A lathe (10) or other rotating machine includes a chuck (14) for holding a work piece or tool. The chuck (14) is operated between grasping and releasing positions. A chuck guard (28) is mounted on a housing (12) of the rotating machine. The chuck guard (28) has a transparent window (32) and is mounted for pivoting movement between a position covering the chuck (14) and a position exposing the chuck (14). A chuck guard extension (41) with a window (40) is attached at a front lower end of the chuck guard (28).
