A binding machine includes a body, an actuator coupled with the body, and a punch mechanism housed in the body for punching a stack of sheets upon actuation of the actuator. The punch mechanism includes a plate including a plurality of punch pins. The punch pins are configured to punch through the stack of sheets during a punch stroke, the punch stroke defining a force profile. A portion of the force profile defined from a first drop in force to a last peak force before a final decrease has no more than a 15 percent change in force relative to a normalized maximum force of the force profile.