The document discusses Abhyuday Raj Sinha's four week summer training project at Tata Motors in Lucknow, India. It summarizes that the project involved analyzing paint scratches on vehicle cabs assembled at Trim Line 3 of the factory. During observations of over 100 cabs, the most common locations for paint scratches were near the door lock, on stay rods, near the upper window, and on the inside central panel. The document lists the frequency and location of observed paint scratches.

3. I hereby declare that the project work entitled PAINT SCRATCH ANALYSIS is an
authentic record of my own work carried out at TATA MOTORS, LUCKNOW as
requirements of four week summer training project, under the guidance of MR.
MANOJ MAHAJAN (Senior Manager, Trim Line-3) ,during 24TH MAY 2016 to 21ST JUNE
2016.
Dated: 21.06.2016 Abhyuday Raj Sinha
B.Tech(MAE)- 3rd Year
Amity University, Lucknow
Certified that the above statement made by the student is correct to the best of our
knowledge and belief.
Mr. Manoj Mahajan Mr. Lokesh Ahuja
Senior Manager Manager
Trim Line 3 Trim Line 3
Tata Motors, Lucknow Tata Motors, Lucknow

4. Industrial training is a crucial period in engineering curriculum since it exposes a student
to the real world which he or she is going to enter after the completion of the
graduation. This is the period during which an engineer actually becomes an engineer by
gaining the Industrial experience. I am very thankful to God who has given me the
opportunity to get training in TATA MOTORS, LUCKNOW, one among the most renowned
organizations of India. I would like to express my deep gratitude to my Project Head MR.
MANOJ MAHAJAN (Trim Line-3) and MR. LOKESH AHUJA(TRIM LINE-3) for having
provided me with the wonderful & conductive environment to work in and realize what
really industry is. They have always been helpful and supportive. I would also like to
thank Mr. Prabhakar Gund, Mr. Rohit, Mr. Rajiv Mishra, Mr. Naved Anwar and Mr. Ravi
Shankar for helping me throughout my training. I will always remain indebted to them
for their generous ways of dealing with Summer trainees.
Abhyuday Raj Sinha
B.Tech(MAE)
6th Semester
Amity University, Lucknow

5. Tata Motors Limited is India’s largest automobile company, with consolidated revenues of
Rs.2.625 Trillion(USD 42 billion) in 2014-15. It is the leader in commercial vehicles in each
segment, and among the top three in passenger vehicles with winning products in the compact,
midsize car and utility vehicle segments. The company is the world's fourth largest truck
manufacturer, and the world's third largest bus manufacturer.
Tata Motors helps its employees realize their potential through innovative HR practices. The
company's goal is to empower and provide employees with dynamic career paths in congruence
with corporate objectives. All-round potential development and performance improvement is
ensured by regular in-house and external training. The company has won several awards
recognizing its training programs.
Established in 1945, Tata Motors is India's largest and only fully integrated automobile company.
Tata Motors began manufacturing commercial vehicles in 1954 with a 15-year collaboration
agreement with Daimler Benz of Germany. Since 1969, the company's products have come out
of its own design and development efforts.
Today, Tata Motors is India's largest commercial vehicle manufacturer with a 59 per cent market
share and ranks among the top six manufacturers of medium and heavy commercial vehicles in
the areas of business Tata Motors' product range covers passenger cars, multi-utility vehicles as
well as light, medium and heavy commercial vehicles for goods and passenger transport. Seven
out of 10 medium and heavy commercial vehicles in India bear the most trusted TATA mark.

