Knife protection while sharpening
With the handle everything is more or less clear and simple: wrap it with stretch film, seal the film with your fingers in the ricasso area and you can be sure that the handle is protected from splashes, dirty hands, and accidental contact with the abrasive. And you also need to understand that when sharpening, you can scratch the bolster. Therefore, if there is any doubt, it is better to secure your knife.
With blades everything is more difficult because sharpening is carried out with the help of water, oil, special liquids. All this is mixed with spent abrasive, metal particles, and these particles have the hardness of the blade. When sharpening with diamonds or borazon "on dry" the situation is slightly better, but diamonds and borazon also tend to break out of the bond, and the removed metal needs to go somewhere. Lots of people simply take a napkin and wipe everything off the blade. This is done more than once or twice during sharpening. As a result, the abrasive accumulates in the napkin and we get, probably, the most common cause of scratches on the blade, because the abrasive does not care what's the hardness of the steel, the content of vanadium, machine satin, or hand-operated one. It scratches everything. And if during the sharpening process you do not notice scratches, it does not mean that they are not there, sharpening is usually carried out under artificial light, and daylight will show all the flaws. And there are cases when even experienced knife-makers, sharpening a ready-made knife, received such problems before sending.
As practice shows, the probability of scratches on the bevels when sharpening on the slide table is higher than in the clamps, even if the blade is completely covered with tape, and if you use magnets, the risk of leaving traces is even higher. Therefore, if possible, the blade is carefully taped, and the usual masking tape is not the best choice, take a PVC tape.
When sharpening with clamps, the above problems are easily avoided. Just follow a few simple rules: do not wipe the blade with a napkin, do not brush the dirt off the blade with your fingers. During sharpening the blade touches only abrasive. As the blade and the bevels become dirty, the suspension is removed with water using a sprayer. The jet should be directed from the spine to the cutting edge, all this flows into the prepared container. Abrasive washed off in this way does not scratch the blade! In this case, the blade is taped only partly where it will be clamped by the jaw. Using a sprayer, we not only reduce the risk of damage of the blade to zero but also avoid the tedious taping of the blade completely, repeating the bizarre curves of the cutting edge, thereby saving us so valuable time.