Shaper - Types of operations. Drilling, reaming, boring, Tapping. Milling operations-types of milling cutter. Gear cutting – forming and generation principle and construction of gear milling, hobbing and gear shaping processes –finishing of gears.

1. Manufacturing technology- II
Unit 3 - OTHER MACHINE TOOLS
P.RAM KUMAR M.E.,
ASSISTANT PROFESSOR
MECHANICAL ENGINEERING

2. UNIT III - OTHER MACHINE TOOLS
Shaper - Types of operations. Drilling, reaming, boring, Tapping.
Milling operations-types of milling cutter. Gear cutting – forming and
generation principle and construction of gear milling, hobbing and gear
shaping processes –finishing of gears.
1. Hajra Choudhury, "Elements of Workshop Technology", Vol.II.,
Media Promoters.
2. Rao. P.N “Manufacturing Technology - Metal Cutting and Machine
Tools", Tata McGraw-Hill, New Delhi, 2003

3. SHAPER MECHANISM
In a shaper, rotary motion of the drive is converted into reciprocating
motion of the ram by the mechanism housed within the column or the
machine
In a standard shaper metal is removed in the forward cutting stroke,
while the return stroke goes idle and no metal is removed during this
period
Classifications:
(1) Crank and slotted link mechanism
(2) Whitworth quick return mechanism
(3) Hydraulic shaper mechanism

4. Crank and slotted link mechanism

5. Crank and slotted link mechanism
In crank and slotted link mechanism , the pinion receives its motion
from an individual motor or overhead line shaft and transmits the
motion or power to the bull gear.
Bull gear is a large gear mounted within the column. Speed of the bull
gear may be changed by different combination of gearing or by simply
shifting the belt on the step cone pulley.
A radial slide is bolted to the Centre of the bull gear. This radial slide
carries a sliding block into which the crank pin is fitted.
Rotation of the bull gear will cause the bush pin to revolve at a
uniform speed. Sliding block, which is mounted upon the crank pin is
fitted within the slotted link.

6. Whitworth quick return mechanism

7. Whitworth quick return mechanism
The Whitworth quick return mechanism converts rotary motion into
reciprocating motion, but unlike the crank and slider, the forward
reciprocating motion is at a different rate than the backward stroke.
 At the bottom of the drive arm, the peg only has to move through a
few degrees to sweep the arm from left to right, but it takes the
remainder of the revolution to bring the arm back. This mechanism is
most commonly seen as the drive for a shaping machine.

8. Hydraulic shaper mechanism

10. Feed Mechanism
1. Hand feed
2. Automatic table feed (Paul and ratchet mechanism)

11. Automatic table feed( Paul and ratchet mechanism)

12. Hand feed

13. Work Holding Devices in shaper machine
1. Vices
2. Clamps
3. Angle plate
4. Parallel strips
5. Jack
6. Centers
7. V- block
8. Stop pin and Toe dogs

14. Vices
• The shaper vice has a robust
construction as compared then
other vice
• Jaw of a shaper vice long and
deep we can fix large shaped
workpiece
• Prevent from distorted or marked
by the work piece

15. Clamps
• Commonly used device in shaper
machine
• Generally to fit the table slots T
head bolds are used and their
body provided with sufficient
thread so we can used different
work piece
• According to various shape and
size different clamp used

16. Angle plate
• Angle plate made in cast iron
• Angle plate is bolted to the
machine table on one side other
side is bolted to the work piece
• Irregular workpiece held by
angle plate

17. V- block
• Made by steel or cast iron
• Using to hold which are too
small in diameter
• Held horizontal alignment by
using v block
• Between two v block the shaper
tool is reciprocate cut and groove
or keyway on the round
workpiece

18. Stop pin and Toe dogs
• Stop pin and Toe dogs are used
hold the thin workpiece
• Stop pin can be inserted in the
provided slot in the table
• Toe-dog forced against the work
piece by tightening the stop pin

19. DIFFERENCE BETWEEN SHAPER AND PLANER

21. MILLING MACHINE
1. Milling is the cutting operation that removes metal by feeding the
work against a rotating, cutter having single or multiple cutting
edges.
2. Flat or curved surfaces of many shapes can be machined by milling
with good finish and accuracy
3. A milling machine may also be used for drilling, slotting, making a
circular profile and gear cutting by having suitable attachments.

