Received a Mora which was sharp, but not that sharp. Seeing as it's dark and cold outside, I thought I'd have a go at sharpening it. I now have bald patches from both moras I own. The three penknives I have in my possession however just won't get that sharp. I almost have trouble cutting paper with them without tearing it. Any ideas? Plus I definitely need to replace one of the blades on my Mauser... Any ideas how expensive that is?