Bend the outer leg of a paperclip at a 90-degree angle using your fingers.
Bend 1/8 inch of the tip of the extended leg of the paper clip 90 degrees downward using a pair of needle-nose pliers.
Bend 1/4 inch of the extended leg 90 degrees to the right of the other bend using a pair of needle-nose pliers. This creates a makeshift tension wrench.
Bend the outer leg of the second of the paperclip at a 180-degree angle using your fingers.
Bend 1/8 inch of the tip of the extended leg 45 degrees upward using a pair of needle-nose pliers. This creates a makeshift feeler pick.
Insert the tip of the tension wrench into the bottom portion of the Sentry safe lock.
Insert the tip of a feeler pick into the top portion of the Sentry safe lock. Press up on each of the pins within the lock, starting with the one farthest back. Press up on each pin until you hear it "click" into place; this signifies that the pin has reached the sheer line. There are typically four or five pins that you must release to open the lock, all at various depths within the lock. Use the feeler pick to "feel" each pin as you unlock it.
Apply clockwise pressure on the tension wrench while moving each of the pins with the feeler pick. The lock will turn once each pin is in the "unlock" position.