Abstract: Apparatus that is particularly suited for machining hard dense ceramic materials comprises a vertical milling machine within an enclosure. The machine has a plurality of slides for moving a spindle holding an end mill in the x, y, and z directions. The x and y slides are located above the elevation of the work table and any workpiece held thereon. Air flows downwardly from the region of the x and y slides and through gaps associated with two fabric shields which have horizontal portions that translate respectively in the x axis and y axis directions. The shields inhibit coolant that contains work piece particulates from traveling upwardly toward the x and y slides. A tool changer system comprises a tool holding tray (30) mounted adjacent the work table within a housing having a movable cover. The housing enables the tool tray to be removed from the enclosure through an access door while the machine tool is operating and coolant is flowing.