1. INDUSTRIAL TECHNOLOGY-METAL ASSOCIATED THEORY
TOPIC 4.
MACHINE TOOLS & MACHINING
INTRODUCTION
FIXED MACHINES
DRILLING OPERATIONS
MILL DRILL
CENTRE LATHE
CUTTING TOOLS
LATHE ACCESSORIES
TURINING OPERATIONS
BENCH GRINDER
MISCELANEOUS POWER TOOLS

2. INTRODUCTION Machine tools may be free-standing, e.g., lathe assembly
At the end of the 19th Century the Industrial Revolution launched many new ways of manufacturing. The introduction
of the ……………………. line, and the
development of ……………………… tools enabled work to be performed faster and sometimes more accurately. The use of assembly lines and machine tools to produce large quantities of identical items
 is called ………… …………………….
Machine tools in modern workshops are
powered by ……………………., either directly or via air compressors.
Machine tools may be free-standing, e.g.,
…………..
 ………………….. and ……………………….
 or portable, e.g., …………………….. and
 …………… grinder. Battery powered electrical tools are known as
……………… power tools, and are popular on building sites, or for travelling repair and maintenance personnel. Voltages range from 7.5 to 18 volts.
lathe
assembly
bench grinder drilling machine
machine
electric hand drill
angle
cordless
mass production
electricity

3. FIXED MACHINES COLUMN DRILLING MACHINE DRILL BITS TWIST DRILL
PULLEY GUARD
General purpose drilling and for countersinking to a specific diameter.
MOTOR
REDUCED SHANK TWIST DRILL
FEED LEVER
CHUCK
COLUMN
This drill allows larger diameters to be drilled using a smaller capacity chuck.
TABLE
TABLE
ADJUSTMENT
COMBINATION CENTRE DRILL
Precise centring of holes drilled in the lathe.
COUNTERSINKING DRILL
Countersinking existing holes and deburring.

4. DRILLING OPERATIONS Spindle motor Fast spindle speed
Spindle motor
Fast spindle speed   
Slow spindle speed
What type of steel are drills bits made from?
 ………………………………………….
 The general rule for drilling is:
Small drill ……………..speed.
Large drill …………….. speed.
 Why is it important to clamp work that is being drilled?
HSS (High Speed Steel)
fast
slow
Why is it important to use a centre punch before drilling?
When do you use cutting fluid?
   
What is a pilot hole, and how do you calculate the size of a pilot hole?
The drill may catch the work as it breaks through, spinning the work around and may cause a serious injury.
Prevent the drill running off centre.
Drilling large or deep holes in steel.
Do not use excessive force.
Wear eye protection.
Remove metal shavings with a brush.
Avoid bent, blunt or damaged drill bits.
A small hole drilled before a larger hole. It’s diameter should be the width of the web.

5. MILL DRILL
This machine is a combination milling and drilling machine. In addition to holding a variety of different drill pieces it can also be used to machine flat surfaces on metal, cut grooves in shafts, and perform a variety of operations in the horizontal and vertical planes.
motor
Milling
cutter
Vertical feed
Horizontal feed
Horizontal feed

6. THE CENTRE LATHE & TURNING
The centre lathe is used for a variety of machining processes, including facing, turning between centres, drilling, knurling etc. It can hold various shaped materials using different chucks.
How should you be dressed when using the lathe ?
What particular precaution should be taken with the chuck key?
Why is it important not to interfere with the operator?
Safety glasses
Leather covered shoes, apron tied, tie removed, loose clothing tucked in, and safety glasses. No jewellery.
Apron tied
Remove the key immediately after fitting or removing work from the chuck to prevent it being ejected.
A loss of concentration can result in a serious accident.
Leather covered shoes

7. THE CENTRE LATHE back gears lever handwheel headstock clamp
dead centre
tool post
tumbler
gears
tailstock
pulleys
live centre
compound rest
guard
bed
Automatic feed lever
apron hand wheel
quick change
gearbox
feed rack
cross slide
stand

8. CUTTING TOOLS Tool post screw Tool post clamped short Tool post
Tool holder
T slot
Tool post clamped short
Cutting tool at centre height
Tool post ring
Right hand Round nose Left hand
Tool post wedge
Knurling tool
What are cutting tools made from?
When should a coolant be used?
High Speed Steel (HSS)
When taking heavy cuts or when a high quality finish is required straight from the cutting tool.
Typical knurling pattern

9. LATHE ACCESSORIES CHUCKS 3 Jaw self-centring chuck
Key inserted here operates 3 jaws simultaneously.
CHUCKS
Key inserted here operates this jaw independently.
3 Jaw self-centring chuck
4 Jaw Independent chuck
A general purpose chuck used for holding cylindrical and hexagonal work. A separate set of jaws (illustrated) can be fitted for large diameter work.
This chuck can hold square, octagonal or irregular shaped material. Each jaw can be reversed to suit the particular requirements.

10. LATHE ACCESSORIES Revolving Centre Boring Bar Parting Tool Holder
Used to support long thin work when turning between centres.
A small cutting tool fitted to the end allows holes to be enlarged or reamed.
Parting Tool Holder
Jacob’s chuck
A thin HSS blade attached to this tool enables material to be cut off in the lathe.
This tool, fitted to the tailstock allows material to be drilled along the central axis.

11. TURNING OPERATIONS
What special care must be taken when engaging automatic feed?
What is the purpose of the back gears ?
How is the size of the lathe determined?
Explain two methods that can be used to turn a taper.
Explain the difference between a roughing cut and a finishing cut.
 Roughing
Finishing
Automatic feed must be disengaged before the cutting tool collides with the chuck.
A secondary set of gears which reduces the speed of the main spindle. These are used when turning large diameter work or when knurling.
The maximum length of material that can be turned between centres and the maximum diameter material that can ‘swing” over the ways.
Offset the tailstock so that the work is at an angle to the axis of the lathe.
Adjust the compound rest to the required angle.
A deep, heavy cut that removes a large amount of material quickly, but leaves a rough surface.
A shallow or fine cut that removes only a small amount of metal and produces a smooth high quality finish.

12. BENCH GRINDER Eye shield Guard Tool rest Switch
What are grinding wheels made from?
 State two precautions to be observed when using the bench grinder.
How can uneven wear of the wheel be prevented?
How can grooves in the wheel be removed?
The two main types used in schools are aluminium oxide and silicon carbide.
Adjust the tool rest close to the wheel.
Stand to one side of the wheel when turning on.
Move the work from side to side across the face of the wheel.
A diamond pointed wheel dresser can be used to remove grooves.

13. MISCELANEOUS POWER TOOLS
This model has a keyless chuck, variable speed, and reversing action, enabling it to be used as a screwdriver as well as a general purpose drill.
Portable drill
Angle grinder
PRECAUTIONS
Use machine with both hands.
Direct sparks away from others.
Keep lead clear of the wheel.
Wait until machine stops before putting it down.

14. MISCELANEOUS POWER TOOLS
The portable saw
is useful for quickly cutting
tubular steel, angle iron, and
solid section up to  mm.
 It must be used with extreme care to avoid injury.
cut - off 20
Secure stock firmly in vice.
Apply firm but gentle pressure when cutting.
Wear eye and ear protection.
Warn students to avoid sparks before operating.
The cutting wheels are a composite of abrasive particles and reinforcing mesh fibre.
Disconnect the power, remove the guard, lock the shaft and loosen the securing nut.