Towards the end of last ice season, I was attempting an ascent of Glass Menagerie, a Grade 4 ice route at Roadside Gully near Lock Haven, PA. Halfway through the steep curtain, I struggled to thread an ice screw into the ice. My screws, having endured 5 seasons of climbing, were fully dulled. Why I hadn't sharpened them beforehand or even in an earlier season is beyond me and inexcusable. At that moment however, I was just tired, scared, and fumbling to get a dull ice screw in to protect myself from a long fall. I managed to sink a screw, finish the route, and promised to sharpen the damn things before the next trip.
My real reservations in starting the process is that to sharpen ice screws yourself, you need to take a metal file to a $60 object that is responsible to keeping you alive and well. With a dozen screws to tune, I could destroy $720 of gear or bust my ankles, back or neck. Rather than let that bother me, I watched Black Diamond's handy video on sharpening screws. I bought some new files and built a wooden jig to hold the screws.
After working on the first one with some hesitation I succeeded in not destroying it. The following 11 went fairly easily after that. Now all that remains is for the weather to get cold and stay there... that and I need to do about 600 more pullups.