Sharpening My own preference is for the traditional whetstone and the one in the illustration below is a Japanese product with a 1000 grit stone sandwiched to a 6000 grit stone for course shaping and fine sharpening respectively. This was bought about 25 years ago and is showing signs of wear and tear on the corners and gouging on the surface when I don't get the angle right. From time to time the surface is 're-dressed' by a local engineering firm using a diamond linisher to get rid of surface blemishes. The width of the stone is less than the length of the knife blade so the knife is held at an angle to the axis of the stone rather than at right-angles and alternating between a 10 to 4 position and a 20 to 2 position if you can visualise the hands of a clock. The angles used can be seen in the surface of the stone, indicating that it is in need of an urgent 'dressing'! The whole length of the blade should be sharpened at once rather than a slicing motion as you sharpen; the straight edge of the blade needs to be kept dead straight as even the tiniest of indentations in the edge will affect the ability of the knife to cut smoothly. The knife should be sharper than a razor; it's easier to cut yourself with a blunt knife than a sharp one.
A good test for sharpness is to hold the edge of a newspaper and balance the knife handle on the finger of your other hand with the blade resting on the edge of the paper. When drawn across the paper it should slice through it without any pressure. I'll take a picture of the procedure and put it up here soon; it will probably be easier to follow. Another measure of sharpness, although I don't know if it was a trick by the props department, was demonstrated by a scene in the film 'The Bodyguard', recently shown on television in the UK. Our hero, who happens to have a sword pointed at his chest, removes the silk scarf from the neck of Whitney Houston, throws it up in the air and as it falls on the blade is neatly sliced it two. Japanese sword-makers will routinely finish off blades with a 12000 grit stone so perhaps it really did happen. From a cost point of view it's probably cheaper to stick to paper! In recent years diamond whetstones have become popular as they don't require the maintenance of a traditional stone and models are available that come with sharpening guides that remove the guesswork in trying to keep to a particular angle. For these stones a guide is highly recommended as it is all too easy to abrade the tips of your fingers on the edges of the stone. As to what angle you should aim for, try to keep to the manufacturers original angle but the exact angle on an older knife is not critical and anything between 20 and 25 degrees is acceptable. For stropping your knife between sharpening you can take the luxury route with a proper barber's leather strop or just use the thigh of your trousers! If they are made of a fairly coarse cloth the end result will be just as good. Unlike sharpening, where the edge of the blade is moved against the stone, stropping should be done with the edge of the blade trailing. Both sides, even for a single sided knife, should be worked in a backwards and forwards motion. The other way round will be very bad for your health! A point I forgot to mention in the original text above is the need to immobilise the stone when in use. Although excessive pressure is unnecessary, from a safety point of view it is probably best if the stone and knife are prevented from going off at an angle if the knife should catch. A simple solution is a wooden stop that you might remember from woodwork classes at school, a drawing of which is included below.
A piece of timber perhaps six by nine inches has battens fixed at each end on opposite sides and in use one end is hooked over the edge of the table or worktop and the stone is held against the other end to prevent it from moving away. Another point omitted is the need to clean the stone after each use. Putting under running water and gently scrubbing with a nailbrush or toothbrush will remove the fine sludge that is produced with each sharpening. Left to build up this will clog the surface and eventually reduce the efficiency of the stone.
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