Performing Bench Work (Basic)

DLM 03 Developing print-based Learner’s Guide including all related documents
Notes Format of Learner’s Guide

Course: Machining NC 2
Unit of competency: Perform Bench Work (Basic)

Module: Perform Bench Work (Basic)

Learning outcomes: At the end of the session, learners should be able to:
1. Determine Job Requirements
2. Prepare Work Area
3. Perform Bench work Operation
4. Check and Measure Work piece

Duration: 56 hrs.

Situating Learning: You are a machinist in a machine shop. One day a problem occurs in
the shop tool room. There are no more tap holders available. And all
machines are being used in fabrication of rush jobs.

Your supervisor assigned you to fabricate tap holders in the bench
area to do some bench work since no machines are available except
a small drill press and a bench grinder. In order to complete the task,
you need a layout of the work piece, prepare the necessary tools and
equipment then plan the bench work operations needed to perform
the job.

You need to fabricate 5 tap holders for your fellow machinist who will
be using it in their fabrication of an immediate job. In order to check
the accuracy of your work your supervisor will check the following:

1. Procedures are correct.
2. Surfaces are square, smooth and free of burrs.
3. All parts are properly fitted together.
4. Work measurements should meet the tolerance given in the

drawing.
5. Mating threads fits properly.

Assessment Criteria: 1. Laid-out and marked dimensions/features on the work piece
2. Cut, chipped and filed work piece.
3. Drilled, reamed and lapped holes.
4. Cut threads
5. Performed off-hand grinding

Pedagogical Training in Instructional Design & Delivery for TVET Page 1
© 2010, Institute of Technical Education, Singapore

DLM 03 Developing print-based Learner’s Guide including all related documents
Notes Format of Learner’s Guide

Learning chunk Performance Criteria Learning Activities Learning documents
(Brief description of (Documents
strategies, sequence
of lesson, evaluation) referenced by each
learning activity)

1. Perform Bench  Work pieces are 1.1 Identify types of  Read Information
work Operations clamped in work
holding devices to clamps and vise. Sheet 1.1.1 -
Clamp and hold avoid damage and
work piece accidents Work Holding

1.2 Determine the Devices

correct work

holding device for a  Answer Work

particular type of Sheet 1.2.1

work. questions

2. Perform Bench  Work pieces are 2.1 Identify types of  Read Information
work Operations Sheet 2.1.1 –
cut to within hacksaw blade Hacksaw and
Perform Sawing sawing
Operation tolerance specified
 Follow procedures
in the drawing. 2.2 Select hacksaw on Operation
Sheet 2.2.1
blade.

 Broken or dull 2.3 Install hacksaw
hacksaw blades blade.
are replaced

according to 2.4 Prepare work for
requirements sawing

 Bench work

operations are 2.5 Select Sawing

performed applying Techniques.

knowledge on

safety procedures

and using personal

protective devices.

3. Perform Bench  Work pieces are 3.1 Identify types of  Read Information
work Operations Sheet 3.1.1 –
cut, chipped or filed Chisels Chisel and
Perform Chipping Chipping
Operation to within tolerance 3.2 Describe the
specified in the application of the  Follow procedures
drawing. different types of on Operation
Sheet 3.2.1
 Bench work chisels.

operations are
performed applying 3.3 Chipped work to

knowledge on size.

safety procedures

and using personal

protective devices.

4. Perform Bench  Work pieces are 4.1 Identify the different  Read Information
work Operations
cut, chipped or filed classification of files. Sheet 4.1.1 –

to within tolerance Files and Filing.

Pedagogical Training in Instructional Design & Delivery for TVET Page 2
© 2010, Institute of Technical Education, Singapore

DLM 03 Developing print-based Learner’s Guide including all related documents
Notes Format of Learner’s Guide

Learning chunk Performance Criteria Learning Activities Learning documents
(Brief description of (Documents
Perform Filing specified in the strategies, sequence
Operation drawing. of lesson, evaluation) referenced by each
learning activity)
 Bench work 4.2 Describe the
operations are application of the  Answer Work
performed applying different types of Sheet 4.2.1
knowledge on files. questions
safety procedures
and using personal 4.3 Identify the different  Follow procedures
protective devices. filling techniques. on Operation
Sheet 4.3.1
4.4 Select filling
methods.

4.5 Sequences filling
methods.

5. Perform Bench  Materials are 5.1 Identify the different  Read Information
work Operations Sheet 5.1.1 –
Perform Lay outing selected according layout tools. Layout tools
and Marking of
Work to the requirements 5.2 Describe the  Read Information
specified in the application of the Sheet 5.2.1 –
drawing. different types of Layout tools

 Dimensions/feature layout tools.  Answer Work
Sheet 5.3.1
s are laid out and 5.3 Identify the different
marked in lay-outing  Follow procedures
accordance with techniques. on Operation
drawing Sheet 5.4.1

specifications using
bench work tools 5.4 Sequences lay
outing techniques.
and equipment.

 Lay outing and
marking are
performed applying
knowledge on
safety procedures
and using personal
protective devices.

6. Perform Bench  Hole is drilled, 6.1 Identify the different  Read Information
work Operations Sheet 6.1.1 –
Drill, ream, bore reamed, spot-faced types of drilling Drilling machine
and counter bore, and accessories
spot face holes. and lapped to machine.
 Answer Work
drawing 6.2 Describe the
specification. application of the

 Drilling, reaming or different types of Sheet 6.2.1

lapping holes are drilling machine.

performed  Follow procedures

according to 6.3 Describe the on Operation

recommended application of the Sheet 6.3.1

sequence. different types of drill

bit.

 Operations are 6.4 Identify the different

Pedagogical Training in Instructional Design & Delivery for TVET Page 3
© 2010, Institute of Technical Education, Singapore

DLM 03 Developing print-based Learner’s Guide including all related documents
Notes Format of Learner’s Guide

Learning chunk Performance Criteria Learning Activities Learning documents
(Brief description of (Documents
performed applying strategies, sequence
knowledge on of lesson, evaluation) referenced by each
safety procedures learning activity)
and using personal types of work
protective devices holding device.