6. MANUFACTURING UNITS
HEAD QUATERS

7. Commercial Vehicle Business unit (CV Unit) :
The company has over 130 models of light, medium and heavy commercial vehicles ranging from
two tones to 40 tones, buses ranging from 12-seaters to 60-seaters, tippers, special purpose vehicles, off-
road vehicles and defense vehicles.
Passenger Car Unit :
The Company’s passenger car range comprises the hatchback Indica, the Indigo sedan and the
Marina, its station wagon variant, in petrol and diesel versions. The Tata Sumo, its rural variant, the Spacio
and the Tata Safari (the country's first sports utility vehicle) are the company's multi-utility offerings. The
Tata Indica, India's first indigenously designed and manufactured car, was launched by Tata Motors in 1999
as part of its ongoing effort towards giving India transport solutions that were designed for Indian
conditions. Currently, the company's passenger cars and multi-utility vehicles have a 16-per cent market
share. .
In addition to the growth opportunities in the buoyant domestic market, the company is pursuing growth
through acquisitions (it acquired Daewoo Commercial Vehicles, Korea, in 2004) and alliances (it has entered
into a tie-up with MG Rover, UK, to supply 1, 00,000 Indicas to be budged as City Rover) in other
geographies.
Research and Development :
Tata Motors invests up to 1.3 per cent of its annual turnover on research and development, with
an emphasis on new product / aggregates development and technology up gradation. Its Engineering
Research Center in Pune has India's only certified crash-test facility and hemi-anechoic chamber for testing
of noise and vibration.

8. The company also draws on the resources of leading international design and styling
houses like the Institute of Development in Automotive Engineering, SPA, Italy and Stile Bertoni,
Italy. The company has also been implementing several environmentally sensitive technologies
in manufacturing processes and uses some of the world's most advanced equipment for
emission checking and control.
Environmental responsibility :
Tata Motors has led the Indian automobile industry's anti-pollution efforts through a
series of initiatives in effluent and emission control. The company introduced emission control
engines in its vehicles in India before the norm was made statutory. All its products meet
required emission standards in the relevant geographies. Modern effluent treatment facilities,
soil and water conservation programs and tree plantation drives on a large scale at its plant
locations contribute to the protection of the environment
Exports :
Tata Motors' vehicles are exported to over 70 countries in Europe, Africa, South
America, Middle East, Asia and Australia. The company also has assembly operations in
Malaysia, Bangladesh, Kenya, South Africa and Egypt.

9. Passenger cars and utility vehicles
• Tata Sierra (Discontinued)
• Tata Estate (Discontinued)
• Tata Sumo/Spacio
• Tata Sumo Grande
• Tata Safari
• Tata Indica
• Tata Vista
• Tata Indigo
• Tata Manza
• Tata Indigo Marina
• Tata Winger
• Tata Magic
• Tata Nano
• Tata Xenon XT
• Tata Aria
• Tata Venture
• Tata Iris

10. Concept vehicles:
• 2000 Aria Roadster
• 2001 Aria Coupe
• 2002 Tata Indiva
• 2004 Tata Indigo Advent
• 2005 Tata Xover
• 2006 Tata Cliffrider
• 2007 Tata Elegante
• 2009 Tata Prima
• 2010 Tata Versa
• 2010 Tata Essota
• 2011 Tata Pixel

11. Commercial vehicles

 Tata Ace
 Tata TL/Telcoline/207 DI Pickup Truck
 Tata 407 Ex and Ex2
 Tata 709 Ex
 Tata 809 Ex and Ex2
 Tata 909 Ex and Ex2
 Tata 1109 (Intermediate truck)
 Tata 1512 (Medium bus chassis)
 Tata 1612/1616 (Heavy bus chassis)
 Tata 1618 (Semi Low Floor bus chassis)
 Tata 1623 (Rear Engined Low Floor bus chassis)
 Tata 1613/1615 (Medium truck)
 Tata 2515/2516 (Medium truck)

