🔍 Key Concepts

• Locational interference fit versus clearance fit – what must be true about shaft diameter vs. hole diameter? • How thermal expansion or machining (drilling/turning) changes the relationship between those diameters. • Look closely at the actual sizes shown for piece B: 0.255 in and 0.250 in.

💭 Think About

• For piece B as drawn, is the shaft currently larger or smaller than the hole? What type of fit does that create? • Which option would change the situation so that, after assembly, the shaft cannot slide freely in the hole but must be pressed or shrunk into place? • Compare each choice: does it make the hole bigger or smaller, or the shaft bigger or smaller – and how does that affect whether you get clearance or interference?

✅ Before You Answer

• Be sure you know which dimension in the sketch is the shaft diameter and which is the hole diameter. • Verify whether an interference fit requires the shaft diameter to be greater than the hole diameter, or the other way around. • For the heating option, think about what happens to metal dimensions when temperature changes and what the diameter would be at assembly versus at normal temperature.