An objective of the mass production is to increase the productivity and the accuracy. This is done by reducing the set up cost and manual burnouts. Thus mass production can be acquired by the use of jigs.  For large scale production of unlike materials a lot of time is wasted in start of the device and clamping the device. An experimental approach method is regularly practiced until the axis of the hole is properly line up with the axis of the drill. In such a situation a division of time is being wasted to maintain the accuracy. This paper is mainly composed of design and fabrication of the Angular postjig which cover the absolute design to the described dimensions of the work piece and would make the production process easier

Deenadayalan, H.

Prabakaran, S.

Pragadeeeswaran, T.

Prakash, D.

Sivasubramanian, A.

International Journal of Research and Engineering

6 
 
 
 
IJRE | Vol. 03 No. 09 | September 2016 
ISSN 2348-7852 (Print) | ISSN 2348-7860 (Online) ijre.org 
Design and fabrication of angular post JIG 
Author(s): D. Prakash
1
, T.Pragadeeeswaran
2
, H.Deenadayalan
3
, S.Prabakaran
4
, A. Sivasubramanian
5
 
1,2,3,4
Final Year, 
5
Assistant Professor,  
Dept. of Mechanical Engineering, Saveetha School of Engineering, SaveethaUniversity-602105 Chennai 
 
ABSTRACT 
An objective of the mass production is to increase the 
productivity and the accuracy. This is done by reducing the 
set up cost and manual burnouts. Thus mass production can 
be acquired by the use of jigs.  For large scale production of 
unlike materials a lot of time is wasted in start of the device 
and clamping the device. An experimental approach method is 
regularly practiced until the axis of the hole is properly line up 
with the axis of the drill. In such a situation a division of time 
is being wasted to maintain the accuracy. This paper is mainly 
composed of design and fabrication of the Angular postjig 
which cover the absolute design to the described dimensions of 
the work piece and would make the production process easier. 
 
Keywords: Angular Jig, Holding Device, Mass Production, 
Manufacturing 
 
I.INTRODUCTION 
Mass production targets at high productivity to reduce unit 
cost and interchangeability to aideasy assembly. This make 
necessary production devices to increase the rate of 
manufacture and inspection device to advance inspection 
procedure.Jigs are special target tools which are used to aid 
production like machining, assembling and survey 
operations. The mass production of work-piece is based on 
the concept of interchange skill according to which every 
part produced inside an established tolerance. Jigs provide a 
method of manufacturing interchangeable parts since they 
establish a relation with calculated tolerances, between the 
work and the cutting tool. Once the jig is correctly set up, 
any number of identical parts may be readily produced 
without additional set up. Jigs are used on drilling, reaming, 
tapping, milling and tapping. There are many benefits for 
using jigs in production. Jigs remove individual making, 
positioning and repeated checking. This reduces operation 
time and increase productivity.  
 
II.DESIGN PROCEDURE 
The points that are taken into discussion for designing a 
product are as following:   
a) Jig must be so powerful that the deflection in the jig 
should be as limited as possible. The deflection that is 
mentioned involved the forces of cutting, clamping of 
workpiece to the machine table. The frame of the fixture 
should have enough mass to prevent vibrations while the 
machining of the job.   
b) Another important design application is the clamping 
which should be actively sufficient and require limited 
amount of effort.   
c) Arrangement of clamps should be such that they are 
conveniently available. They should also have the 
arrangement for convenient removal as well.   
d) Is waving of clamp system is provided for removal of 
workpiece the clamp should swing as far as possible for 
unclamping the device.   
e) There should also be supplying for convenient removal 
of chip. This will prevent the interference of the chip with 
the operation on the workpiece  i.e. cutting operation.   
f) The clamps and stake points which are to be adapted in 
due course of time should be preferred of same size. It will 
be better if the clamps and adaptable support points can be 
conducted from the front of the fixture.   
g) If the surface area of clamping is too many it damages 
the workpiece. This can be avoided by making the surface 
area of clamping as tiny as possible.   
h) As it is difficult to get spare parts during the activity so it 
is designed in such a way that they can be conveniently 
replaced on failure.   
i) The study of the design should be finished thoroughly 
before fabricating. It should always be make sure that the 
work is done in proper order. This will ensure zero loss of 
material. It should always be preferred that there is 
maximum operation in a single setting of the workpiece.  
j) The movement of the workpiece is restricted i.e. there is 
zero degree of freedom of the workpiece after clamping the 
workpiece. Sharp edges and redundant locators must be 
avoided. One should try to maintain at least one event 
surface.  
k) The design must obtain enough rigidity and robustness to 
prevent vibration else it may advance to undesired 
movement of the workpiece and tools.  
l) Minimum cost should be incurred while the fabrication of 
the project and the design should be as clear as possible. In 
such a way it will help even a lay man to operate the 
device. 
 
 
III.PROBLEM DEFINITION 
Drilling jigs makes possible the drilling of holes at higher 
speeds,with greater accuracy and with limited skilled 
workers then is possiblewhen the holes are laid out and 
drilled “by hand”. Also, theyproduced altering parts, 
because each parts drilled in ajigs should have the same 
hole pattern as every other part. Eventhough irregular or 
contour surface is very complicated. Due tothis reason we 
have decided to design a new jig for contour profile. 
IV.JOB PROFILE 
A given workpiece is to be drilled  with a hole range 
diameter 8mm at an angle of 45 deg. 
 