6.5 Lay out work to be
drilled according to
requirements.

6.6 Set up work piece.

6.7 Sequences drilling
operation.

7. Perform Bench  Thread is cut to fit 7.1 Identify the different  Read Information
work Operations gage or mating types of threads. Sheet 7.1.1 –
Cut threads using screw, within Screw Threads
taps and dies. tolerance given in 7.2 Describe the
the blueprint application of the  Answer Work
different types of Sheet 7.2.1
 Thread is cut in threads.
accordance with  Follow procedures
the recommended 7.3 Identify the parts of on Operation
tapping sequence a screw threads Sheet 7.3.1

 Thread cutting

operations are 7.4 Determine the TDS
performed applying for a specific pitch of
knowledge on thread.
safety procedures

and using personal
protective devices. 7.5 Identify the different

types of taps and

dies.

7.6 Determine the types
of taps and dies to
be used.

7.7 Describe procedure
in cutting threads
using taps and dies.

8. Perform Bench  Cut edges are 8.1 Identify the different  Read Information
work Operations Sheet 8.1.1 –
Off-hand grind honed and free of types of Off-hand Grinding
cutting tools.
burrs. grinders.  Answer Work
Sheet 8.2.1
 Cutter is sharpened
 Follow procedures
to conform to 8.2 Describe the on Operation
Sheet 8.3.1 – Tool
specifications. application of the Grinding

 Cutters are ground different types of

using appropriate grinders.

cooling agents.

 Cutting tool 8.3 Describe the

grinding is application of the

performed applying different types of

knowledge on grinding wheels.

Pedagogical Training in Instructional Design & Delivery for TVET Page 4
© 2010, Institute of Technical Education, Singapore

DLM 03 Developing print-based Learner’s Guide including all related documents
Notes Format of Learner’s Guide

Learning chunk Performance Criteria Learning Activities Learning documents
(Brief description of (Documents
safety procedures strategies, sequence
and using personal of lesson, evaluation) referenced by each
protective devices. learning activity)
8.4 Describe the
procedure in
grinding cutting
tools.

9. Determine Job  Components, 9.1 Identify components,  Answer Work
Requirements
assemblies or assemblies or Sheet 9.1.1
 Interpret plans/
drawing objects recognized objects required.

as required.  Answer Work

 Dimensions 9.2 Identify dimensions Sheet 9.2.1

 Determine identified as 9.3 Identify the materials
needed
sequence of appropriate.
9.4 Identify symbols
operation  Instructions
9.5 Identify limits and
 Identify the identified and fits.

different types work followed as

holding devices required.

needed.  Material

requirements

identified as 9.6 Identify instructions
required.

 Symbols

recognized as

appropriate in the

drawing.

 Tolerance, limits

and fits identified in

the drawing

10. Prepare work area  Work area is 10.1 Identify needed  Read Information
Sheet 10.1.1 –
prepared according tools and Shop Safety

to workplace equipment  Read Information
Sheet 11.1.1 –
requirements . Different types of
measuring tools.
10.2 Practice Shop
 Answer Work
Safety Sheet 11.1.2
questions
11. Check and  Measuring tools 11.1 Select and use
Measure Work are selected and measuring tools
piece
used according to 11.2 Clean and store
the level of measuring tools
accuracy required.

 Measurements

taken are accurate

to the finest

graduation of the

selected measuring

instrument.

 Measuring

technique used is

Pedagogical Training in Instructional Design & Delivery for TVET Page 5
© 2010, Institute of Technical Education, Singapore

DLM 03 Developing print-based Learner’s Guide including all related documents
Notes Format of Learner’s Guide

Learning chunk Performance Criteria Learning Activities Learning documents
(Brief description of (Documents
correct and strategies, sequence
appropriate to the of lesson, evaluation) referenced by each
device used. learning activity)

Pedagogical Training in Instructional Design & Delivery for TVET Page 6
© 2010, Institute of Technical Education, Singapore

Information Sheet 1.1.1: Work Holding Devices

Learning outcomes:
1. Work pieces are clamped in work holding devices to avoid damage and accidents
Learning Activity:
1.1 Identify types of clamps and vise.
1.2 Determine the correct work holding device for a particular type of work.

Many devices have been designed to hold work securely while it is being measured or
machined. Some of them are for one specific piece of work; others are of a more general
nature. These include many types of clamps and vices.

Clamps

A clamp is a fastening device to hold or secure objects tightly together to prevent
movement or separation through the application of inward pressure. There are many
types of clamps available for many different purposes.

Types of Clamps

C-Clamp Fig. 1.1
Fig. 1.2
A C-clamp is an all- purpose clamp, made in the shape of
the letter C (figure 1.1). In general use for all kinds of work, It
is made in many sizes. C-clamps are also commonly used in
welding. The heavy duty metal construction and the curved
shape make it ideal for holding together metal pieces that
need to be welded together.

Tool makers clamp
A tool maker’s clamp has two parallel jaws, which may be
adjusted to fit a piece of work by means of a screw passing
through the center of each jaw. Another screw in the end of
one jaw is used to exert pressure on the other jaws. It is
used by toolmakers for holding small parts both at the bench
and at machines. (figure 1.2)

Quick Action Bar Clamp Fig. 1.3

Quick action bar clamps are an adaptation of the “G” clamp Date: Revised Page #
and are widely used in the workshop and also for on-site 1
installation work. Another name for this clamp is “friction
clamp” because the self-locking arm can be quickly adjusted
by sliding the adjustable jaw along the toothed bar. (figure
1.3)

Code No. Perform Bench Work (Basic) Date: Developed
MEE722301 April 2010

Information Sheet 1.1.1: Work Holding Devices

Sash Clamps Fig. 1.4
Sash clamps are used in the manufacture and/ or repair of
large items. The jaws are called shoes and both are
adjustable. (figure 1.4)

Hand Spring Clamp
These simple hand spring clamps have two flat jaws which
are forced together by a strong spring. (figure 1.5)

Fig. 1.5

Using Clamps

 Clamps are intended to fasten a work piece directly to the table or to an angle plate, Vee
block or fixture attached to the table.

