1. Learning objectives: -
Bigger picture: -
Know about engineering processes used to produce modern engineered products
Learning objectives: -
Be able to explain what is meant by the term secondary machining
Describe a range of secondary machining techniques
Success criteria: -
Provide a definition for different machining operations
Correctly identify the sequence of machining for turning, milling and drilling.

2. Turning
Turning involves the use of the lathe to produce a given shape, usually cylindrical.
Lathes have one thing in common: the work piece is held in a chuck and rotated while being machined to shape and size using a cutting tool.

3. Lesson task 1: Look at the common machining operations for lathe work
Match up the operation with the description:
Operation:
Facing off
Drilling
Parallel turning
Taper turning
Parting off
Description:
A process used to cut off the work piece to the required length
Removing material from the outer diameter of the work piece while maintaining the same size along its length
Removing material from the end of a work piece to leave flat or square surface
Removing material from the inside of a work piece using a drill bit
A process used to create a conical shape by feeding a tool at an angle to the length of the work piece

4. Milling
Milling is a process used to shape products by removing excess material to produce a range of simple and complex shapes.
A milling machine has a spindle that holds a rotating cutter in place. The work piece will be clamped to a table or held in a vice and fed under the cutter to form the desired shape.
There are 2 main types of milling – horizontal and vertical.

5. Lesson task 2: Look at the common types of milling tools
Match up the tool with the function:
Operation:
Face mills
End mills
Slot drills
Slitting saws
Description:
Discs with saw teeth around the perimeter designed for cutting deep thin slots into the work piece
A type of end mill designed to plunge into the work piece like a drill then be moved across to create a groove
Cutter with multiple cutting tips – often called inserts – designed to move across the face of the work piece
The most common tool used in milling, this has cutting teeth at one end and along the side

6. Drilling
Drilling is a process that creates circular holes in a work piece.
The cutting device is called a drill bit.
It usually has a shank that allows it to be held in a drilling machine.
To drill a satisfactory hole in any material, the correct type of drill bit must be used.
This is probably the most common machining operation you will perform.
Good quality drill bits can be expensive but the key to good drilling is keeping the cutting edge sharp.

7. Lesson task 3: Look at the common types of drilling tools
Match up the tool with the correct picture:
Tool:
Centre drill
Tap
Countersink
Twist drill

8. Drilling The drill bit is placed into the chuck
The chuck is tightened with a chuck key and the guard is positioned
The work piece is clamped into a vice underneath the drill bit
The drill is switched on
The handle is slowly pulled down
The drill bit is gradually forced through the material
The lever is raised
The drill is switched off
Drilling

9. The tool is located in the tool holding device , tool post or tail stock
The work piece is secured in the chuck, face plate or work holding device
Coolant if required is switched on and directed onto the work piece
Safety checks are undertaken, ensuring all guards are in place
The tool is brought into contact with the work piece to produce the desired features
The tool is removed from the work piece and a safe procedure is followed to shut down the machine
Turning

10. Milling The tool is located in the chuck
The work piece is secured in the work holding device
If required coolant supply is switched on and directed onto the work piece
Safety checks are undertaken including guards in place
The tool is brought into contact with the work piece to produce the desired features
The tool is removed from the work piece and a safe procedure is followed to shut down the machine
Milling