22. MILLING MACHINE

23. MILLING MACHINE CONSTRUCTION
Base:
• It gives support and rigidity to the machine and also acts as a
reservoir for the cutting fluids.
Column:
• The column is the main supporting frame mounted vertically
on the base.
• The column is box shaped, heavily ribbed inside and houses
all the driving mechanisms for the spindle and table feed

24. CONSTRUCTION
Knee:
• The knee is a rigid casting mounted on the front face of the column.
• The knee moves vertically along the guide ways and this movement enables
to adjust the distance between the cutter and the job mounted on the table.
• The adjustment is obtained manually or automatically by operating the
elevating screw provided below the knee
Elevating screw:
• The upward and downward movement to the knee and the table is given
by the elevating screw that is operated by hand or an automatic feed.

25. CONSTRUCTION
Overarm:
• The Overarm is mounted at the top of the column and is guided in
perfect alignment by the machined surfaces. The Overarm is the support
for the arbor.
Arbor support:
• The arbor support is fitted to the Overarm and can be clamped at any
location on the Overarm. Its function is to align and support various
arbors. The arbor is a machined shaft that holds and drives the cutters.

26. CONSTRUCTION
Table:
• The table rests on guide ways in the saddle and provides support to the
work.
• The table is made of cast iron, its top surface is accurately machined
and carriers T-slots which accommodate the clamping bolt for fixing the
work.
• The worktable and hence the job fitted on it is given motions in three
directions

27. CONSTRUCTION
Saddle:
• The saddle rests on the knee and constitutes the
intermediate part between the knee and the table.
• The saddle moves transversely, i.e., crosswise (in or out)
on guide ways provided on the knee.

28. MILLING MACHINE

29. Working Principle
The work piece is holding on the worktable of the machine.
The table movement controls the feed of work piece against the
rotating cutter.
The cutter is mounted on a spindle or arbor and revolves at high
speed.
Except for rotation the cutter has no other motion.
As the work piece advances, the cutter teeth remove the metal from
the surface of work piece and the desired shape is produced.

30. MILLING METHODS
There are two distinct methods of milling classified a follows:
1. Up-milling or conventional milling, and
2. Down milling or climb milling.

31. UP-Milling or Conventional Milling Procedure
• In the up-milling or conventional milling, the metal is removed in
form of small chips by a cutter rotating against the direction of travel of
the workpiece.
• In this type of milling, the chip thickness is minimum at the start of the
cut and maximum at the end of cut.

32. Down-Milling or Climb Milling
Down milling is also known as climb milling.
• In this method, the metal is removed by a cutter rotating in the same
direction of feed of the workpiece.
• The effect of this is that the teeth cut downward instead of upwards.
• Chip thickness is maximum at the start of the cut and minimum in the
end.

33. TYPES OF MILLING MACHINES
According to general design, the distinctive types of milling
machines are
1. Column and knee type milling machines
(a) Hand milling machine
(b) Horizontal milling machine
(c) Universal milling machine
(d) Vertical milling machine
2. Planer milling machine
3. Fixed-bed type milling machine
(a) Simplex milling machine.
(b) Duplex milling machine.
(c) Triplex milling machine.

