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Sharpening Tools
One of the first things I do when teaching a boatbuilding class is to show my students how to sharpen their block planes and other edged tools. Watching a roomful of students struggling with dull tools is too much to bear; boatbuilding should be fun, and sharp well-adjusted tools are a pleasure to use.
I prefer to sharpen on a Japanese waterstone. I think these are easier to use and leave a better edge than an oil-stone, or Arkansas stone. A combination waterstone with a 1000-grit surface (coarse) on one side and a 6000-grit surface (fine) on the other is perfect for sharpening woodworking tools or even kitchen knives. These stones use water as a lubricant and should be soaked for a few hours prior to use. I simply store my stone in a water-filled plastic container.
A small block plane is the one edged tool that I think every boatbuilder should own; it is useful for trimming parts, cutting bevels, and a hundred other tasks. So I'll describe sharpening a plane's iron, or blade; most tools are sharpened the same way.
First we'll flatten the back; the back of the iron makes half the sharp edge, so this is important. Splash some water onto the coarse side of the stone and lay the iron on it, back face down. Sharpen it by pushing it up and down the stone in a circular motion.
- Use the entire stone; splash more water on the stone frequently and check often to see if the blade's back is smooth and flat. This may take some time if this is a new tool; they do a poor job sharpening blades at the tool factory these days. When you see that the stone has made contact with the entire back of the iron (look at the sheen) sharpen for 3 more minutes on the fine side of the stone.
Now we'll sharpen the front. Hold the blade against the course side of the stone so that it rests on its bevel; rock the blade slightly to get a feel for when it's resting squarely on the bevel. Move the blade back and forth on the stone making a long oval circuit. Keep your fingers close to the bevel and press down gently. Be careful that the iron remains at a constant angle with the bevel flat on the stone.
- When the entire bevel has been sharpened - look at the sheen made by the stone - repeat for 1 minute, or 20 up and down strokes, on the fine side. If you now draw your fingernail down the back of the edge you should feel a tiny burr or "wire" made by the thin metal edge bent back in the sharpening process. Now lay the blade on its back again and pull it down the stone one time to remove the wire. Finally, dry the iron. If you did everything right you can almost shave with this edge. Now that the blade is true and sharp, sharpen it often and the process will take only a few minutes.