of axes independently from the others in the plurality of platforms. The operations may be performed on the plurality of workpieces using the multi-spindle machine and the fixture to form a plurality of parts.