34. TYPES OF MILLING MACHINES
4. Machining center machines
5. Special types of milling machines
(a) Rotary table milling machine.
(b) Planetary milling machine.
(c) Profiling machine.
(d) Duplicating machine.
(e) Pantograph milling machine.
(f) Continuous milling machine.
(g) Drum milling machine
(h) Profiling and tracer controlled milling machine

35. Column and knee type milling machines
Vertical milling machine Horizontal milling machine

36. Universal milling machine

37. Hand milling machine

38. MILLING CUTTERS NOMENCLATURE

39. TYPES OF MILLING CUTTERS
• PLAIN MILLING CUTTERS
• SIDE MILLING CUTTERS
• SHELL END MILLS
• ANGULAR CUTTERS
• FORMED CUTTERS
• METAL-SLITTING SAWS

40. TYPES OF MILLING CUTTERS

41. PLAIN MILLING CUTTERS
Plain Milling Cutters
• Most widely used( dia 16-160 width 20-160mm)
• Cylinder of high-speed steel with teeth cut on periphery
• Used to produce flat surface
Several types
• Light-duty
• Light-duty helical
• Heavy-duty
• High-helix

42. Light-Duty Plain Milling Cutter
• Less than ¾ in wide, straight teeth (20mm width)
• Used for light milling operations
• Those over ¾ in have helix angle of 25°
• Too many teeth to permit chip clearance
• this is used for key way or slot cutting

43. HEAVY-DUTY PLAIN MILLING
CUTTERS
• Have fewer teeth than light-duty type
• Provide for better chip clearance
• Helix angle varies up to 45°
• Produces smoother surface because of shearing action and reduced
chatter
• Less power required

44. HIGH-HELIX PLAIN MILLING CUTTERS
• Have helix angles from 45° to over 60 °
• Suited to milling of wide and intermittent surfaces on contour and
profile milling
• Usually mounted on milling machine arbor
• Sometimes shank-mounted with pilot on end and used for milling and
gated slots.

45. SIDE MILLING CUTTERS
• Comparatively narrow cylindrical milling cutters with teeth on each
side and on periphery
• Used for cutting slots and for face straddle milling operations
• Free cutting action at high speeds and feeds
• Suited for milling deep, narrow slots Staggered Straight

46. HALF-SIDE MILLING CUTTERS
• Used when only one side of cutter required
• Also make with interlocking faces so two cutter may be placed side by
side for slot milling
• Have considerable rake
• Able to take heavy cuts.

47. SHELL END MILLS
• Face milling cutters under 6 in.
• Solid, multiple-tooth cutters with teeth on face and periphery
• Held on stub arbor
• May be threaded or use key in shank to drive cutter

48. ANGULAR CUTTERS
Single-angle
▫Teeth on angular surface
▫May or may not have teeth on flat
▫45° or 60°
Double-angle
▫Two intersecting angular surfaces
with cutting teeth on both
▫Equal angles on both side of line
at right angle to axis

49. TYPES OF FORMED CUTTERS
Convex milling cutter:
• Used to producing concave surface on work
piece
• Diameter 50-125 mm
Concave milling cutter:
• Used to producing convex surface on work
piece
• Diameter 56 -110 mm
Gear cutter:
• This process is used for milling operations such
us cutting teeth of worm wheel, helical and spur
gear, spline shaft Concave Convex Gear Tooth

50. METAL-SLITTING SAWS
• Very small width of cut
• Mostly used for part off operations and
slotting
Plain slitting cutter:
• compered to other cutter is very thin
• Width range is 1-5 mm
Staged teeth slitting cutters
• This cutter used for heavy work only
• Width range is 4-10 mm
Metal slitting plain cutter staged teeth slitting
cutters

51. T-SLOT CUTTER
Used to cut wide horizontal groove at bottom of T-slot
• After narrow vertical groove machined with end mill or side
milling cutter
• Consists of small side milling cutter with teeth on
both sides and integral shank for mounting

52. DOVETAIL CUTTER
• Similar to single-angle milling cutter with integral shank
• Used to form sides of dovetail after tongue or groove machined
• Obtained with 45º, 50º, 55º, or 60º angles

53. WOODRUFF KEY SEAT CUTTER
• Similar in design to plain and side milling cutters
• Small (up to 2 in) solid shank, straight teeth
• Large mounted on arbor with staggered teeth
• Used for milling semi cylindrical key seats in
shafts
• Designated by number system

