An employee was operating the T-nut machine. She put a piece of stock in the machine and was going to install a T-nut into the end of the stock. She activated the machine for the T-nut installation, but the T-nut did not go into the stock properly. As she attempted to remove the T-nut from between the stock and the ram, her hand hit the limit switch. The ram then plunged forward, pinching her right middle finger between the ram and stock. Her fingertip was amputated. The guard was in place at the time.