Lesson 1 - Principles of Machining
Topics:
Machine tools; Metal cutting tools; Properties of metals; Case hardening; Cutting metals; Cutting fluids; Speeds and feeds; Chip shape and disposal
Learning Objectives:
– Name the two main classes of machine tools.– Tell how to identify ferrous and nonferrous metals.
– Explain methods of identifying steels.
– Define the following terms: tensile strength, compressive strength, ductility; and malleability.
– Explain various heat treating processes used with metals.
– List the functions of a cutting fluid.
– Explain how to change sfpm to rpm.
– Describe the information you can gather from chip color and shape.
Lesson 2 - Layout Work and Shop Safety
Topics:
Shop drawings; Scribing lines; Calipers; Measuring angles; Surface plates, gauge; Making a layout; Shop safety
Learning Objectives:
– Describe the tools commonly used for layout work in the machine shop.– Explain the function of a surface plate.
– Define the terms bolt circle, pitch chord, and centerline.
– List the steps involved in laying out flange holes.
– Explain shop safety practices relating to eye protection, chip removal, and tool handling.
Lesson 3 - Setup Tools
Topics:
Holding devices; Supporting the workpiece; Rests; Step blocks; V-blocks; C-clamps; Angle plates; Hold-downs; Magnetic chucks; Safety
Learning Objectives:
– Explain how to hold and drive work held between centers on a lathe.– Explain how to hold lathe work in a chuck, and how to mount and remove a chuck from a lathe.
– Define the term swing as it relates to a lathe.
– Tell how to hold oddly shaped workpieces on a lathe
– Explain when each of the following is used: collet chuck, steady rest, and follower rest.
– Explain how each of the following is used to hold work on a machine table: T-slot bolts and clamps, step blocks, V-blocks, C-clamps, angle plates,
– Tell when and how to use a vise to hold a workpiece.
– List safety precautions for setup tools.
Lesson 4 - Setup Measurement
Topics:
Working drawings; Dimensions; Precision; Tolerance; Using a steel rule, micrometer, vernier caliper, sine-bar, and gauge blocks
Learning Objectives:
– Explain the importance of having a working drawing when machining a part.– Define the terms section and sectional view.
– Name the three systems of dimensioning.
– Define the terms precision and tolerance.
– Define the term fit, and compare actual fit, clearance fit, interference fit, and transition fit.
– Name the simplest measuring tool in the shop.
– Explain how to hold and read a micrometer.
– Tell how to use a vernier caliper, sine-bar, and gauge blocks.
Lesson 5 - How to Grind Single-Point Tools
Topics:
Tool materials; Relief angles; Grinders and grinding wheels; Finishing, grooving, and threading tools; Carbide-tipped tools
Learning Objectives:
– Describe the various materials used for tools.– Identify the parts of a single-point tool.
– List important specifications for single-point cutting tools.
– Name the two basic types of grinders and explain how they are used to sharpen single-point tools.
– Explain the standard marking system for grinding wheels.
– Describe the best way to grind carbide-tipped tools.
Lesson 6 - How to Grind Multi-Point Tools
Topics:
Grinding a drill; Checking lips and relief angles; Thinning the drill web; Milling cutters; Cutter relief, clearance, end mills, and counterbores
Learning Objectives:
– Describe the construction of a twist drill, including identification of its parts.– Explain how to perform the following operations when grinding: check the drill lips, check the relief angles, and thin the drill web.
– List the three categories of milling cutters based on the way they are mounted on a milling machine.
– Name the most common type of milling cutter for maintenance work.
– Explain how to grind end mills, counterbores, and reamers.