MECH152-L25 - 1

Tool Design

MECH152-L25 - 2

Types of Tools• Material Cutting Tools• Workholding Devices• Pressworking Tools• Bending, Forming and Drawing Dies• Tool Design for Inspection and Gaging• Tool Design for Joining Process• Tooling for Castinghttp://www.youtube.com/watch?v=3ciyG_hidhE&feature=channel_page

http://www.youtube.com/watch?v=4Pw_tcgIiTQ&feature=channel_page

http://www.youtube.com/watch?v=z4D76vMqwD4&feature=channel_page

http://www.youtube.com/watch?v=gkHbRVUvFgw&feature=channel_page

MECH152-L25 - 3

General Considerations• Safety and Ergonomics• Tool Materials• Heat Treatment• Surface Roughness and Finish• Tolerances and Fits• Tooling Economics• Material Handling

MECH152-L25 - 4

Safety and Ergonomics (I)• Safety should be built into the design

with due respect to legal requirements• Sufficient clamping and rigidity of the

tool design is necessary• Guards should be introduced to

movable parts of the machine• Limit switches to protect workers and

product against moving parts• Electrical equipment should be properly

grounded

MECH152-L25 - 5

Safety and Ergonomics (II)• Exhaust system for air polluting system• All adjustments and clamping should be

easily accessible• Quick release or emergency braking

mechanism may be needed for special cases

• Prevent severe burns or eye injury for welding or thermal process

• Provision for handling pressurized and toxic equipment

MECH152-L25 - 6

Tool Materials (I)• Tool steels (principal materials)

– Tool and Die Steel (typical hardness RC40~60)• W, Water-Hardening Tool-Steels• O, Oil-Hardening Tool-Steels• A, Air-Hardening Medium Alloy Die-Steels• D, High-Carbon High-Chromium Die Steels• S, Shock-Resisting Tool-Steels• H, Hot-Work Die Steels• P, Low-Carbon Mold Steels• T and M, Tungsten and Molydenum High-Speed Steels• L, Low-Alloy Tool-Steels• F, Carbon-Tungsten Finishing Steels

(http://www.efunda.com/materials/alloys/tool_steels/tool.cfm)

• Cast Iron• Stainless Steel

MECH152-L25 - 7

Tool Materials (II)• Non-ferrous materials - limited

productions only (Aluminum, Magnesium, Zinc, Lead, Beryllium, Bismuth)

• Composite materials – soft tools for limited run

MECH152-L25 - 8

Workholding DevicesWorkholding Devices – All devices that

hold, grip, or chuck a workpiece in a prescribed manner of firmness and location, to perform on it a manufacturing operation.

MECH152-L25 - 9

Fixture & JigFixture:

- Hold and accurately position a workpiece

Jig:- Also be used to hold and position a workpiece.- Provides some means for guiding the cutting tool

http://www.youtube.com/watch?v=ujKyRrf-Z1M&feature=channel_page

http://www.youtube.com/watch?v=2ikkuZe0zQU&feature=channel_page

MECH152-L25 - 10

Examples - I• High Rise Clamps http://www.carrlane.com/Catalog/index.cfm

High-Rise Clamps can be stacked on Narrow Riser Blocks and Spacer Blocks to reach tall workpieces

MECH152-L25 - 11

Examples II• Swing Clamp

ARM: MODULAR IRON PER ASTM A536 GRADE 65-45-12, ZINC PLATED CLEAR CHROMATE

ALL OTHER PARTS: MILD STEEL, BLACK OXIDE FINISH

Please refer to the price list also!

http://www.steelsmith.com/

MECH152-L25 - 12

Examples IIIAutomatic Reversible Cam Action Workholding Assemblies

http://www.youtube.com/watch?v=vrrjLYn-6WY

MECH152-L25 - 13Methods of Location3-2-1 Principle

- A workpiece will be completely confined when banked against:- 3 points in one plane- 2 points in another plane- 1 point in a third plane- If the planes are perpendicular to each

other- Buttons should be as far apart as

possible- Greater spread, Less alignment error

http://www.youtube.com/watch?v=wTs_IaD0JWU&feature=PlayList&p=3AFB507B668AF162&index=35

