🔍 Key Concepts

• Machine bolt dimensions commonly specified in technical drawings • Difference between diameter, length, and thread specification • What information a mechanic needs to select the correct replacement bolt

💭 Think About

• If you were ordering a specific machine bolt from a catalog, what information would you need to be sure it matches the old one? • Which of the options gives enough detail that two bolts described that way would be guaranteed to be identical in fit and function? • Does knowing only head size or cross section really distinguish one machine bolt from another of the same diameter and length?

✅ Before You Answer

• Check which dimensions are typically stamped or listed in bolt specifications (think: 1/2"–13 × 2"). • Verify whether thread information is considered part of the basic description or an extra detail. • Ask yourself: which option would a machinist or engineer actually write on a drawing or parts list for a machine bolt?