12.  Tata Starbus (Branded Buses for city)
 Tata Divo (Fully built luxury coach)
 Tata CityRide (12 - 20 seater buses for intra-city use)
 Tata 3015 (Heavy truck)
 Tata 3118 (Heavy truck) (8×2)
 Tata 4018 (Heavy truck)
 Tata 4923 (Ultra-Heavy truck) (6×4)
 Tata Novus (Heavy truck designed by Tata Daewoo)
 Tata Prima (The World Truck designed by Tata Motors and Tata Daewoo)
Military vehicles::
 Tata 4018 (Heavy truck)
 Tata LSV (Light Specialist Vehicle)
 Tata Mine Protected Vehicle (4×4)
 Tata 2 Stretcher Ambulance
 Tata 407 Troop Carrier, available in
hard top, soft top, 4×4, and 4×2 versions
 Tata LPTA 713 TC (4×4)
 Tata LPT 709 E
 Tata SD 1015 TC (4×4)
 Tata LPTA 1615 TC (4×4)
 Tata LPTA 1621 TC (6×6)
 Tata LPTA 1615 TC (4×2)

14. The plant, rolls out commercial vehicles and is specialized in the designing and
manufacturing of a range of modern buses which includes Low-floor, Ultra Low-floor,
CNG & RE Buses.
The Lucknow facility also specializes in manufacturing HCBS (High capacity Bus System)
buses.
In light of Company’s aggressive growth plans, they are currently in expansion phase and
production at Lucknow would grow many-fold in near future. The expansion shall be in
the areas of painting, welding, vehicle assembly & testing and utility services, driven by
latest technology. To achieve these plans they invite people who have good Technical
Knowledge, seek Challenging Opportunities and have a Drive for Engineering Excellence
to come and partner us in our journey.

15. Tata Motors Lucknow is one of the youngest production facilities among all the Tata Motors
locations and was established in 1992 to meet the demand for Commercial Vehicles in the
Indian market. The state-of-the-art plant is strongly backed by an Engineering Research Centre
and Service set-up to support with latest technology and cater to the complexities of
automobile manufacturing. Fully Built Vehicle business, which is one of the fast growing areas of
our business, is also established in Lucknow.

16. Departments in TATA Motors Lucknow:
 Planning
 Technical services
 Central tool room
 Central procurement
 Dispatch
 Central logistics
 Factory logistics group-CV
 Factory logistics gear-transmission
 Factory logistics Gr-sumo
 SQIG
 Engineering services
 Central maintenance
 FPIG - CV factory
 FPIG-transmission factory
 Central quality (CQ)
 Area office, Lucknow
 Regional sales office (Lucknow)
 Service depts., Lucknow works
 Plant head office
 Manufacturing head office
 Human resources
 Get training
 Business excellence
 Finance
 Internal audit
 ERC Lucknow
 Administration
 Construction

17. The part of the vehicle which constitutes the front part of vehicle and is having all the controls
within the driver’s reach is known
as cowl/cab. The difference between cowl
and cab is that cab is covered from upside,
backside & has windows, while the cowl
Has only the front part with all the controls.
The cowl is received from Jamshedpur in
finished condition, but is being treated here
such as denting & painting so as to remove
the defects occurred during the transportation
before being sent to assembly .Now the BIW
& Paint Shop’s are being erected here in the
Eastern Complex to fabricate the Cowl and Cab here with the capacity of about 520 cabs per
day. The models of the cabs of the trucks which are assembled here are LPS 3518 (Sleeper) and
LPK 2518 (Non-sleeper). All the activities of the trim line 3 are divided into 26 stations, which
are as follows-

18. Stations at Trim Line-3
Station No. 1: (Cab dropping) –
Cab is dropped on the peg, placed on the
slat board with the help of a hoist of 0.5
ton. Inspection card is attached and
reflector sticker is placed on the front
portion.
Station No. 2: (Tapping, Mascot and Mud-guard ) – In this station tapping , mascot and mud
guard assembly is done.

19. Station No. 3: (main wiring harness and wiper motor) – Main wiring harness is fitted and wiper
motor is assembled.
Station No. 4: (Lower and Upper Berth) – Lower and upper berth are installed at this station.
Station No. 5: (DTV Fitment and Hand Brake) – In this station DTV (Dual Treadle Valve) for hand
brake and hand brake is assembled.

