Knives are among the first tools used by mankind. The most primitive ones were made of wood, and later from rock broken and shaped to produce sharp edges. The discoveries of bronze, iron and steel has allowed the creation of knife blades that are sharp and strong. Knives have many uses: as tools, utensils, hunting implements as well as for self defense. Knifes are still used and valued today as when the first ones were created. While modern knives have strong blades, they can still get dull. When this happens, you can sharpen it yourself. One method is with a belt sander. It is effective and cheaper than expensive sharpening machines. While a vertical belt sander is available at most hardware and building supply stores, adapting it for knife sharpening takes a little but of work.
Cut a piece of angle iron with a hack saw so that it is 1-1/2 inches wide and four inches long.
Make two rounded slots centered on either end of the iron. The slots should be 1 inch long. Make a second, shorter slot next to one of the 1 inch slots.
Bend the angle iron into a 90 degree angle so that one side is 2-1/2 inches long and the other 1-1/2 inches. One of the slots will bend with the angle of the iron.
Smooth the interior of the slots with a file.
Put the tool rest in the vise so that the half of the angle that has the two slots touch the side of the vise. Bend the edge down on the half that has only one slot cut into it.
Fasten the tool rest to the belt sander so that the end with one slot extends across the belt of the sander.
Determine the angle of the rest by using a protractor. The tool rest will help hold the knife in place for sharpening.