Is there an amount of maintenance to do to a practice philly to ensure it keeps doing it's job? I've used it since March of this year. I need to "sand" a couple of nicks out on the smooth side and would also like to know the best way to take them out. I rolled the blade just before a full stop (rookie mistake) and sliced in a little ways. Thankfully the blade continued to shave well. I just would like to know if there is anything I need to do to either side.