Sharpening Carving Tools
Bench Knives, Chip Knives, Flat Chisels
By L.S. Irish
Sharpening is not that hard and it is something every carver should know how to do for themselves. Your are going to need a couple of grades of sharpening stones, a strap and some rouging or compound, and a few sheets of newspaper. I personally prefer the ceramic stones we are currently carrying. Having used quite a few different varieties these seem to give me the best results.
Sharpening Stones and Strop
Sharpening stones are available in a variety of grits and created from a variety of mineral compounds. You will find them listed in the catalogs under the titles of Arkansas Wet Stones, Diamond Hones, Ceramic Stones, Japanese Wet Stones, etc. Some sharpening stones require a lubricant as oil or water, others do not. Read the instructions for use and care of your stones that comes from the manufacturer.
Again, my preference is the ceramic stone. They require no lubricant, so are used dry. Small in size, about 4 to 5 inches long they are easily stored right in with my carving tool, always within reach. Finally, but most important, they do not develop a sharpening gouge or dip from use. These stones always provide a flat surface thus creating a flat edge. They clean up easily with soap and water, removing any of the filings for the next use.
Many Techniques for Sharpening
There are many ways (techniques) for sharpening and the best one is to find something you are comfortable with and keep doing it! I say this first because ever time you change the technique you use to sharpen, you change the angle of the edge you are creating. That mean having to start all over each time to create a new leading edge to the knife. So pick one way and stick with it for a while. This means about 8 to 10 times … enough to really develop a good edge.
It has been my experience that no knife or chisel becomes perfectly sharp on the first honing. In fact, it often takes several sessions of sharpening then using the tools to finally achieve a razor sharp edge. So be patient with the technique you are trying. Sharpen some, whittle some, sharpen again … fairly soon you will realize that the tool has developed that wonderful cutting edge.
Coarse Stone, 800 Grit
I start with my brown coarse stone. The stone shown in the photo is a Japanese Wet Stone, 1000-grit, that creates a thick mud-like slurry as the blade is pulled across the water soaked stone.
Lay the knife on it’s side flat against the stone. Now lift the back edge of the knife slightly off the stone. Imagine lifting it just enough to be able to slide four or five pieces of typing paper under the back edge. This gives you an angle of about 10-12 degrees.
The tighter the angle to the stone the finer edge the tool will receive. Tight angles mean less steel biting into the wood. For any knife that is used to make stop cuts or line cuts I like a very tight edge. Chisels and gouges do not require that tight an angle so you may wish to lift these tools higher off the stone. These are sharpened around 20 to 25 degrees. Follow the manufactures angle as much as possible with a new tool. After you have learn how the tool “feels” in use you can easily adjust that cutting angle to fit your needs.
Pull the knife along the stone moving away from the cutting edge. When the stroke is complete turn the knife over and repeat for the other side. What you do to one side of a chip knife or bench knife your repeat on the other side. Now you are beginning to developed a double edge.
I think just about everyone has seen the American Old West movies where the barber is talking to the gunfighter, who is about to get a shave. As they converse the barber is honing the razor on a leather belt strop. It’s that flowing pull, flip, and pull again stroke for which you are looking.
Once you have developed a good edge, start any sharpening sections with the white fine grain stone. The coarse brown stone is only used to developed the angle, after that you only want to maintain that angle.
For straight chisels you want a single edge tool, not a double edge as on the bench knife.
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