This month's topic is sharpening and sharpening stones. This article isn't intended to be the ultimate sharpening guide, just provide you with the basic knowledge to get started. There are excellent reference books out there written by much more knowledgeable people than me. Check them out, but more importantly, sit down, grab your knives, chisels and plane blades and sharpen.

For the majority of hand tool sharpening there are four different kinds of material; oil, water, ceramic and diamond stones. They all can give you excellent results, but they cut at different rates and need slightly different techniques. I've learned over the years that the best way to get really sharp edges is to sharpen often to reduce the amount you have to remove and just as importantly, to keep in practice. The more often I sharpen the better I get and the easier it becomes. Be patient and match the right angle to the blade's use. In addition I'll mention strops for final honing of extremely fine edges.

General information
The sequence of sharpening is the same whichever type of stones you use. Coarse to remove nicks, shaping or re-beveling, medium to re-sharpen and fine to hone the edge. Each stage is replacing deeper scratches with finer ones. That's why a coarse stone leaves an almost frosted look to the metal, while a superfine would create a more mirror-like finish. An 8000 grit stone or stropping with leather puts a final hone on an edge removed even the finest of scratches.

Always remove any burr created by sharpening. This is an extremely thin edge of steel, which curls off the edge. If it isn't removed it will break off and leave you with a dull blade. Final sharpening into the edge instead of away from it and honing cross the back of the blade, will also help prevent this.

When sharpening make sure you are putting the proper bevel angle on the blade. Each blade and each use has a particular angle, which works best. Keeping the bevel close to the optimum will give you the best results.

Common Sharpening Angles Knives 5 deg both bevels Chisel, Paring 15 - 20 deg Chisel, Utility Bevel Edge 20 - 25 deg Chisel, Firmer / Mortising 30 - 35 deg Plane, Standard 15 with 10 back bevel Plane, Low Angle Softwood 15 with 5 back bevel Plane, Low Angle General 20 with 5 back bevel Carving Gouge 25 deg Carving Knife Edge 15 to 20 deg Turning, Roughing Gouge 45 deg Turning, Bowl Gouge 40 deg Turning, Skew 70 skew, 12-15 bevel Turning, Scraper 25 deg Turning, Parting Tool 30 - 50 deg Drill Bits, metal 135 deg

Oilstones Oilstones have been the traditional choice for western woodworkers. They can be naturally occurring or composite materials, with oil used as a lubricating slurry. The slurry helps to improve the cutting action, plus helps prevent material from building up in the stone and causing glazing. Manufactured stones are usually divided into coarse, medium and fine grits. Natural stones are usually divided into soft and hard. Natural stones tend to cut slowly and require patience to get the best results. General-purpose stones are flat and can be 4" to 8" long and 1" to 3" wide and there are combination stones available, which have different grit sides bonded together. There are also stones for special purposes, like shaped carving slips, gardener's stones or pucks for axes, even small stones with a groove for fish hooks.

Water Stones These stones have been the traditional choice in Japan and over the last 20 years they have attracted a large following in the west, myself included. These stones are softer and wear more quickly than oilstones, but they cut faster. They can be natural or manufactured, but both cut and work in the same way. They are usually soaked in water before use to flood the air spaces. Water is added as needed to act as the lubricant and create the cutting slurry. Like oilstones they come in a variety of shapes and sizes. Standard flat stones, some with two grits bonded together and shaped carving slips.

Ceramic Stones Ceramic stones normally come in various diameter rods set into a rack. The rack holds them at a 5 to 10 degree angle from vertical. This way you just run the blade downward as if you were slicing bread. Some versions have discs, instead of rods, set into a handle and you pull the knife through. The interlocking discs create the proper angle. All ceramic sharpeners are great for quickly putting an edge on a dulling blade, however they are not intended for removing nicks, taking down a shoulder or re-shaping a knife. There are also ceramic pucks out there but they are harder to find. I've seen these used to round freshly cut tile edges as well.

Diamond Stones Diamond stones are fast becoming the sharpeners choice. They cut very fast even on very hard steels, you can use them dry or with water and they last much longer. Grits in diamond stones are normally coarse (~180), medium (~250), fine (~600), and superfine (1200). The key with diamond stones is making sure you get one with a flat and stable base, whether steel or plastic is used. Smaller hand held units are available, which are perfect for honing router bits, drill bits and small knives. There are also round shaft style, which are perfect for small knives, gouges or knives with the hard to sharpen serrated edges.

Strops Stropping is a term for burnishing a steel edge with leather covered with a rubbing compound. Old-fashioned Barbershops still have a leather strop hanging from their chairs for those customers wanting a shave. They would strop the razor before starting and once or twice during the shave. This polishing removes even the finest scratches and puts an excellent finish on a blade. The drawback is that stropping, especially by hand requires a great deal of practice and a certain amount of finesse in order not to ruin all the work you did previously with the other stones. Because of the already fine edge on the blade you have to burnish away from the edge or it will bite into the leather. When learning how to strop, go slow and be methodical. Test the edge often to see how you are doing.