20. Station No. 6: (Head Lamps and Blinkers) – Head lamps
and blinkers are installed at this station.
Station No. 7: (Centre Panel) – Centre panel is installed
in the cab at this station. All the wiring of the panel is
done in this station.
Station No. 8: (Insulation and Flange Tube) – Insulated rubber sheets and flanged tube for the suction air
filter inlet are fitted in this station.
Station No. 9: (Wind Shield Glass) – Wind shield glass
is fitted at this station.
Station No. 10: (Seat Belt) – Seat belts are installed at
this station.
Station No. 11: (Door Beading) – Door beading for insulation purpose is installed at this station.

22. Station No. 14: (Air filter) – Air filter for cab is installed in
this station. Air filter filters the air entering the air tank.
This attachment is fitted at this station.
Station No. 15: (Turning Window) – Turning windows are
installed at this station.
Station No. 16: (Dash Board) – Dash boards are installed
at this station.
Station No. 17: (Driver and co-driver Seats) – Fitment of
driver’s seat co-driver’s seats takes place at this station.
Station No. 18: (Steering Column) – Steering columns are
installed at this station.
Station No. 19: (Electrical Inspection) - The various
electrical parts such as head lamps, blinkers etc. are
inspected at this station to check the wiring of cabs

24. Station No. 20: (Instrument Cluster Board) – Speedometer, fuel indicator, distance indicator etc.
are placed on the cluster board. This is fitted in front of the driver’s seat at this station.
Station No. 21:(Steering Wheel) – Steering wheels are
fitted at this station.
Station No. 22:(Auxiliary Water Tank) – Auxiliary water tanks
are installed in this station.
Station No. 23:(Mechanical Inspection) – Inspection like movability of doors and other parts is
done at this station.
Station No. 24:(Mechanical Inspection) – Inspection like movability of doors and other parts is
done in this station.

25. Station No. 25:(Cab Lifting) – Cab
is then lifted for further assembly.
Station No. 26:(Casting Cup) –
Casting cup is fitted at the bottom
of the cab to make an ease for the
chassis fitment (or later casting
cup gets attached with the chassis
of the vehicle).

27. Whenever a cab is sent from the paint shop to the trim line for assembling,
it definitely contains some paint imperfections which have to be removed
before sending it to the next line. Sometimes, certain imperfections occur
at the trim line which also have to be eliminated at the trim line itself.
Paint
Scratch
Paint
Rundown
Paint Not
Done
Paint
Removed

28. I observed around hundred cabs during their assembling processes at
Trim Line 3 and discovered that paint scratches generally occurred at
the following locations:
Inside Central On Stay Rod Door Edge Door Inner
Panel Aperture

29. Near Bottom Near Door Lock Door Face Lower Edge of
Corner Of The Door Central Panel
Near Master Near Door Hinge Door Inner Upper Central Panel
Cylinder Near Window Lock Plate

30. Defect Frequency Percentage
Cumulative
%
Near Door Lock(F) 77 14 14
Stay Rod(B) 74 13 27
Door Inner Upper Near Window(K) 62 11 38
Inside Central Panel(A) 62 11 49
Central Panel Lock Plate(L) 53 9 58
Door Inner Aperture(D) 48 9 67
Door Hinge(J) 43 8 75
Lower Edge of Central Panel(H) 39 7 82
Near Bottom Corner of the door(E) 37 7 88
Door Edge(C) 35 6 94
Near Master Cylinder(I) 19 3 98
Door Face(G) 11 2 100

31. 77 74 62 62 53
48 43 39 37 35 19 11
14
27
38
49
58
67
75
82
88
94 98 100
0
10
20
30
40
50
60
70
80
90
100
0
100
200
300
400
500
Cumulative%
FrequencyOfDefects
Defects
Paint Scratch Pareto

