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The chipper tooth blade is fabricated from high carbon steel and is heat treated to provide a long lasting sharp edge. The pilot point of the blade is hardened and ground to a sharp cutting edge. To re-sharpen the pilot point use a 12 to 16 inch diameter disc grinder with No. 80 grit paper. Follow the angle of the point, grinding the edge straight on both sides. Be sure that centers are maintained as shown in Figure 1. When too much is ground on one side, the blade point will be off center as shown in Figure 2. Proper back clearance on the pilot point and the chipper tooth blade is essential as shown in Figure 1 and Figure 3. Hold the drill assembly upside-down in a vise. Using a file and/or file with sandpaper, remove all burrs from back of the chipper tooth blade and the pilot point.