In whatever way a work piece is clamped to the table, care must be taken to ensure that
the work piece is not sprung or distorted by applying excessive or unbalanced force.

 Choose the right size clamp for the work involved to avoid overloading a clamp that is too
small.

 Clamps are designed for temporary holding, so always remove them as soon as the job is
finished.

 When storing clamps, always keep them hanging in racks when not in use, never in laying
in a drawer.

 Before using a web clamp, be sure to inspect it for fraying or cuts before applying
pressure. And discard the tool if any frays or cuts are found.

 Use spring clamps only where moderate pressure is required.

 Discard any clamp if its frame, screw or spindle is bent.

 Do not use a wrench, pipe, hammer or pliers to tightening a clamp. A wrench should be
used only on clamps designed to be tightened with a wrench.

 Never use a C-clamp for lifting anything.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 2

Information Sheet 1.1.1: Work Holding Devices

Vise

These are devices consisting of two parallel jaws for holding a work piece. One of the jaws is
fixed, and the other can be moved by a screw, lever, or cam. Vises used for holding a work
piece during hand operations (such as filing, hammering, or sawing) are usually permanently
bolted to a bench. In vises designed to hold metallic Work pieces, the faces of the jaws are
hardened steel plates, often removable, with teeth that grip the work piece. Woodworking vises
have smooth jaws, often of wood, and rely on friction alone rather than on teeth.

Types of Vise

Bench Vise
A bench vise is usually swivel- based is the most favored for
general shop work. It is securely fastened to the bench with
the bolts. The faces of jaws are usually lightly serrated and
hardened to ensure a firm grip on the work. The width of the
jaws and the max opening between them determine the size
of the vice. (figure 1.6)

Fig. 1.6

Hand Vise

A small vise held in the hand in doing small work. It is used
by toolmakers at the bench for small machining operations
such as drilling or tapping. (figure 1.7)

Fig. 1.7

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 3

Information Sheet 1.1.1: Work Holding Devices

Pipe Vise
Pipe vise are use to hold round work such as pipes, tubing and round bars. They have a Vee
shape serrated jaws that’s holds the round work in place. (figure 1.8)

Fig. 1.8 Cutting pipe with a
pipe vise
Using a Vise
 Position the work properly. (figure 1.9)

 Tighten the vise lightly. (figure 1.10) Fig. 1.9
Fig. 1.10

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 4

Information Sheet 1.1.1: Work Holding Devices
 Never use a hammer to tighten or loosen the vise, the weight of the body is sufficient.
 Always use a vise big enough for the parts or type of work to be held.
 When round parts must be held, soft metals or hard wood jaws can be used to prevent

slipping or damage to parts. Whenever finished surfaces must be held, be sure to use soft
metal jaw covers to prevent marring the finish.
 Some jaws of a vise can be replaced when needed. Soft metal jaw caps usually are made
of soft metals such as lead copper and plastic (figure 1.11)

Fig. 1.11

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 5

Worksheet 1.2.1: Work Holding Device

Learning outcomes:
1. Work pieces are clamped in work holding devices to avoid damage and accidents.
Learning Activity:
2.1 Identify types of clamps and vise.
2.2 Determine the correct work holding device for a particular type of work.

Encircle the letter of the correct answer.

1. A fastening device to hold or secure objects tightly together to prevent movement or

separation through the application of inward pressure. There are many types of clamps

available for many different purposes.

a. Clamp c. C Clamp

b. Vise d. Bench Vise

2. An all- purpose clamp, made in the shape of the letter C. In general use for all kinds of

work, It is made in many sizes and are also commonly used in welding.

a. Quick action bar clamp c. C Clamp

b. Tool makers clamp d. Hand spring clamp

3. These clamps are adaptation of the “G” clamp and are widely used in the workshop and

also for on-site installation work. They have a self-locking arm that can be quickly adjusted

by sliding the adjustable jaw along the toothed bar.

a. Quick action bar clamp c. Sash Clamp

b. Tool makers clamp d. Hand spring clamp

4. This clamp has two parallel jaws, which may be adjusted to fit a piece of work by means of

a screw passing through the center of each jaw. Another screw in the end of one jaw is

used to exert pressure on the other jaws. It is used by toolmakers for holding small parts

both at the bench and at machines.

a. Quick action bar clamp c. Sash Clamp

b. Tool makers clamp d. Tool makers clamp

5. These clamps are used in the manufacture and/ or repair of large items. The jaws are

called shoes and both are adjustable.

a. Quick action bar clamp c. Sash Clamp

b. Tool makers clamp d. Hand spring clamp

Code No. Work Holding Devices Date: Developed Date: Revised Page #
ALT723307
April 2010 1

Worksheet 1.2.1: Work Holding Device

6. These clamps have two flat jaws which are forced together by a strong spring.

a. Quick action bar clamp c. Sash Clamp

b. Tool makers clamp d. Hand spring clamp

7. This work holding device has two parallel jaws for holding a work piece. One of the jaws is

fixed, and the other can be moved by a screw, lever, or cam.

a. Clamp c. C Clamp

b. Vise d. Bench Vise

8. This are use to hold round work such as pipes, tubing and round bars. This working
devises have a Vee shape serrated jaws that’s holds the round work in place.

a. Clamps c. Pipe Vise

b. Hand Vise d. Bench Vise

9. This vise usually has a swivel- base and is the most favored for general shop work. It is

securely fastened to the bench with the bolts. The faces of jaws are usually lightly serrated

and hardened to ensure a firm grip on the work. The width of the jaws and the max opening

between them determine the size of the vice.

a. Clamps c. Pipe Vise

b. Hand Vise d. Bench Vise

10. A small vise held in the hand in doing small work. It is used by toolmakers at the bench for

small machining operations such as drilling or tapping.

a. Clamps c. Pipe Vise

b. Hand Vise d. Bench Vise

Code No. Work Holding Devices Date: Developed Date: Revised Page #
ALT723307
April 2010 2

Information Sheet 2.1.1: Hacksaw

Learning outcomes:
1. Work pieces are cut within tolerance specified in the drawing.
2. Broken or dull hacksaw blades are replaced according to requirements
3. Bench work operations are performed applying knowledge on safety procedures and using

personal protective devices.
Learning Activity:
2.1 Identify types of hacksaw blade
2.2 Select hacksaw blade.