MECH152-L25 - 14

Methods of Location I

12 degrees of freedom

3 pins arrest 5 dof

MECH152-L25 - 15

Methods of Location II

6 pins arrest 9 dof

5 pins arrest 8 dof

Vertical workpiece

Horizontal workpiece

MECH152-L25 - 16

Methods of Location IIIRadical location with internal pins or plug

Radical location by external pins

MECH152-L25 - 17

Methods of Location IV

7 dof arrested by V locator with stop pin

Workholder with multiple V locators

MECH152-L25 - 18

Tool Forces I

Pin-type drill fixture resisting torque and thrust

Tapping fixture resisting torque and thrust

MECH152-L25 - 19

Tool Forces IIWorkholder for broaching operation

Cutting Forces resisted by solid jaw of vise

Cutting force resisted only by friction

MECH152-L25 - 20

Tool Forces IIIMechanical methods of transmitting and multiplying force

(A) Screw

(B) Cam

(C) Wedge

(D) Toggle link

(E) Lever

(F) Combined screw and wedge

MECH152-L25 - 21

Clamping Forces I

Fixture components

MECH152-L25 - 22

Clamping and Support

Clamping and support of large workpiece

http://www.youtube.com/watch?v=l-V4mplHjZ8

MECH152-L25 - 23

Fixture Components

MECH152-L25 - 24

Fixture Components

Toggle clamp

Quick-acting screw

http://www.youtube.com/watch?v=H4r8hUyZMUY

http://www.youtube.com/watch?v=nheuik2YHkIhttp://www.youtube.com/watch?v=ZefYGTMKRUw

MECH152-L25 - 25Jigs and Fixture Design Principles

• Review the workpiece to determine the manufacturing processes

• Decide on the number of setups• Determine for each setup

– Reference surface– Workpiece location– Workpiece clamping and rigidity– Ergonomics and safety

http://www.youtube.com/watch?v=ujKyRrf-Z1M&feature=channel

MECH152-L25 - 26Fixture for Rectangular Components

• Location and holding for flat surface• Base plate - reference surface for setup• Clamp – quick action cam-based clamp

Clamping action

MECH152-L25 - 27Fixture for Rectangular Components

• Hydraulic clamp for larger clamping force• Swing clamp http://www.youtube.com/watch?v=1RMqoQlZ-2c

http://www.youtube.com/watch?v=jkAINXgZaCk

MECH152-L25 - 28Fixture for Rectangular Components

Magnetic chuck

Vacuum chuck

http://www.youtube.com/watch?v=2jcQZ5W4ED4

http://www.youtube.com/watch?v=xr3lfAvQuJs&feature=related

http://www.youtube.com/watch?v=WzawhEUBLL8&feature=PlayList&p=CAC636741CCDCCB0&playnext=1&playnext_from=PL&index=4

http://www.youtube.com/watch?v=S-xKCAHpU-4&feature=PlayList&p=CAC636741CCDCCB0&playnext=1&playnext_from=PL&index=6

http://www.youtube.com/watch?v=8pabjZp4D2Y

MECH152-L25 - 29Fixture for Rectangular Components

Vacuum chuck

Electrostatic chuck

MECH152-L25 - 30Fixture for Circular Components

Round workpiece held with strap clamp and T bolts

Fixture for straddle milling connecting rod

MECH152-L25 - 31Fixture for Circular Components

Workpiece held in a 4-jaw chuck for a boring operation

Nut arbor

http://www.youtube.com/watch?v=npJfKhkS0QE

MECH152-L25 - 32Fixture for Circular Components

V block

Drill jig – V block, quick-acting clamp, and drill bushing combination

http://www.youtube.com/watch?v=QFH2kUorn88

MECH152-L25 - 33Fixture for Circular Components

Internal and endwise chucking

Between centers and combination with chucking

MECH152-L25 - 34Fixture for Circular Components

Solid mandrel Roll lock type expanding mandrel

MECH152-L25 - 35Fixture for Circular Components

Split busing and split collet

Axial location by collet

Collet with stopper

http://www.youtube.com/watch?v=bJIIeN4rg3E

MECH152-L25 - 36Fixture for Circular Components

Collet with immediate bushing to eliminate axial shift

Collet for internal chucking

MECH152-L25 - 37

Rigid and Elastic Workholding

Elastic and spring workholding

Rigid workholding

Rigid/hydraulic workholding

MECH152-L25 - 38

Accuracy of Work Location

Accuracy of work location Concentricity of workpiece by collet

MECH152-L25 - 39Workholders for Irregular Workpiece

Pump-type jigs

MECH152-L25 - 40

Workholding Selection

Workpiece rotation Tool rotation

MECH152-L25 - 41

Workholding Selection

Minimizing cutting force by applying holding force close to point of tool application

Steady to reduce workpiece vibration

http://www.youtube.com/watch?v=2o74aR0JL1k

MECH152-L25 - 42

Cutter Setup

MECH152-L25 - 43

Box-Type Drill Jigs

MECH152-L25 - 44

Milling Fixture

MECH152-L25 - 45

Milling Fixture

MECH152-L25 - 46

Milling Fixture

Indexing fixture

Key slot millinghttp://www.youtube.com/watch?v=JkftVHaMQSs

MECH152-L25 - 47

Milling Fixture