🔍 Key Concepts

• Meaning of standard tap drill notation such as '10-24' in machine shop practice • How threads are specified on screws and bolts in the U.S. system • Difference between diameter size and thread pitch on a drawing

💭 Think About

• When you see something like '10-24' on a fastener or tap, what does the first number usually describe, and what does the second number usually describe? • Which of the choices is commonly used as a standard way to describe threads on screws and taps in technical drawings? • If you were selecting matching nuts and bolts, which of these values would have to match: number of holes, threads per inch, hole size, or tightness of fit?

✅ Before You Answer

• Recall that U.S. screw sizes combine a nominal diameter with a measure of thread spacing • Ask yourself which property is normally written as a plain number after a dash in fastener designations • Eliminate any options that are not a standard specification item when labeling a tap on a drawing