Spend enough time working in a machine shop and you're bound to pay a visit to the emergency room for a cut finger. First comes the sting as the ER physician injects you with a local anesthetic, then the tug of the thread as she drags the suturing needle, a type of surgical needle, through your skin. This traumatic experience is painful enough, but without the sharp edge imparted to those needles through special machines known as needle-point grinders, those sutures would feel as if the doc were using a darning needle from grandma's sewing kit.
