How Can I Get My Knife Razor Sharp?
You can get your knife as sharp as a razor.
Razors are often used as a standard of comparison for sharpening. A razor does indeed need to be sharp in order to cut hair without damaging the skin, so on one level the comparison is useful. And the ability of a blade to shave hair has long been used as a measuring stick for determining sharpness.
Of course, razors are sharpened at much lower angles than knives typically are and this factors into the perceived sharpness of them. (See our article Detailed Discussion On Knife Sharpening Angles for an in depth look at the role played by different angles.) But sharp enough to be used as a razor is a reasonable goal for a knife sharpener.
This level of sharpness is only possible with the use of fine grits in the sharpening process. The smaller the grit particles, the more refined and even the edge will become. We recommend for the finest edge possible to go to a 9 or 10 on our sharpening stone grit chart. These abrasives will be able to polish the edge to a mirror like finish.
But before you run out and get a polishing stone or strop your blade, keep in mind that fine grits can only do their job effectively if they have a good base to work with. That is, the edge has to have been brought into shape properly with lower grits first. In fact, if we look at the grit size chart linked to above, it is usually required to have at least two stones spread across the range of grits, and even better to have three or more. In plain terms, you will need a coarse and a fine at the least, and if there is a medium in there, even better. This is why our Systems and Kits have at least two, and often three or four stones.
If you have trouble visualizing why coarser stones are also required to create the proper shape, check out our article Visualizing an Edge for an illustration.