I like to use these little portable sharpeners. I find they work best to keep a good edge on a knife, but they're to much work if you're trying to put a new edge on a completely dull knife. So don't wait to use one when the knife is dull, instead keep it handy and use it often while using your knife to keep the edge up. They weigh next to nothing in a pocket or backpack and the Gerber Diamond model shown is only $2.99 from MidwayUSA.com.

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