A dual arbor chopper that is configured such that the knife blades of the chopper do not require shims after being sharpened. The arbors utilize a blade attachment recess that is oriented in an opposite direction as existing arbors used in choppers, in combination with a clamping block to provide support against the cutting force against the blade. An attachment fastener is provided to attach the clamping block and the knife blade to the arbor through an aperture provided in the clamping block and the knife blade. The cutting edge is positioned in the same location in the new and sharpened condition, thus eliminating the need for shims.