Regarding chamfers and fillets, what guideline aligns with simplifying manufacturing?

• A. Include them
• B. Omit them
• C. Always full-radius
• D. Use only on internal features

Answer: (B)

Omitting chamfers and fillets when they aren’t required keeps the part geometry simple and reduces manufacturing steps, tooling, deburring, and inspection needs. This makes the production process faster, less costly, and less prone to variation, which is the essence of designing for easier manufacture. If a chamfer or fillet isn’t essential for fit, clearance, assembly, or strength, leaving the edges sharp or near-true with basic milling or turning can streamline production. Of course, if a chamfer or fillet is needed to avoid sharp edges for safety, to improve assembly, or to reduce stress concentrations, it should be added only when those functional needs justify the extra work.

Including them would complicate the process and increase cost without added value in many cases, a full-radius feature isn’t a universal rule and isn’t about simplification, and restricting use to internal features is too narrow and doesn’t reflect when external edges might also benefit from simplification or when they’re unnecessary.