Guide to Sharpening (work in progress)

Ever had a knife that no matter what you did it just would not get sharp. This Guide is something I am putting together to make sure you never have this problem again as long as you have the right materials. At this moment in time THIS IS A WORK IN PROGRESS.(Last change 5/06)The first thing that you need to learn is edge geometry. I will make this as simple as possible.Edge Bevels- An edge bevel is usually present on modern knives. It is the usually flat very small angle at which the steel is cut on a blade in order to give it a sharp edge. You can locate the bevel on your knives by looking at the blade edge side. You will see probrably only a couple milimeters till u see a line that runs the extent of the edge.Grinds: a: hollow grind - a grind that is concave in nature. knives with a hollow grind tend to be the very best at getting the keenest of edges, but does tend to be a more brittle edge. The best performance with this type of grind is a surface or cut that does not go very deep as the deeper the cut the heavier the drag. There is always an edge bevel on knives with this grind. straight razors use this grind and have no edge bevel. b: flat grind - a grind that is flat in nature and sometimes all the way to the edge and lacks an edge bevel. Flat grinds are probrably the best "utility" grind there is. It is very easy to sharpen and has a fairly durable edge. c: convex grind - a grind that is of course convex in nature. These grinds also will lack an edge bevel at times. These are very durable edges, but can be extremely difficult to acheive and to sharpen in the field. Better have some time on your hands if you want to master this one. you will sometimes see axes with this grind. d: chisel grinds - a grind that is ground on one side usually with an edge bevel on only one side as well. Can be a tough grind to get used to even if you can sharpen other types of knives.Things to note:Modern Steels- Many modern steels of today have ultra hard gepounds such as tungsten carbide which can create a problem when trying to use certain stonesSoft Steels- You would think this would mean they are easier to sharpen. Guess again!Anti-corrosion and edge retention- It seems that along with anti-corrosion there gees a challange with sharpening. Chromium and Tungsten Carbide can make sharpening a lot tougher. Some show steels such as 420 J2 have very little carbon which helps detour corrosion, but ruins edge retention.Titanium- A very tough alloy, but is softer than steel. Titanium is usually used only by modern specialty military knives due to its non magnetic properties and extreme toughness. Titanium is almost imposible to bend or break however the edge does tend to roll fairly quickly especially with large knives if used for chopping or if it is used to cut hard materials such a wood.High-Tech Ceramic Blades - The edge holding capabilities of ceramics far surpass any steel of today and without abuse can hold an edge up to 10 times longer than ANY steel bladed knife. There are however some drawbacks such as brittleness and knives made of this material are nearly impossible to sharpen with manual sharpeners. The ceramics used in modern knives is the same material used to coat the outside of our space shuttles stations ect. Some say that these knives can be sharpened with diamond sharpeners, however in my experience this is very time consuming, and the utmost care must be taken to make sure every stroke on the stone is the same angle. This is true with steels as well, but the hardness of ceramics makes this even more important. I highly suggest you do not manually sharpen these knives and let the factories that made the knife do this job for you.Chisel grinds - When sharpening chisel grinds you sharpen only on one side of the blade. This develops a more severe burr than any other type of blade. Also I regemend not using angles that will take the steel too thin on the edge. Since the edge on this type of blade is not symetrical this weakens the edge quite a bit and tends to be brittle. Depending on the steel used in the knife a burr can usually be taken care of with a leather strop or newspaper. Scissors are also sharpened the same way as a chisel ground knife, but at a different angle. There are more details on burrs in the very next section.Burrs - Burrs usually develop when taking off lots of steel. It also happens when sharpening soft steels and titanium blades. This can usually be taken care of by stroking the blade edge toward the spine of the knife between 10-20 times on each side with a leather strop or with rolled newspaper. On high tech steels (especially ones using tungsten carbide) it can be helpfull to use an extra-fine CERAMIC sharpener, and using the same technique as when using a strop.Direction of strokes when sharpening - This is a matter of debate, but with very extensive experience sharpening all types of knives and other edged items I feel it is best to act as if you are trying to slice a thin layer off the top of your stone. Doing this helps keep annoying burrs to a minimum.BEVEL ANGLES: Knives: Many angles can be used to sharpen knives and depending on your usage of the knife will determine which angle you should use. I will go into further details on this at a later date, but should be fairly soon. Keep checking back for this info.1. Kitchen Cutlery (Note: cleavers will be covered under heavy choppers)
A. Paring Knives -
B. Boning Knives -
C. ChefKnives -
D. Santokus and dicing knives -
E. Sushi Knives -2. Pocket Folders -
A. Work Knives-
B. Gent's Knives -
C. Tactical Knives -3. Heavy Choppers -
A. Machettes -
B. High End Kukri's, Bowies, ect. -
C. Cleavers -Straight RazorsAxesScissorsKatanas and traditional japanese knives and swords