When tolerances must be precise, which grinding technique should be used?

• A. Cross grinding technique
• B. Grinding by eye
• C. Belt sanding
• D. Hand polishing

Answer: (A)

Precise tolerances demand a controlled, repeatable material removal process. The cross grinding technique achieves that by moving the grinding wheel across the workpiece in multiple directions, which creates a uniform stock removal and reduces directional errors. This approach helps produce a flatter, more parallel, and consistently sized part, so final dimensions stay within tight limits and surface integrity is preserved.

Grinding by eye relies on sight and feel, which introduces variability and makes it easy to miss small dimensional differences. Belt sanding removes material quickly but can be less uniform and tends to leave waviness or heat-affected zones, making it unsuitable for tight tolerances. Hand polishing is a finishing step that removes minimal material and depends heavily on operator feel, offering little control over exact dimensions.

So, when exact dimensions matter, cross grinding provides the precision and consistency needed to hit those tight tolerances.