There will be times when you are out in the wilderness with a dull bushcraft ﻿knif﻿e and don’t have a sharpener with you. There are five common items you can use to sharpen a knife without a whetstone or blade sharpener.

One: The car window.

If you have access to a vehicle, the window makes an excellent sharpener. The top edge of every vehicle window is uncoated. Simply place the blade against the uncoated window edge, tilt the cutting edge of the blade to match the angle of the window edge. Once you have the cutting edge of the knife positioned against the window edge, press firmly and make three full passes along the entire edge of the knife blade. Flip over the knife and make three more passes in the opposite direction. Make sure the cutting edge of the blade faces forward for each pass.

Two: A ceramic mug.

Most undersides of ceramic mugs have an unglazed edge or ring. Place the mug upside-down on a flat stable surface. Once the unglazed edge is exposed, using the same technique as the vehicle window, draw the cutting edge of the blade across the unfinished edge. The thin ring of unglazed ceramic will sharpen the knife blade.

Three: An emery board.

The nail file has many uses besides filing fingernails. The emery board makes a perfect improvised blade sharpener. Place the emery board on a flat stable surface and draw the knife blade along the emery plane. Use the same technique as the prior examples to achieve excellent results.

Four: Another knife.

Another technique is using one knife to sharpen the dullest of your set. Take one knife and position it so the back of the knife is accessible. Then run the dull blade of the other knife along the spine, or back of the first knife. Draw the cutting edge across the back of the knife, and repeat the process on both sides until you have achieved a clean workable edge.

Five: A river stone.

If you are near a water source, you can use a river rock the same as a whetstone. Local the smoothest stone with a flat surface. Utilizing the basic sharpening technique as perfected in the previous examples, use the river rock the same way as a sharpening stone. You will attain a nice sharp edge.

Finally, once you’ve got your best knife edge honed to the sharpness needed, you can clean up your blade with strapping. Either use a standard leather belt or the nylon straps on any backpack. Both will work equally well. Easily pull the strap taunt and make smooth fluid passes with the blade edge pressed against the strapping. This will remove excess burrs and provide a clean and ultra sharp edge.

Try one of these techniques the next time you need to sharpen a knife without a sharpener. You will be surprised by just how great of an edge you can get.​