Cutting Tool Classification

1.Single-Point Tools • One cutting edge • Turning uses single point tools • Point is usually rounded to form a nose radius 2.Multiple Cutting Edge Tools • More than one cutting edge • Motion relative to work usually achieved by

rotating • Drilling and milling use rotating multiple cutting

edge tools.

Cutting Tool Classification

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Milling Cutters

Side and Face Cutter Slab Mill

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Cutting Tool Characteristics Hardness at elevated temperature (hot hardness)

Strength

Wear resistance

Permanent indentation resistance

Toughness

Repeated operations by retaining shape

No breakage or chipping off

Wear Resistance

Increased tool life

Chemical Stability or Inertness

Work piece or coolant

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Cutting Tool Materials

Carbon and medium alloy steels

Easily shaped & reshaped -- no high hot hardness

• Drill bits

• Taps

• Broaches

• Reamers

High Speed Steel

High speed cutting

High toughness

Resistance to fracture

• Tungsten/molybdenum tools

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Cutting Tool Materials

Cast cobalt Steel

Good wear resistance

Hot hardness

Carbide inserts

Tungsten & Titanium carbides

Very high hardness

Very high resistance

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Metal Cutting Operations

Orthogonal & Oblique

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Metal Cutting Operation

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Heat Generation

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Cutting Conditions Relative motion between the tool and work

The primary motion cutting speed

The tool moved laterally across the work, slower motion, feed

Penetration of the cutting tool below original work surface, depth

of cut

Collectively, speed, feed, and depth of cut are called the cutting

conditions

For certain operations, their product can be used to obtain the

material removal rate for the process:

RMR = vfd

where

— RMR the material removal rate in mm3/s, (in3/s),

— v the cutting speed in m/s, (ft/min),

— f the feed in mm, (in),

— d the depth of cut in mm, (in).

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Tool Orientation Operation Performed

Straight turning

Shoulder turning

Facing

Chamfering

Forming

Parting off

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Types of Lathe Tools

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Classification of Lathe Machine

Maximum diameter of work piece

machined or swing

Maximum distance between head stock &

tail stock

Length of the Bed

Components of Lathe Machines1. Head stock (spindle, speed change lever)2. Tail stock (spindle, lock bolt)3. Carriage (tool post, top slide, taper attachment, compound rest, cross slide, apron, lead screw etc.)4. Bed5. Legs

Tools of Lathe Machine1. Left hand side tool (facing, turning & taper turning)2. Right hand side tool3. Outside threading tool (external threads)4. Boring tool (internal facing, increasing hole & smoothing)5. Left side threading tool6. Parting tool (separating work piece from other material)7. Knurling tool (hard work piece is pressed with it)8. Revolving tool (supports work piece)9. Drill chuck (to move the hole)

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Speeds for Turning Operation on Lathe

Aluminium alloys 200 - 1000 rpm

Cast iron 60 – 90

Copper alloy 50 – 700

Steels 50 – 500

Stainless steel 50 – 300

Titanium alloys 10 - 100

Accessories of Lathe1. Gear box (lead screw, feed rod, clutch, coolant pump)2. 3 jaw & 4 jaw chuck3. Face plate4. Driving plate5. Fixture6. Travelling steady7. Dead centre8. Revolving centre

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Centre Lathe

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Heavy Duty Lathe

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Tool Room Lathe

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Bench Lathe

CNC LATHE

Computer Numerical Controlled (CNC) machines are being used in every kinds of manufacturing processes. In a CNC machine, functions like program storage, tool offset and tool compensation, program-editing capability, various degree of computation, and the ability to send and receive data from a variety of sources, including remote locations can be easily realized through on board computer. The computer can store multiple-part programs, recalling them as needed for different parts.

CNC LATHE

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Floor Type Boring Machine

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Single Column Vertical Boring Machine

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Double Column Boring Machine

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Shaper Machine

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Double Column Planning Machine

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Single Column Open Side Planner

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Shaping Machine

Bench Drill

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Hand Feed Drill Machine

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Power Feed Column Drilling Machine

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Radial Drilling Machine

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Multi Spindle Drilling Machine

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Turret Drill Head

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Types of Drill Points

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Horizontal Milling Machine

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Vertical Milling Machine

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Horizontal Spindle – Reciprocating Table Surface Grinder

Single-Spindle Automatic Screw Machines

Few More Precautions for Lathe Machine

1. Machine should be operated by authorized person.

2. Checkup for elect connections and lubricant before working on machine.

3. Don’t wear watch & ring during work.

4. Wear Leather apron and boots

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Machine Shop Safety (Contd)

5. Never work alone

At least two workers must be in the shop when power tools are being used

6. Never work when you are impaired

This includes when you are too tired, stressed or hurried to work carefully

7. Safe conduct in the machine shop

Your conduct in the workshop should be safe and responsible and not hurtful or damaging to any worker/operator Concentrate on what you are doing and if you start getting tired, please stop and take a small break. Never try to rush tasks

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Machine Shop Safety (Contd)

8. Always wear closed toe shoes in the shop

Tools, chips and fixtures are sharp and often hot. Shoes will help protect your feet from injury. Leather shoes are preferred when machining

9. Eye protection is essential

Always wear safety glasses when working or cleaning tools

10. Remove or secure anything that might get caught in moving machinery

Rings, necklaces, wrist watches, long hair and loose clothes that get caught in tools can drag you along

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Machine Shop Safety (Contd)

11. Keep your hands away from sharp tools

Make sure that nothing that you do will cause you to be cut. Use safety gloves to handle hot or sharp objects

12. Dust, chemicals and smoke can be dangerous

Work in well ventilated areas. Minimize contamination and use appropriate protective equipment

13. Ask for guidance and help

Have shop staff check you out on a tool the first time you use one with which you are unfamiliar

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Machine Shop Safety

14. Be careful while working

If you do not know how to do some thing, ask. Before starting, study the machine and know which parts are moving, which are stationary and which are sharp and may be potentially dangerous. Listen to the machine and never leave the machine running unattended

15. Clean up after yourself

Before you leave the shop, all tools must be returned to the toolbox, the machine cleaned and wiped down and the floor swept