Scrape the goo off with a razor blade. Save it, as it's almost pure THC (scissors hash). Then wipe them down or soak them in isopropyl (rubbing) alcohol or vegetable oil. I usually take them apart and clean them at the end of a trim job. There's just one screw to take out, and the spring comes off and goes back on easily. Once they're squeaky clean, give them a light coating of oil to keep them from rusting, and you're all set.