Fig.1. Dimensions of the job 
1. Outer diameter of the job = 75mm 
2. Inner diameter of the job = 50 mm 
3. Length of the job  = 42mm 
4.Required diameter of the drill = 8mm 
 
7 
 
 
 
IJRE | Vol. 03 No. 09 | September 2016 
ISSN 2348-7852 (Print) | ISSN 2348-7860 (Online) ijre.org 
V. SELECTION OF BUSH 
Press fit is preferred, therefore chosen fixed bush with hole 
range diameter 8 mm. 
Generally the outside diameter of the bush will be press fit 
or push fit and inner holebush will be running fit. 
Chose bush of fixed type DDB; 5.100 
The diameter to be drill the work piece is = 8mm 
As per design standards bush sizes (long) are 
L1 = 20 mm 
L2 = 16mm 
D3 = 20mm 
 In this project bush dimensions are 
L1 = 32mm 
L2 = 20mm 
D3 = 25mm 
 
VI. SELECTION OF JIG BODY 
Thickness of frame (t) = 20mm 
Base length = 3 x length of work piece = 3x42 = 126mm 
But in this project base length is designed = 102mm 
Working height (h2) – 2 x outer diameter of work piece = 
2x 75 = 150mm 
But in this project working height = 107mm 
Total height of jig (ht) = 2t + h2 + bush head = (2 x 20) + 
150 +12 = 202mm 
But in this project Total height = 159mm 
 
VII. DESIGN FOR SCREW ROD 
Size of the screw (Bolt) = M24 
Pitch = 3mm (from5.42) 
For coarse thread dc = 0.84 x d = 0.84 x 24 
Dc = 20.14 mm 
Stress area = 353 mm
2 
 
Initial tension in bold p1 = 280 x d  
                                         = 2860x 24  
                                          = 68460 N 
But this p1 = (π/4) x dc2 x ft 
                    = 214.885n/mm
2 
 
ft =  214.885n/mm
2
 
As the pin is double shear 
P1 = 2 x (π/4) x dc2 x ft 
ft = 68640/( 2 x (π/4) x 20.142 ) 
   = 107.730 N/mm
2 
 
Shear stress as the pin is double shear 
Fs = p/(π x dc x b x n) 
Shear stress = Load / area  
      = 68640/ (π x 20.14 x 1.5 x 10) 
                    = 72.133N/mm
2  
107.730>72.133 
Therefore our design is safe  
 
VIII. SELECTION OF LOCATING PIN 
For side location, pin locater is to be assembled to the work 
piece. Locater diameter is 24 mm that is to be shoulder the 
inner diameter work piece. 
Locater height = 80mm 
 
IX. DIMENSION OF THE JIG COMPONENTS 
1.  Length and width of  base plate of the jig   = 102 x 
145 mm 
2. Thickness of the plates= 20 mm 
3. Vertical jig plate length & width  =  107 x 150mm 
4. Top jig plate length & width = 79 x 65mm 
5. Angular post plate = 117 x 63mm 
6. Locater  diameter = 24.5mm 
 
Fig.2. Design of  Angular Post Jig 
X.ADVANTAGES 
 It eliminates the individual marking; positioning 
and repeatedchecking. 
 The operation time is shortened due to increase in 
speed,feed and depth of cut because of huge 
clamping rigidity. 
 
 It is verymuch valuable in mass production.It 
makes possible to manipulate unskilledor semi- 
skilled operator to make savings in labour cost. 
 It fractionally automates the tools. 
 It reduces the expenditures onquality control of 
machine parts. 
 
XI. LIMITATIONS 
It is only used for small-scale  components. It is only used 
for the hollow cylindrical work piece. Forces causing 
deflection may arrive from handling.There is no special 
way to unload the chips produced by drilling.So it requires 
separate time. 
 
XII. CONCLUSION AND FUTURE SCOPE 
This paper deals with the design and fabrication of Angular 
post jig and the detailed drawing of the component and 
assemblies. It is very useful to industries for mass 
production of identical parts. In future it may used for 
special purposes shaping to suit the profile of the 
component and to minimize weight by use of thinner 
section thus makes the advantage of economy of time. The 
special drill bushes can be used if hole being drilled is in 
recess and thus preferred for accurate work when light 
work piece to be drilled. 
REFERENCE 
[1]R.S.Khurmi “Design of Machine Elements”, Eurasnia 
publishing house 3 Pvt Ltd, 14th revised edition.  
[2] Kempster, "Introduction to Tool Design and Jigs and 
Fixtures", ELBS  
[3] ASTME, “Hand book of Fixture design”[4] 
Dr.V.Jayakumar “Design of TransmissionSystems”, 
Lakshmi Publications Pvt Ltd, 4th revised edition. PSG 
College of Technology “Design data Book”, PSG College 
Publishment,latest 2011 revised edition. 
[5] https://en.wikipedia.org/wiki/Jig_(tool) 
[6] http://accessengineeringlibrary.com/browse/jigs-and-
fixtures-third-edition. 
  


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