Instant Improver

How to sharpen a knife on a rock

Spanners and hammers might disagree, but in our opinion the knife is the king of tools. A man’s knife can help him prepare and eat lunch in the wild, make a shelter and even clean his fingernails, because ash, carcass and soil-packed cuticles are never a good look. It can, however, do none of the above if blunt. Cue Andrew Thorpe of the Scout Association ( with advice on how to give yourself a cutting edge…

“Hunt out a porous rock, such as a fine sandstone,” says Thorpe. “Rocks located next to rivers often make good stones as they have been smoothed by the water and will often be of a manageable size. Wet the stone and place it on a flat surface.”

“Hold the knife in your right hand and lay one side of the blade flat on the stone,” Thorpe continues. “Pressing lightly on the blade with the fingertips of your left hand, slide it around in a circular clockwise direction, keeping the blade flat.”

“Every half a dozen circles check the edge of the blade, because if the edge gets too fine it might chip — you want this to last. When you are happy with the sharpness, turn the blade and do new circles, this time moving the blade in an anti- clockwise direction.”

“Carefully test your blade to see how sharp or dull it is. When you’re happy, wipe your knife clean and make sure it is completely dry. If you are not going to use it for a while, rub a little oil on to it.”

Pictures: iStock