  We present a mechanical laser shutter design that utilizes a DC electric
motor to rotate a blade which blocks and unblocks a light beam. The blade and
the main body of the shutter are modeled with computer aided design (CAD) and
are produced by 3D printing. Rubber flaps are used to limit the blade's range
of motion, reducing vibrations and preventing undesirable blade oscillations.
At its nominal operating voltage, the shutter achieves a switching speed of
(1.22 $\pm$ 0.02) m/s with 1 ms activation delay and 10 $\mu$s jitter in its
timing performance. The shutter design is simple, easy to replicate, and highly
reliable, showing no failure or degradation in performance over more than
$10^8$ cycles.
