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We know a blunt knife is more dangerous than a sharp one, but how do you really know when your trusty 8-inch tool needs a tune-up? Here are three simple tests:

1. The onion dice. You shouldn't be crying your eyes out when chopping . If you are, your knife needs honing, since a less sharp blade crushes an onion instead of cutting it, which releases more gas into the air and makes you weep more.

2. The tomato slice. The knife should be able to cut a ripe tomato with almost no downward pressure. If the skin doesn't puncture, the blade is dull.

3. The paper cut. A razor-sharp knife will slash a piece of paper with a clean cut. If the paper winds up torn, with ragged edges, the blade isn't up to snuff.

Keep reading for suggestions on how to use a knife sharpening steel.