The hand hacksaw is a basic tool in almost every toolbox. It is used mostly for cutting small
pieces of unhardened metals that cannot be cut in a more efficient way.

The Hacksaw Frame

A hacksaw frame is used along with a blade to cut metals of different sections, and is specified
by the type and maximum length of the blade that can be fixed.

Parts of a Hacksaw Frame

Frame Frame Hole
A Adjustment Holes Pin
Thread

Wing Nut

Hacksaw Blade Handle A Knurled

BC Adjustment Pin

Square Pin Frame Hole

C

Thread Pin Assembly B

Square

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 1

Information Sheet 2.1.1: Hacksaw
Types of Hacksaw Frame

 Solid Frame - Only a blade of a particular standard length can be fitted to this frame.
(figure 2.1)

Solid Frame fig.2.1

 Adjustable Frame - This is the most common used type. It gives better grip and
controls, while sawing. (figure 2.2)

Fig.2.2 Adjusting the frame

Hacksaw Blade

A hacksaw blade is made of either low alloy steel (LA) or high-speed steel (HS), and is
available in standard lengths of 250 mm and 300 mm. (figure 2.3)

Fig.2.3

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 2

Information Sheet 2.1.1: Hacksaw

Types of Hacksaw Blades

 All-hard blade
The full length of the blade between the pins is hardened and it is used for harder
metals such as tool steel, die steel and HCS (High Carbon Steel).

 Flexible blade
Only the teeth are hardened. Because of their flexibility these blades are useful for
cutting along curved lines. Flexible blades should be lighter than all-hard blades.

Blade Material

 Low Tungsten Steel
Used for general purpose sawing of mild steel copper, brass, aluminum and similar
metals.

Types
 Flexible type- Hardened on the cutting edge only, not easily broken. Used for work

cannot be held firmly.
 Hard type- Hardened throughout, can shatter if incorrectly used.

 High Speed Steel
Has fast-cutting action. They are used for sawing alloy steels, and other hard metals.

Types
 Flexible type- Hardened only on the cutting edge.
 Hard type -Best for skilled users in rigid and accurate sawing.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 3

Information Sheet 2.1.1: Hacksaw Fig.2.4

Blade Pitch

The pitch of a saw blade is the distance from a point on one
saw tooth to the same point on a neighboring tooth (figure
2.3). In SI metrics the pitch size is indicated in millimeters.
The larger the pitch number, the larger the saw teeth will be.
However, tooth size of blades in the inch system of
measurement is always given as the number of teeth per
inch

Factors in Selecting Blade Pitch (figure 2.5).

 Soft Material  Hard Material  Thin Sections

Use course pitch to give Use fine pitch to give Use finest pitch to ensure a
ample chip clearance sufficient cutting points in minimum of three
contact with work consecutive teeth in contact
at all times

Tooth Sets Fig.2.6
Kerf
Set of saw teeth refers to the way the teeth are bent to one
side or the other to provide a kerfs (the cut made by the saw)
that is wider than the thickness of the saw. The wider saw
kerf (figure 2.6) prevents the saw blade from binding by
providing clearance.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 4

Information Sheet 2.1.1: Hacksaw Fig.2.7
Fig.2.8
Types of Tooth Set

 The raker set has one tooth bent to the right, one to
the left, and one straight tooth in between; this pattern
is repeated the length of the blade. (figure 2.7)

 The wavy set has several teeth bent to the right and
several teeth bent to the left, alternately. Blades with
14 and 18 teeth [1.8 and 1.4 mm pitch] have the raker
set. Those with 24 or 32 teeth [1 and 0.8 mm pitch]
have the wavy set. (figure 2.8)

Factors Affecting the Life of Hacksaw Blades
 Choice of blade (especially the pitch)
 Manner of holding the hacksaw
 Speed of cutting
 Method of positioning and holding work
 Tensioning of the blade
 Condition of hacksaw frame

Proper Hand Sawing
 Fit the hacksaw blade into the frame correctly.
 Avoid damage to the blade.
 Hold the material for sawing securely.
 Locate the start of cut.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 5

Operation Sheet 2.2.1: Sawing

Learning outcomes:

1. Work pieces are cut within tolerance specified in the drawing.
2. Broken or dull hacksaw blades are replaced according to requirements
3. Bench work operations are performed applying knowledge on safety procedures and using

personal protective devices.

Learning Activity:

2.1 Identify types of hacksaw blade
2.2 Select hacksaw blade.
2.3 Install hacksaw blade.
2.4 Prepare work for sawing.
2.5 Select Sawing Techniques.

Sawing is the removal of small chips by means of many chisel type edges (teeth) arranged
behind one another along the narrow edge of a saw blade; a large number of these cutting
edges are effective at the same time.

Sawing mainly serves to separate materials and also to produce slits and grooves.

Sawing Techniques

Selecting the Blade

 Always use a blade suitable for the thickness of the material to be sawed. Blades are

made with 14, 18, 24 and 32 teeth per inch (5.5. 7, 9.5 and12.5 teeth per cm.)

 Select the correct pitch of the blade for cutting. Shorter the cutting section is the finer

the blade pitch. Make sure that the least four teeth are cutting at a time.

 The simplest method of selecting the proper blade is to remember that two saw teeth

should always be contacting the material when sawing.

 Harder the material the finer the blade pitch be.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 1

Operation Sheet 2.2.1: Sawing

Fit the Hacksaw Blade into the Frame Correctly

 Set frame to correct length.
 Check that both holding pins are on the same side.
 Place teeth of blade facing outward and away from the handle.
 Adjust the tension of blade sufficiently with the wing nut. A properly stretched blade will

vibrate with a clear humming sound when plucked.

 Flexible blades should be strained tighter than all hard blades.

1.

2.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 2

Operation Sheet 2.2.1: Sawing

Hold the Material for Sawing Securely

 Clamp it rigidly as close to the vice as possible.
 Clamp thin material between two pieces of wood for cutting.
 Clamp the job to be cut according to the cross section for sawing.
 As far as possible hold the job in such a way that the flat or long side can be cut rather than

the edge.