32.  Near Door Lock
 Possible Causes of Scratch:
(a) & (b):
1. Inappropriate size of holes.
2. Carelessness done by the worker while fitting the screws.
3. Hammering done on the male part of the lock to fix
it in the female part dislocates it and in that dislocation the
bolts and washers fixing the lock create the scratch.
(c):
1. When the lock is not fitted properly, sometimes the edge of
the female part rubs with the door surface near the male
part, when the door is closed and creates a scratch.
2. Insufficient gap at door’s inner edge.
3. Depth of the striker may be inappropriate.
4. Insufficient gap at door’s outer edge.
a
b
c

33.  Validation of Causes:
(a) & (b):
1. Inappropriate size of holes:
The appropriate diameter of holes at a & b should be 6mm
according to drawing and the diameter of holes recorded,
were as follows:
Cab Number Diameter of Holes at 'a' Diameter of Holes at 'b'
8168 6.02mm 6.06mm
8169 6.08mm 6.02mm
8170 6.06mm 6.08mm
8171 6.04mm 6.02mm
8157 6.06mm 6.06mm
Since the diameter of holes lie within the tolerance
limit of the designed diameter, this can not be the
cause of scratch.
a
b
2: Carelessness done by the worker while fitting the screws:
I observed around ten cabs and found that workers were fitting the screws
carefully and properly. So, this can not be the cause of scratch.

34. 3. Hammering done to fix the male part of the lock in the female part
properly, shifts the male part towards the door edge which dislocates
the bolts and washers fixing it and a scratch is created:
It was observed in every cab that these scratches were getting created by
hammering. So, this is the root cause of scratches at a & b.
(c):
1. When screws of the lock is not tightened, the edge of the
female part rubs with the door surface near the male part,
when the door is closed and creates a scratch:
To check for this cause I observed five cabs between stations where the
door lock was fixed and where it’s screws were tightened and tabulated as:
Cab Number
Did any scratch get created in
between the two stations?
8168 NO
8169 YES
8170 NO
8171 NO
8157 NO
c

35. Only 1 out of 5 cabs obtained scratch so, this can not be the root
cause of scratch.
2. Insufficient gap at door’s inner edge:
I checked door gap in the region ‘x’ and tabulated as:
Cab Number Door Gap At ‘x’ Occurrence of Scratch at 'c'
8168 8mm NO
8169 7.5mm YES
8170 8.5mm YES
8171 8mm YES
8157 9mm YES
8172 8.5mm NO
8173 7mm YES
8174 9mm NO
Since no relation could be established between the door gap at inner edge
and occurrence of scratch, it can not be the cause of scratch ‘c’.
However, when the door gap was less than 8mm, a different scratch was
obtained at x due to fouling.
x
c

36. 3. Inappropriate depth of the striker:
I checked the depth of strikers in 5 cabs and tabulated them as:
Since no relation could be established between the depth of striker and
occurrence of scratch, it can not be the cause of scratch ‘c’.
Cab Number Depth of Striker Occurrence of Scratch
8174 25.10mm NO
8158 25.06mm YES
8175 25.04mm NO
8176 24.84mm NO
8177 25.12mm YES
h

37. 4. Insufficient gap at door’s outer edge:
I checked door clearance in the region ‘A’, ‘B’, ‘C’ and tabulated as:
When the door gap was less than 6mm at region ‘B’, this scratch was
obtained due to fouling. Hence, this is the root cause of this scratch.
C
B
A
Cab Number Door Gap At A Door Gap At B Door Gap At C Occurance of Scratch
8168 6.5mm 6mm 6mm NO
8169 6mm 4.5mm 6.5mm YES
8170 6.5mm 4mm 6mm YES
8171 6mm 5mm 4.5mm YES
8157 4.5mm 4.5mm 6.5mm YES
8172 6mm 6.5mm 6mm NO
8173 6.5mm 4.5mm 6mm YES
8174 6.5mm 6.5mm 6mm NO
8158 7mm 4.5mm 6mm YES
8175 4mm 6mm 6.5mm NO
8176 6mm 7mm 4.5mm NO
8177 6mm 5mm 5.5mm YES
Star Gauge used to
find door gap

