It’s important to know how to sharpen knives, considering we use them so frequently in the kitchen, but also for recreational and hobby use. You shouldn’t worry about having well-sharpened knives and scissors at home: it’s easier to get hurt using a tool that doesn’t cut well and forces you to put in a dangerous amount of effort. In any case, it’s difficult to use blunt blades and they don’t cut regularly.
How to sharpen knives with a wet stone
You can use a wet stone to sharpen knives, which gently removes material and doesn’t heat the metal. It’s a special sharpening stone which must be soaked in water for 5 minutes before use. The stone has two surfaces with different grains, one with a lower grain (coarse grinding) and a higher one (fine grinding). Keeping the blade at a 10°-30° angle, pass the knife back and forth on the surface of the coarser stone using slight pressure for a few minutes, on both sides of the blade.
After sharpening, the knife must be finished to eliminate any burrs. To do so, turn the stone over and use the finer grain side, passing the knife back and forth like before.
To sharpen knives correctly, you must never press the blade against the stone too hard. Test the sharpness of the blade every now and then use your thumb to check it. To see if the knife cuts, place a sheet of newspaper on a surface and pass the blade over it while pressing very slightly: if the paper is cut, the knife is sharp. After grinding, the knife blade must be rubbed against a honing steel rod a few times with an alternating motion. This tool has a handle and a ribbed steel rod that serves to straighten the blade and remove any metal burrs. The last step is rubbing a cloth moistened with WD-40 Multi-Use Product on the blade, which counteracts any oxidation. Then dry the blade using paper towels.
Sharpening scissors
Now that we’ve explained how to sharpen knives, let’s see how to sharpen scissors. Scissor blades are not sharp at an acute angle, but have a shaped section that extends along two angles. The purpose of the grinding is to regularise and regenerate the angle adjacent to the flat surface in order to restore the inclination with which the blades meet. It’s best to have a “wet stone” electric grinding wheel to sharpen them.
Completely open the scissors, then place the blade against the stone of the wet grinding wheel in rotation, almost at a right angle (carefully observe the inclination of the face before grinding). Slowly move the blade from one end to the other and then move on to the other blade. Both blades must be straight, otherwise the object to be cut is pushed outwards.
Test the scissors by cutting a sheet of paper: if you notice some clearance between the two blades, rest the hinge of the scissors on an anvil and strike the central screw lightly with a hammer a few times so as to crush it slightly. Lastly spray a small amount of WD-40 Multi-Use Product around the joint area where the two blades are hinged to facilitate the scissors’ operation. To remove the burr from the blades and smooth the edge, you can lap the blades at home by rubbing the blades themselves, as if you’re cutting, on a bottleneck.
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