How to Sharpen Cutting Tools

Clean the knife's blade to get rid of any dirt or rust caked onto it. If the dirt and rust don't come off easily with soapy water and light scrubbing, use a stiff brush to remove remaining debris. Protect your hands and fingers while doing this so they don't get cut.

Choose a sharpening tool that fits your sharpening needs and skill level. A whetstone, also known as a sharpening stone, will most likely be the best choice. These stones are simple to use and come in a number of different grades. Whetstones can be used by just about anyone to sharpen cutting tools, especially those that have little to no experience doing so. A file can be used as a preliminary sharpening tool before you move onto a finer grain, or it can be used on cutting tools like garden shears that have large blades and don't necessarily have to be razor sharp or have a precise blade. Power sanders get the job done quickly on just about any type of blade, but should only be used by professionals or individuals with a lot of blade sharpening experience. The power sander creates a lot of friction between the sharpening surface and the knife, and the heat from that friction can permanently damage the blade if you're not careful.

Apply water or oil to the knife or the sharpening implement you use. The friction generated from the sharpening causes heat, which the water or oil helps to reduce. If the metal of the blade gets too hot, the heat may take the temper out of it. If you use a power sander, wet the blade at least every few seconds. If you use a non-moving surface to sharpen the blade like a whetstone, you can coat it in oil or water instead of continually dipping the blade in it.

Move the blade along the sharpening service in long, slow, even strokes. Begin with a coarser surface and once the blade is smooth, move to a surface with a finer grain. If you find the blade has a nick in it, smooth it out with a file before moving on to a finer surface. For every 10 or so strokes to the outer, main edge of the blade, put one stroke on the minor or inner edge of it.

Hold the blade up to the light and look to see if light reflects off the edge. Keep sharpening the blade until you see no reflection.

Test how well the blade cuts. If the blade makes clean cuts, then it's adequately sharpened. However, if it catches or makes snags, you'll need to continue sharpening it until it doesn't.