38.  Prevention From Scratches:
(a) & (b):
As in most of the cabs the male part does not fix inside the
female part properly(Hard Locking) and hammering shifts the
male part towards the outer edge which fixes it inside the
female part.
The gaps ‘a’ & ‘b’ which were initially almost same now
changes. They were recorded as:
ba
Cab Number Gap 'a' Gap 'b'
Before
Hammering After Hammering
Before
Hammering After Hammering
8168 5.06mm 2.34mm 4.86mm 7.88mm
8169 5.04mm 2.46mm 5.06mm 7.64mm
8170 4.92mm 2.26mm 5.02mm 7.68mm
8171 5.10mm 2.28mm 5.04mm 7.86mm
8157 4.94mm 2.54mm 5.08mm 7.48mm
5 mm 5 mm
5 mm
Hammering can be avoided if instead of shifting the male part we
shift the female part. This can be achieved if the holes provided
for screws to fit the female part are shifted radially by a small
distance(around 2.5mm). Therefore total shift will be around
5mm.

39. A simpler method adopted by the workers is by using a hard
metallic tool(screwdriver) which they fix at the end near
gap ‘b’ and apply a downward force on it. This pushes the
male part towards the outer door edge and decreases gap
‘a’. At the same time another worker tightens the screws
and fits the lock. This prevents the scratch from getting
created.
For safety purpose, a rubber handle can be used to cover
the metallic side of the tool.
(c):
1. By providing more door gap(6mm-8mm) at the outer edge
of the door.
2. A wooden stopper is used at the lock fixing station to
prevent the closing of door until the lock is fitted.
3. The fixing and fitting of the door lock are done at the
same station.
Door Gap
Wooden stopper to
prevent closing of
door

40. On Stay Rod
(a):
 Possible Causes of Scratch:
1: Inappropriate thickness of the stay rod.
2: The stay rod holder might create scratch on it.
3: No specific resting place for stay rod at the time the cab comes to Trim Line.
.

42.  Validation of Causes:
1: Inappropriate thickness of stay rod:
The thickness of stay rod was recorded as:
Since, the thickness was according to the drawing and had no relation
with the scratch, this is not a cause of scratch.
Cab Number Thickness of Stay Rod Occurrence of Scratch
8168 8.08mm YES
8169 8.12mm YES
8170 8.18mm NO
8171 8.04mm YES
8157 8.10mm NO
x

43. 2: The stay rod holder might create scratch on it:
To check for this cause, I calculated the diameter
of stay rod holder and found that:
Cab Number Diameter of Stay Rod Holder Occurrence of Scratch
8168 8.68mm YES
8169 8.52mm YES
8170 8.56mm NO
8171 8.64mm YES
8157 8.54mm NO
Since, the diameter was according to the drawing and had no relation
with the scratch, this is not a cause of scratch. Further it was made up of
a non metallic material, so creation of scratch was hardly possible.

44. 3: No specific resting place for stay rod at the time the cab comes to Trim Line :
To check for this cause, I went to the dropping
station and found that this scratch came from the
paint shop.
In the absence of stay rod holder at the
BIW shop, the stay rod is unable to rest at
a particular place. When the central panel
is closed, the stay rod doesn’t comes back
to it’s resting place, most of the time and
consequently hits the inside of the central
panel.
When this cab is painted in the paint shop,
this hitting creates a visible scratch on the
central panel.
Hence, this is the root cause of this scratch.

45. This is one of the most occurring scratches in the cab and can be eliminated only if the
stay rod holder is fitted in the BIW shop instead of Trim Line. This will reduce one
process in the trim line and will also prevent formation of such scratches in future.
 Prevention From Scratch:

46. Central Panel Lock Plate
(a):
 Possible Causes of Scratch:
1: In the absence of rubber buffer near the lock plate, before reaching the trim
line, the inside of the central panel hits the lock plate and creates this scratch.
2: Unskilled labour.
3: For proper locking of the Central Panel, the lock plate is bended using a
metallic tool which creates scratch on its edges.
4: Some lock plate might be harder than others.
.
a

47.  Validation of Causes:
1: In the absence of rubber buffer near the lock plate, before the cab reaches
the trim line, the inside of the central panel hits the lock plate and creates this
scratch:
To check for this cause, I went to the dropping station. I looked for this scratch in ten cabs
but found it in none. So, I concluded that this can not be a cause of this scratch.

