🔍 Key Concepts

• Difference between rake angles (on the top surface) and relief/clearance angles (below the cutting edge) on a lathe tool bit • How the top view of a single‑point cutting tool shows the relationship between the cutting edge, the tool shank, and the work • Where the nose or point angle is measured on a tool bit (around the very tip, between the side and end cutting edges)

💭 Think About

• From the top view in the illustration, what is angle A actually measuring between—two flat surfaces, or a cutting edge and a reference line? • Which of the listed angle names would normally be visible and measurable in the top view versus in the front/side views? • On a standard tool‑bit diagram, where would you expect to see the nose angle labeled compared to the side relief or side rake angles?

✅ Before You Answer

• Confirm whether angle A is on the top surface of the tool or along the side face below the edge—this tells you rake vs relief. • Check if angle A is located at the nose (tip) of the tool or along the length of the cutting edge. • Match the location and direction of A in the top view to standard lathe tool‑bit nomenclature diagrams in your study materials before choosing.