 In case the job has contour, clamp the job so that sawing can be done towards the

overhanging end.

 Clamp the job as long as possible on the vice and make sure that the marked sawing lines

is close to the side of the vice jaws in order to achieve maximum firmness.

 Tighten the jaws firmly to avoid tilting and shifting of the job.
 Whenever the section being cut shows chattering effect or vibration, the clamping needs

improvement.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 3

Operation Sheet 2.2.1: Sawing
Proper Hand Sawing
 File a notch or guideline at the starting point on smooth and hard jobs to avoid
slipping of the hacksaw.

 Apply a little downward hand force as long as only a few teeth are cutting. Press
down only during forward stroke.

 Use the full length of the blade in order to avoid early dulling of teeth in the middle
portion of the blade.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 4

Operation Sheet 2.2.1: Sawing

 Move the blade strictly in line with the marked direction. Do not tilt the frame while
sawing because bending of the blade can cause sudden breakage of the blade.

 Use sufficient pressure on the forward or cutting stroke so that the teeth actually bite
into metal. It is not necessary to lift blade from work on backstroke, but pressure
should be relieved. Always use sufficient pressure to keep blade from getting
pinched or jammed in the work as this often breaks teeth or blade.

 For efficient cutting of metal, work the blade at 40 to 50 strokes a minute. Reduce
this rate for harder metals. There is a limit to the hardness metal that can be sawed.

 Resort cutting from the opposite side in case the deviation from the marked line is
excessive.

 Slow down the cutting while completing the cut to avoid the breakage of the blade
and injury yourself.

 When cutting very thin material, such as tubing, shift the angle of the saw blade as
cutting progresses to increase the area of contact between blade and material,
allowing as many teeth as possible to contact the work at one time.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 5

Operation Sheet 2.2.1: Sawing

When the material has been cut off

 Replace the bar in the material rack.
 Remove any burrs from the blank.
 Clean the blank.
 Recheck the overall size.

Proper Care of Hacksaws

 Wipe the blade occasionally with an oily cloth to keep it from rusting. Also, keeps the
blade away from other tools to eliminate the possibility of teeth being broken or dulled.

 Normally, metal hacksaw blades are never sharpened due to the fine teeth and the
hardness of the metal. For this reason, replace them when worn.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 6

Information Sheet 3.1.1: Chisels
Learning outcomes:
1. Work pieces are cut, chipped to within tolerance specified in the drawing.
2. Bench work operations are performed applying knowledge on safety procedures and using

personal protective devices.
Learning Activity:
3.1 Identify types of Chisels
3.2 Describe the application of the different types of chisels.
3.3 Chipped work to size.
Chisels and Chipping
Chisels are tools used to cut cold metal and for these reason they are called ‘cold’ chisel, is
made from hexagon or octagon shaped tool steel, commonly called chisel steel, of a
convenient size for handling one end for the cutting operation. The other end is left blunt to
receive the blows from a hammer.

Parts of a chisel

Parts of a chisel fig.3.1

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 1

Information Sheet 3.1.1: Chisels
Cutting Angle of Chisels

• The cutting angle must suit the hardness for the metal being cut.
• The greater the angle, the less chance there is of breaking the cutting edge.

Cutting angle table fig.3.2

Common Types of Chisels
Flat Chisels
The flat chisel is the one most commonly used (fig 3.3). The cutting edge is slightly convex
(curved outward) figure 3.4. This causes the portion to receive the greatest shock, thus
protecting the weaker corners. The cutting edges angle should be 60 to 70 degrees for general
used.
They are used to remove metal from large flat surfaces and chip excess metal of weld joints
and castings.

Flat chisels fig.3.3

Flat chisels cutting edge
fig.3.3

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 2

Information Sheet 3.1.1: Chisels
Cross-cut or Cape Chisels
These are used for cutting keyways, grooves and slots. (figure 3.5)

Gross-cut chisel fig.3.5

Round Nose Chisels (figure 3.6)
They are used for cutting curved grooves that do not require square corners, mainly oil
grooves in bearings to enlarge holes and to draw over drills that begun to cut holes off centre .

Round nose chisel fig.3.6

Diamond Point Chisels
These are used for squaring materials at the corners
and for cutting V-grooves. (figure 3.7)

Diamond point chisel fig.3.7

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 3

Operation Sheet 3.2.1: Chipping

Learning outcomes:
1. Work pieces are cut, chipped to within tolerance specified in the drawing.
2. Bench work operations are performed applying knowledge on safety procedures and using

personal protective devices.

Learning Activity:
3.1 Identify types of Chisels
3.2 Describe the application of the different types of chisels.
3.3 Chipped work to size.

Before chipping observe the following:
1. Select a mushroom-free chisel and choose a hammer with a well-secured handle.
2. Wipe off oily substances, if any, from the face of the hammer.
3. Wear safety goggles.
4. Install the chip guard. (figure 3.1)

Chip guard fig.3.1

Holding the hammer fig.3.2

5. Hold the work in a vice. If necessary, support the work on a wooden block.

6. Grasp chisel in hand firmly, but loose enough so you do not absorb the shock when the
hammer strikes the chisel head (figure 3.3).

Proper holding of chisels of different sizes fig.3.3

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 1

Operation Sheet 3.2.1: Chipping
7. Position the chisel at an angle to cut the metal in uniform thickness. (figure 3.4)

Proper positioning of chisel fig.3.4

8. Hold the hammer at the end of the handle for maximum leverage. (figure 3.5) Grasp the
hammer near the end of the handle and tap head of chisel gently until you establish a
confident rhythm.

9. Hammer the head of the chisel by looking at the point of the chisel (figure 3.6).

Aiming at the point of the chisel
fig.3.6

Holding the hammer fig.3.5

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 2

Operation Sheet 3.2.1: Chipping

10. Now raise the hammer above the shoulder and strike the head of the chisel with some
force. Do this slowly until your rhythm is established. The amount of force used is
determined by the nature of the material on which you are working. The heavier the
material, the more forceful the striking should be.