48. 2: Unskilled labour:
To check for this cause, I went to the station where bending of lock plate is done. I
observed this bending in ten cabs and found that only four of them got scratches. So, I
further introspected about the worker doing this job. In four days, four workers did that
job. Their work is tabulated as:
Day 1 Day 2 Day 3 Day 4
Morning
Shift
Evening
Shift
Morning
Shift
Evening
Shift
Morning
Shift
Evening
Shift
Morning
Shift
Evening
Shift
Worker A Worker B Worker A Worker C Worker A Worker B Worker D Worker B
Work Experience 3 Months
1.5
Months 1 Month
1.5
Months
Occurrence of Paint
Scratch in 10 cabs
3 5 4 6 4 5 4 4
To some extent we can say that workers do make mistake and unskilled labour is a cause
of this scratch.

49. 2: For proper locking of the Central Panel, the lock plate is bended using a
metallic tool which creates scratch on its edges:
Conventionally used
tool for bending
To check for this cause, I went to the station where bending of lock plate is done. I looked
for this scratch in ten cabs and found that it was getting created there only. So, I
concluded that this tool is a cause of this scratch. But, not all cabs were developing the
scratch. Therefore it is not the root cause of this scratch.

50. To check for this cause, I went to the station where bending of lock plate is done. I
observed two cabs while bending was being done. One cab got the scratch and the other
did not. Then, I myself tried to bend the two lock plates and felt the difference in
hardness between the two. So, I tabulated my observations for the next five cabs as:
4: Some lock plate might be harder than others:
Cab Number Hard Lock Plate
Occurrence of
Scratch
8174 NO NO
8158 YES YES
8175 NO NO
8176 NO NO
8177 YES YES
Since hardness of lock plate has a direct relation with occurrence of scratch, it is the root
cause of this scratch.

51. Scratch at a can be eliminated by avoiding metal to metal contact between the tool and
the lock plate.
This can be achieved by using plates of a hard non metallic material(like acrylic) in the jaws of
the conventionally used metallic tool.
 Prevention From Scratch:

52. (b):
 Cause of Scratch:
Due to very less space provided for fitting the shocker in sleeper cabs and due to
worker’s carelessness, the shocker or the nut tightening gun sometimes rubs on this
region. This scratch was found in 8 out of 100 cabs.
b
Plastic coated masking tapes can
be applied in the scratch prone
regions before fitting their nearby
components.
Plastic Coated masking
tape
Plastic coated tape can be made in line only by applying brown tape over the
conventionally used masking tape.
 Prevention From Scratch:

53. Lower Edge of Central Panel
 Possible Causes of Scratch:
1: Workers’ carelessness during fitment of parts near central panel.
2: Height of some pegs might not be appropriate.
3: In some cabs the gap at the top edge of central panel might be more than needed.
4: Some cabs might not properly rest over the peg which cause them to lean down
from the front.

55.  Validation of Causes:
1: Workers’ carelessness during fitment of parts near central panel:
I observed the fitments near central panel in five cabs and found that workers were not
responsible for this scratch.
Hence, it was not a cause of this scratch.

