I have a cheap plastic board with an in-built pull-through sharpener, metal and ceramic. I have have trouble believing that this can be any decent, but I have tried it on a bad knife. The knife is now noticably sharper. Does that mean this is actually good? Or will a good sharpener make it even sharper? Or is this a bad sharpener and will long-term damage my blade?
Which of those is true, and how can I tell if that sharpener is good or if I need a real one?
Best Answer
All sharpeners remove steel. When sharpening a knife, you ideally want to remove as little steel as possible to get a very specific angle on the blade edge.
If you were getting a blade sharpened professionally, they would typically go through different grits to get it smoother and smoother and eventually a polished edge. For a home pull through sharpener, you're using a single grit that will do most of the work. Ideally it would be something in the middle that will maybe take a little longer to remove nicks in your blade & grind the edge down, but not pull off too much steel.
There are two dangers with a cheap sharpener, that I can think of:
Hard to say what is exactly happening in your case. That all said, if it's a cheap blade and your knife is sharper, then use it maybe? Without knowing what it was, I don't know that I'd gamble with a good blade. "Cheap plastic board with a in-built sharpener" is probably a clue that it's cheap though.