11. Stop chipping before the end of the surface; otherwise the edge of the job will break off.
To prevent this, chip the end of the job from the opposite direction.

Note:
To prevent injury, the head of the chisel and the head of the hammer should be kept free of oil
or dirt at all times. In addition, watch for burring on the chisel head after extensive use
(figuren3.7). When this condition arises, have the head of the chisel reground until smooth
(figure 3.8). This will avoid cuts on the hands and will prevent metal chips from flying about.
Use goggles at all times.

Properly ground head
fig.3.12

Mushroom head fig.
3.7

IMPORTANT: When grinding a chisel, never hold it against the grinding wheel for any great
length of time. Dip it frequently in water or coolant to keep it cool. Unless this is done, heat
caused by friction with the grinding wheel will draw the temper and cause the cutting edge to
become soft and almost useless.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 3

Information Sheet 4.1.1: Files and Filling

Learning outcomes:
1. Work pieces are filed to within tolerance specified in the drawing.
2. Bench work operations are performed applying knowledge on safety procedures and using

personal protective devices.
Learning Activity:
4.1 Identify the different classification of files.
4.2 Describe the application of the different types of files.
4.3 Identify the different filling techniques.
4.4 Select filling methods.
4.5 Sequences filling methods.

Files and Filing

A File is a cutting tool made from hardened steel with many chisel-like cutting edges or teeth.
The teeth of a file removed small chips from the surface of a work piece and produce smooth,
neat and precise surfaces as well as an improved shaped and dimensional finish of the work
piece.

Parts of a File

Parts of a file fig.4.1

Classification of Files

Files are classified according to their size, shape, cuts, and grade to select the proper type of
file to use in a particular for the work.

1. Sizes of Files

The size (length) is given in inches or millimeters, and is the distance from the point to the
heel. The common file sizes are 6”, 8”, 10”, and 12” [150, 200, 250, and 300 mm].As the file
length increases, width and thickness also increase.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 1

Information Sheet 4.1.1: Files and Filling

2. Cuts of file
The teeth of a file are formed by cuts made on its face. Files have cuts of different types. Files
with different cuts have different uses.

Single Cut File Single cut fig.4.2

A single cut file has rows of teeth cut in one direction across
its face (figure 4.2). The teeth are at an angle of 60 degree
to the centerline. It can cut chips as wide as the cut of the
file. Files with this cut are useful for filing soft metal file like
brass, aluminum, bronze and copper. Single cut files do not
remove stock as fast as double cut files, but the surface
finish obtained is much smoother.

Double Cut file Double cut fig.4.3

A double cut file has two rows of teeth cut diagonal to each
other (figure 4.3). The first row teeth are known as overcut
and they are cut at an angle of 70 degree. The other cut,
made diagonal to this, is known as upcut and is at an angle
of 51 degrees. This removes stock faster than the single cut
file.

Rasp Cut File

The rasp cut has individual, sharp, pointed tooth in a line,
and is useful for filing wood, leather and other soft materials
(figure 4.4). These files are available only in half round
shape.

Rasp cut fig.4.4

Curved Cut file

These files have deeper cutting action and are useful to filing
soft materials, like- aluminum; tin, copper and plastic (figure
4.5). The curve files are available only in a flat shaper.

Code No. Perform Bench Work (Basic) Date: Developed Curve cut fig.4.5
MEE722301 April 2010
Date: Revised Page #
2

Information Sheet 4.1.1: Files and Filling
3. Grades of File

Grades of a file are the spacing of the teeth of the file.
The closer the spacing the finer the grade, the wider
the courser.

Single-cut and double-cut files are further classified
by the coarseness or spacing between the rows of
teeth.

The six kinds of spacing are: File grade fig.4.6
 Rough
 Course
 Bastard
 Second Cut
 Smooth
 Dead Smooth

Files with the widest spacing between teeth are called rough; those with the closest spacing
between teeth are known as dead smooth.

The files most often used are the bastard, second-cut, and smooth. The rough, coarse, and
dead smooth files are used only on special jobs.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 3

Information Sheet 4.1.1: Files and Filling

4. Shape of File
For filing and finishing different works, files of different shapes are used. The shape of files is
stated by its cross section.

Flat File Flat file fig.4.7

The flat file is rectangular in shape and is the most common
type of file that is use in the machine shop. It is use for
general type of work (figure 4.7).

Hand Square File Hand square file fig.4.8

The square file is square in it cross-section. It is used for
filing square holes, internal square corners, rectangular
openings, keyways and splines (figure 4.8).

Round File Round file fig.4.9
A round file is circular in its cross section. It is used for Half round file fig.4.11
enlarging the circular holes and filing profiles with fillets
(figure 4.9).

Half Round
A half round file is in the shape of a circle. It is used for filing
internal curves (figure 4.11).

Triangular File
A triangular file is of a triangular cross section. It is used for
filing corners and angles, which are more than 60 degrees
(figure 4.12).

Knife Edge file Triangular file fig.4.12

A knife-edge file has the cross section of a sharp triangle. It
is used for filling narrow grooves and angles above 10
degrees (figure 4.13).

Knife edge file fig.4.13

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 4

Information Sheet 4.1.1: Files and Filling
Proper Care of Files
Clean a file by using a file card (figure 4.14). This is a brush with short, stiff wire bristles. If
chips are left after using the file card, they should be lifted out with a pointed or flattened
cleaning wire called a “scorer” which is included as a part of most file cards.

File Card fig.4.14
To keep the file sharp, see that their surfaces are protected when not in use. Do not throw files
around on the bench or into a drawer. Keep files away from water to prevent rusting and keep
them from getting oily, as this prevents fast, clean cutting.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 5

Operation Sheet 4.2.1: Filing

Learning outcomes:
1. Work pieces are filed to within tolerance specified in the drawing.
2. Bench work operations are performed applying knowledge on safety procedures and using

personal protective devices.
Learning Activity:
4.1 Identify the different classification of files.
4.2 Describe the application of the different types of files.
4.3 Identify the different filling techniques.
4.4 Select filling methods.
4.5 Sequences filling methods.

