When sharpening rotary blades, which condition should be avoided because it dulls the edge quickly?

• A. Too bevel (dulls quickly)
• B. Too blunt (poor cutting)
• C. Too sharp (causes chipping)
• D. Too light (ineffective)

Answer: (A)

When sharpening rotary blades, the edge geometry matters: you want a balance between a sharp cutting edge and enough strength to resist wear. If the bevel is too heavy or too open, the edge becomes very thin and weak, so it dulls quickly when it contacts grass, debris, or small stones. That fragility is what makes edge life short. In contrast, a blade ground too blunt cuts poorly, one ground too sharp can chip, and one that’s too light won’t cut efficiently. So the condition to avoid is an overly bevelled edge, which leads to rapid dulling.