Step 1: Present students with a general overview of the CNC milling machine. Videos could be shown of different machines being used in different industries (electronics, automotive, aviation, marine, etc.)

Step 2: Narrate and discuss any experiences of working with a CNC milling machine.

Step 1: Present students with a summary of activity 1.

Step 2: Illustrate the different machine parts of a CNC milling machine. Including; The machine table, ball screws, axes drives, spindle, spindle drive, rails, ATC, tool magazine, MCU, HMI, coolant, oil, electronics cabinet…

Step 3: Ask students to individually sketch and label a CNC vertical milling machine. 

Step 1: Present students with a brief summary of activity 2.

Step 2: Show the students the different milling machine cutters including; a face mill, an end mill, a slot drill, a ball nose cutter, a twist drill, a spot drill and a chamfering cutter. Show the students the cutter geometry. (Students do not need to learn the mechanics behind the cutting process but only to know that the cutter geometry is different for different materials.)

Step 3: Show the students the different cutter materials, solid cutters and cutters with replaceable inserts. Different cutter coatings are also shown and the advantages of different coatings are discussed. Typical cutter prices are also of interest to students.

Step 1: Present students with a brief summary of activity 3.

Step 2: Present students with the cutting parameters in milling. Cutting parameters include; RPM, feed, type of cutter, cutter material, depth of cut, the width of cut, feed per tooth and cutting speed. Up-milling and down-milling are also discussed and a list of advantages and disadvantages is compiled.

Step 3: Students are presented with 2 ways to decide the cutting parameters - either by using a specialised app or by using machining charts and performing a calculation. Both ways are described and discussed in detail.

Step 4: Divide the students into 2 groups, giving them an example where stock material needs to be machined. Group 1 will calculate the machining parameters and Group 2 will use the app. The results will then be compared with each other. Another example is repeated and the student groups now swap methods.

Step 1: Show the students how to switch on the machine, health and safety labels - what they mean and why are they important.

Step 2: Show the students the different machine modes, software menus and how to move the machine axes using the jog and hand wheels.

Step 3: Show the students how to set up the tool magazine and label the tools in the machine’s tool register.

Step 4: Show the students how to align the work-holding device to the work table and secure it in place. A dial indicator is needed for this. Then show them how to align and secure stock material ready for machining.

Step 5: Ask students to operate the CNC machine in MDI mode. First by facing the stock material and then other operations such as peripheral milling and cavity milling. It is good that they try both up milling and down milling and the surface finish of both cuts is compared.

Step 6: Show the students how to remove the workpiece and how to clean the machine from the generated swarf. Students are encouraged to collect samples of swarf generated in different operations and compare them together. The colour, thickness, and length of the swarf are indicative of the health of the machining process. An appreciation of this is important.

• K2 To describe the work cycle and steps to operate a CNC machine

• S2 To set up a CNC machine properly