56. 2: Height of some pegs might not be appropriate which might bring
them to the level of central panel:
To check for this cause, I checked the height of ten pegs and tabulated
them as:
The height of all the pegs had impact on the formation of scratch to some extent.
But, in some cabs(mainly LPS) the height was more than required but still the scratch
didn’t create. Therefore this can be a cause of this scratch, but not the root cause.
Height Of Peg Occurrence of Scratch
60.4cm NO
58.5cm NO
60.8cm NO
62.2cm YES
62.6cm YES
61.5cm NO
62.3cm YES
59.2cm NO
61.5cm YES
61.7cm NO

57. 3: In some cabs the gap at the top edge of central panel might be more
than needed. This lowers the central panel and might bring it to the height
of the peg:
In some cabs it might be possible that the gap provided at the top edge of central
panel be more than it should be. So, I checked for this cause in five cabs and tabulated
as:
There was no relation between the gap at the top edge and the formation of
scratch. Therefore, I concluded that this was also not a cause of this scratch.
Gap 'x'
Occurrence of
Scratch
156mm NO
154mm NO
160mm NO
154mm NO
158mm YES
x

58. 4: Some cabs might lean down more from the front than others:
Resting points of sleeper and non sleeper cabs were different which caused the non
sleeper(LPK) cabs to lean down more from the front than sleeper(LPS) cabs.
Resting point
of LPK
Resting point
of LPS
To check whether this might be the cause of this scratch, I observed three LPK cabs
and three LPS cabs and tabulated as follows:

59. This cause was observed in all the cabs that had this scratch and hence is the
root cause of this scratch.
h
LPK LPS
Cab
Number Height 'h'
Cab
Number Height 'h'
8173 125.8cm 8157 128.2cm
8174 124.8cm 8158 127.8cm
8175 126.2cm 8159 128.6cm
On an average this height ‘h’ should be more
than the sum of heights of central panel and the
peg individually to avoid the formation of scratch.
Average Height of Central Panel(65cm) +
Average Height of Peg(60cm) = 125cm
Therefore cabs having height ‘h’ less than or
equal to 125 will obtain the scratch.

60. This scratch can be avoided if we raise the cab to a height that under no conditions the
central panel touches the peg.
This has been implemented by using rubber pads below the acrylic plates fitted at points where
the cab rests on the peg. This adjustment raises the cab to 1.0-1.5cm more height above the
peg.
 Prevention From Scratch:

61. A permanent solution to this problem is by replacing all the currently used acrylic
plates with thicker plates, so that they produce the same effect as the combination
of currently used plates and rubber pads have.
However, not all pegs have this adjustments. In some, either the rubber pads
have been damaged or have got removed due to poor maintenance.

62. Door Face
 Possible Causes of Scratch:
(1): If door cover is not applied, scratches can be caused by any metallic object coming in
its way.
(2): If metal dust get stuck to the magnets on the inner side of the covers, they rub with the
door face.
 Prevention From Scratch:
(1): Proper door covers should
be applied throughout the line.
Further, care should be taken
by workers that no metallic
object rubs the door. Cotton-
made watch covers and belt
covers should be worn by the
workers before coming to the
line.

63. (2):
Normal door cover
attracts dust of
metal which
sooner or later
creates scratches.
Masking tapes are
used to avoid the
sticking of metallic
dust.
However, masking
tapes are not
completely reliable
and some metallic
dust still stick over
it. So, they are
required to be
brushed at regular
intervals.
Plastic coated
masking tapes do
not allow metal
dust to stick on it
and hence are
preferable.

64. Door Inner Upper Near Window
 Causes of Scratch:
(1) Worker’s carelessness during (2) For fitting the channel inside the window hammering is
inserting the channel. done at the corners of the channel. Since there is hardly any
clearance provided between the channel and window, the
channel while fitting inside creates scratches on the
window.

65.  Prevention From Scratch:
(1): Worker should carefully insert the channel inside the window, taking care
that it does not touches the window.
(2): This scratch can be prevented by avoiding hammering and that will be
possible if we provide some clearance between the window and channel.
Further, if we use a proper hammer then also this scratch can be prevented to
some extent.
Damaged Hammer Proper Hammer

66. 1. Assembling
processes will be
more efficient after
improvements.
2. No extra process
for fixing the
scratches will be
required.
3. Time
consumption will
be less.
4. Quality of work
will be improved.
5. It will decrease
the total cost of
production.