Filing
Filing is a method of removing small amounts of material from the surface of a piece of a
metal or other hard substance. It is a work process whereby fine shavings are removed. The
surface quality of rough treated work piece is improved.

Correct Use of Files

 Before attempting to use any file, equip it with a tight-fitting handle. This eliminates to injuring your
hand.

 Normally pushed the file across the work, cutting only on the forward stroke. To prevent damage to
teeth, raise the file from the work on the return stroke.

 When using a file, apply only enough pressure to keep the file cutting.
 Never hammer on a file, or used it for prying. Do not use the file after the teeth have become

clogged until it has been properly cleaned. Learned to tap the file at the end of the stroke to clear
the teeth of chips.

When filing follow these procedures:

 Check the height of the bench vise (figure 4.1), if the height is more, use a platform and if it
less, select and use another workbench. The ideal height of a bench vise should be above
your elbow. If not you may use a pedestal to stand on to adjust your height on the vise
(figure 4.2).

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 1

Operation Sheet 4.2.1: Filing

The height of the vise should
be above your elbow

Use a pedestal stand to
increase your height on the
vise

Checking vise height fig.4.1 Pedestal fig.4.2

 Hold the job in the bench vice with a projection of 5 to 10 mm from the top of the vice jaw
(figure 4.3).

Holding a work for filing fig.4.3

 Select the files of various grades and length according to the:
a. Size of the work.
b. Quantity of the metal to be removed.
c. Material of the work.

 Check whether the handle of the file fits tightly. Hold the handle of the file and push the file
forward using your right hand palm.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 2

Operation Sheet 4.2.1: Filing

Holding the File
Most filing is done by holding the file in both hands. The file should be held in one hand only in
special or delicate work where suitable file is too small to be held in both hands.

Initial Position Initial Position Initial Position

Different ways of holding a file fig.4.4

The proper way to hold the file for heavy filing is by grasping the file handle in the right hand,
with the palm against the end of the handle and the thumb on top (figure 4.5). Cover the end of
the file with the base of the thumb of the left hand and curl the fingers under.

Holding the file for heavy filing fig. 4.5

For lighter finishing cuts the position of the right hand remains the same, but the left hand may
be changed as in the picture below (figure 4.6).

Holding the file for light or finishing cut fig. 4.6

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 3

Operation Sheet 4.2.1: Filing

Take note and the position of the body when filing Stand with the left foot pointing toward the
bench, the hollow of the right foot 8 to 12 in. from the left heel, and bend the body slightly
forward at the hips (figure 4.7).

Initial Position Final Position

Proper body position in filing fig. 4.7

Hold the tip of the file according to the quantity of the metal to be removed.

 For heavy filing
 For light filing
 For removing local unevenness

Different File Strokes

fig. 4.8 fig. 4.9 fig. 4.10

The required finish or type of job determines the cutting motion or the stroke of the file. The
cross stroke is done to recognize any unevenness on the surface of the work (figure 4.8).
Smoothing is done in most cases by a longitudinal stroke (figure 4.9). Roughing is mostly
done in transverse stroke (figure 4.10).

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 4

Operation Sheet 4.2.1: Filing

For removing the local unevenness draw filling can also be done (figure 4.11). The same
filing can also be done for fine finishing.

Draw Filing

When it becomes necessary to finish a flat surface, for
example a gasket surface, it should be draw filled. Draw
filling is done by using a single cut file and drawing the file
crosswise over the work with a light pressure (figure 4.12).
Holding the file in this manner allows it to cut when moving in
both directions

Draw filing fig. 4.11

Draw filing for finishing work fig. 4.13

Holding a file for draw filing fig. 4.12
Start filing by pushing the file uniformly during the forward stroke and release the pressure
during the return stroke.

Continue giving strokes. Balance the pressure of the file in such a way that the file always
remains flat and straight over the surface.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 5

Operation Sheet 4.2.1: Filing

Pinning of Files

 Pinning occurs when small particles of metal become embedded in the file teeth.
 It causes scratches and reduces the efficiency of the file by impairing its cutting action.
 It tends to occur when filing soft metal.
 Single cut files are less likely to pin on soft metals than the double cut files.
 Pinning may be reduced by rubbing chalk on files.
 It is best to remove pins and dirt on files by file card.
 File cards are not recommended for cleaning files with fine teeth as they are ineffective.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 6

Worksheet 4.2.1: Files and Filing

Learning outcomes:
1. Work pieces are filed to within tolerance specified in the drawing.
2. Bench work operations are performed applying knowledge on safety procedures and using

personal protective devices.

Learning Activity:
4.1 Identify the different classification of files.
4.2 Describe the application of the different types of files.
4.3 Identify the different filling techniques.
4.4 Select filling methods.
4.5 Sequences filling methods.

Write your answer on the space provided.

1. ___________________ A file with this cut has individual, sharp, pointed tooth in a line, and
is useful for filing wood, leather and other soft materials. These files are available only in
half round shape.

2. __________________ A filing method that is used for finishing work such as smoothing.

3. __________________ This are the coarseness or spacing between the rows of teeth of a
file.

4. __________________ These cuts of file have rows of teeth cut in one direction across its
face. The teeth are at an angle of 60 degree to the centerline.

5. __________________ This is a brush with short, stiff wire bristles use for cleaning files.

6. __________________ This filing stroke is done to recognize any unevenness on the
surface of the work.

7. __________________ A file shape that has a cross sections of a sharp triangle and is
used for filling narrow grooves and angles above 10 degrees of a file.

8. __________________ A filling method that is done to recognize any unevenness on the
surface of the work.

9. __________________ A file with this cut have deeper cutting action and are useful to filing
soft materials, like- aluminum, tin, copper and plastic. And are available only in a flat
shape.

10. __________________ A filling method in which the file is held on both hands for removing
any local unevenness on the work.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
ALT723307
April 2010 1

Information Sheet 5.1.1: Layout tools

Learning outcomes:
1. Work pieces are filed to within tolerance specified in the drawing.
2. Bench work operations are performed applying knowledge on safety procedures and using

personal protective devices.

Learning Activity:
5.1 Identify the different layout tools.
5.2 Describe the application of the different types of layout tools.
5.3 Identify the different lay-outing techniques.
5.4 Sequences lay outing techniques.

