Is it advisable to use mirror-image parts in a design?

• A. Always
• B. Often
• C. Avoid
• D. Never

Answer: (C)

Designing with mirror-image parts generally introduces unnecessary complexity and risk. When a part is a reversed copy of another, orientation becomes a source of potential errors during assembly, which side goes where, and which way a feature faces. This leads to more complex tooling, separate manufacturing setups, and separate drawings and bill of materials, all of which raise cost and the chance of misassembly. The safer approach is to make parts interchangeable and orientation-insensitive where possible, or to clearly distinguish left and right versions with proper labeling and documentation if they must exist. By aiming for a single, interchangeable part or using features that enforce correct orientation, you simplify production, inspection, and inventory management. There are situations where left/right variants are truly needed, but as a general practice, avoiding mirror-image parts minimizes risk and cost.