sand paper! woah, there. it its a core shot, take it to a shop bc youll need a base weld. if not, just do the ptex thing and youll be fine. black ptex is better than clear, who really cares what your bases look like. who realy cares what the tops of your skis look like, either? so light the ptex stick on fire, let it drip into the hole, then press it in with a metal scraper (itll probably get really hot, so watch out). then use the scraper to very carefully remove the excess ptex, mind not to gouge out any more of your base.