Layout tools
The accuracy of a layout is very important to the accuracy of the finished product. If the layout
is not correct, the work piece will not be usable. A student should therefore realize the good
layout entails the proper and careful use of all layout tools and these tools are the following:

Marking Tools
Scribers
In layout work it is necessary to scribe lines to indicate the dimensions of the work piece to be
filled or machined. Since we are dealing mostly of metal work piece it is not applicable to use
pen or a pencil in making layouts. The scriber is a tool used for this purpose. It is made of high
carbon steel and is hardened. For drawing clear and sharp lines, the point should be ground
and honed frequently for maintaining its sharpness.

fig. 5.1 fig. 5.2
fig. 5.3

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 1

Information Sheet 5.1.1: Layout tools

Marking Punches

Center punch
A Center punch is used to punch mark centers of holes that
are to be drilled, where a strong blow of hammers needed to
mark the center point (figure 5.4).

fig. 5.5

Center punch fig. 5.4

A center punch is made out of tool steel or high carbon steel, hardened tempered and ground
to an included angle of 90. The accuracy of the drilled hole depends to a certain extent by the
mark of the center punch. This will help the drill to guide in the required path.

Prick punch
Prick punches are used where the number of centerlines
intersects on a thin sheet. A prick punch is similar to the
center punch, except that the pint is much sharper; it has an
included angle of 30º to 60º (figure 5.6). They are made out
of high carbon steel, hardened, tempered and sharpened; it
has a knurled body for gripping and holding.

fig. 5.6

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 2

Information Sheet 5.1.1: Layout tools
Letter and number punches
Have you seen letters mark on some metal parts? These are marks by the letter or number
punches!
These hardened and tempered steel punches are used to stamp identifying symbols, letters or
numbers as required on the work.

Correct Usage of Punches

Proper holding of different size punch fig. 5.7
When using a punch, hold it with a steady, but rather loose grip to lessen the blow on the hand
in case of a miss. Always use a hammer proportionately large enough for the punch.

Proper Care of Punches
 The head of a punch will, in time, spread or “mushrooms” like chisels, and should be
ground down to prevent injury.
 The tip of a starting punch, pin punch and brass drift also “mushroom” or become
chewed and gouged, resulting in a rounded or uneven tip that could be potentially
dangerous. Any “mushroom” should be ground off and the tip end ground flat and
perpendicular to the centerline of the punch.
 As with chisels, care should be taken when grinding the tip of the punch. Never hit the
tip; dip it frequently in water or coolant to keep it cool

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 3

Information Sheet 5.1.1: Layout tools

Dividers
Dividers are used for scribing circles, arcs and for transferring and stepping of distances (figure
5.8).

Scribing circle fig. 5.9 Steeping of distances fig. 5.10

Divider fig. 5.8

Dividers are available with firm joints and spring joints. The measurements are set on the
dividers with a steel rule (figure 5.11).

Setting measurements fig. 5.11

For the correct location and seating of the divider legs, prick punch marks of 30 are used.

Using the dividers

 Dividers are set to a certain size by placing the divider legs on a steel rule.

 To make a circle, set the dividers to the size of the radius, half the diameter desired. To
scribe a circle: Gently hold the dividers stem.

 Place the point of one leg in the prick-punched mark at the intersection of the layout
lines.

 Then swing the other leg in a circle.

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 4

Information Sheet 5.1.1: Layout tools

Trammels
This tool is like a beam compass or divider used for drawing arcs or circle having a large
radius (figure 13).

fig. 5.13

fig. 5.14

This tool has point holders that are perpendicular to the surface being scribed, and has caliper
legs, a pencil point, or a pen point may be substituted for a divider points. A ball is also
provided to enable an arc or circle to be scribed, using a hole as a center.

Hermaphrodite Calipers
These calipers have one leg with an adjustable divider point, while the other is a bent leg
(figure 5.15). The legs are joined together to make a firm joint.

Hermaphrodite caliper fig. 5.16
fig. 5.15
fig. 5.17

These calipers are used for marking lines parallel to inside and outside edges (figure 5.16) and
for locating the center of round bars (figure 5.17).

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 5

Information Sheet 5.1.1: Layout tools

Marking Equipments

Center Square
This tool is used to find the center of a round piece of
metal (figure 5.17). To get the centerline, three lines
about 60º apart should be scribe on the work.

Center square fig. 5.18

Try Square fig. 5.19

The try square is a precision instrument which is used
to (figure 5.19):

 Check squareness (angle of 90) of a surface
 Check the flatness.
 Mark lines at 90 to the edges of work pieces

(figure 5.20).
 Set work pieces at right angles.

The accuracy of measurement by a try square is
about 0.002 mm per 10-mm length, which is accurate
enough for most workshop purpose. The try square
has a blade with parallel surfaces it may be fixed or
adjustable for length. The blade is fixed to the stock at
90. Try squares are made of hardened steel.

fig. 5.20

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 6

Information Sheet 5.1.1: Layout tools
Bench plate/ Surface plate
When accurate dimensional features are to be marked, it is essential to have a datum plane
with perfectly flat surface. Marking datum surfaces, which are not perfectly flat, will result in
dimensional error.
The most widely used datum surfaces in the machine shop work are the bench plate and
marking tables.

fig. 5.21

fig. 5.22

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 7

Information Sheet 5.1.1: Layout tools

Angle plates

Angle plates are "L" shaped pieces of cast iron or steel carefully machined to an angle of 90
(figure 5.23). They are used to hold work at right angles to a marking- out table or machine
table. The work can be securely clamped to the plate to enable marking out to be performed.
Often the work is machined while still set on the angle plate.

fig. 5.23 fig. 5.24

Vee blocks and Clamps

Vee blocks are used to hold circular work when marking out or setting up for machining. They
are manufactured in pairs from cast iron or steel. A variety of sizes are available. Some Vee
blocks are fitted with a clamp to hold work securely in position.

fig. 5.25

Code No. Perform Bench Work (Basic) Date: Developed Date: Revised Page #
MEE722301 April 2010 8