|Grinding of Simple Tools - Course: Technique for manual working of materials. Trainees' handbook of lessons (Institut für Berufliche Entwicklung, 19 p.)|
When the workpiece is pressed against the grinding wheel which is rotating at a high speed (approximately 2800 rotations per minute), the abrasive grains by their irregular and sharp cutting edges scrape smallest chips from the workpiece.
After the abrasive grains have become dull they tear loose from the structure of the wheel making room for the next following sharp abrasive grains that continue the cutting operation.
Figure 6 - Effect of the abrasive grains
Thus the grinding wheel sharpens itself.
After sharpening a cutting edge of a tool, a burr is to be noted at the edge. This must be removed by whetting before the tool is used.