Geometric tolerance affects assembly by?

• A. Only the color of parts
• B. Allowable deviation from nominal geometry; tight tolerances may require precise positioning and fixturing or vision-assisted alignment
• C. Only the material properties
• D. Only the weight of components

Answer: (B)

Geometric tolerance governs how much a feature’s actual geometry may differ from its intended shape and location. In assembly, this determines whether parts will fit together and align as designed. If a hole is smaller than specified or a mating feature is out of true position, the parts may not assemble or may have unwanted gaps or misalignment. When tolerances are tight, achieving proper fit often requires precise positioning and fixturing, or even vision-assisted alignment to verify and guide placement. Conversely, looser tolerances ease assembly and reduce cost, but can compromise performance.

Color, material properties, and weight don’t define or constrain geometry in the same way; they affect appearance, strength, and handling, but they aren’t what geometric tolerances specify.