54. OPERATIONS PERFORMED ON
MILLING MACHINE
Slab / Plain Milling
Slab / Plain Milling The basic
form of peripheral milling in
which the cutter width extends
beyond the workpiece on both
sides

55. Slotting
Width of cutter is less than
workpiece width, creating a slot in
the work

56. Conventional Face Milling
• Cutter overhangs work on both
sides
• conventional face milling

57. End Milling
Cutter diameter is less than work
width, so a slot is cut into part

58. Profile Milling
• A form of end milling in which
the outside periphery of a flat
part is cut

59. Pocket Milling
• Another form of end milling
used to mill shallow pockets into
flat parts

60. Surface Contouring
• Ball-nose cutter is fed back and
forth across the work along a
curvilinear path at close intervals
to create a three dimensional
surface form

61. GEAR GENERATION AND FINISHING
OPERATIONS
INTRODUCTION:
• Gear is one of the important machine tool elements which is an
integral and inevitable part of power transmission system.
• A gear is a round blank having teeth along its periphery.
• Gears are used to transfer power or torque from prime mover to the
place where it is to be used.
• Along with the transmission of power gears also transfer the accurate
velocity ratio between two shafts.

62. INTRODUCTION:
• Power Transfer between Driver and Driven Gears

63. METHOD OF GEAR MANUFACTURING
In broader sense the gears can be manufactured by the following three
methods.
1. Casting
2. Plastic Moulding
3. Machining
i. Gear Forming
ii. Gears Shaping
a) Gear cutting by gear shaper.
b) Rack planning process.
c) Hobbing process

64. METHOD OF GEAR MANUFACTURING
Gear forming- where the profile of the teeth are obtained as the replica
of the form of the cutting tool (edge); e.g., milling, broaching etc.
Gear generation- where the complicated tooth profile
are provided by much simpler form cutting tool (edges)
through rolling type, tool – work
motions, e.g., hobbing, gear shaping etc

65. Gear forming- Milling

66. Gear Shaping :
1.Gear Cutting by Gear Shaper:
Process of Gear Cutting by Shaper Cutter

67. Gear Cutting by Gear Shaper
Setup for Gear Shaping Machine

68. Advantages of Gear Shaping Process
• Shorter product cycle time and suitable for making medium and large
sized gears in mass production.
• Different types of gears can be made except worm and worm wheels.
• Close tolerance in gear cutting can be maintained.
• Accuracy and repeatability of gear tooth profile can be maintained
comfortably.
• For same value of gear tooth module a single type of cutter can be
used irrespective of number of teeth in the gear.

69. Limitations of Gear Shaping Process
• It cannot be used to make worm and work wheel which is a particular
type of gear.
• There is no cutting in the return stroke of the gear cutter, so there is a
need to make return stroke faster than the cutting stroke.
• In case of cutting of helical gears, a specially designed guide
containing a particular helix and helix angle, corresponding to the teeth
to be made, is always needed on urgent basis.

70. Gear Shaping by Rack Shaped Cutter
Gear Cutting by Rack Shaped Cutter

71. Gear Hobbing Process

72. Gear Hobbing Process

73. GEAR FINISHING OPERATIONS
• Surface of gear teeth produced by any of the generating process is not
accurate and of good quality (smooth).
• Commonly used gear finishing operations are described below.
▫ Gear Shaving
▫ Roll Finishing of Gear Tooth
▫ Gear Burnishing
▫ Gear Honning

74. Drilling Machines
• Principle of rotating tool to make hole
• One of most common and useful machines in industry
• Come in several types and sizes
▫ From hand-fed to computer-controlled

75. Construction Details and Operation

76. Standard Operations
• Drilling
▫ Operation of producing hole by
removing metal from solid mass
using twist drill
• Counter sinking
Operation of producing tapered
or cone-shaped enlargement
to end of hole

77. Standard Operations
• Reaming
Operation of sizing and producing
smooth, round hole from previously
drilled or bored hole
• Boring
Truing and enlarging hole by
means of single-point cutting tool

78. Standard Operations
• Tapping
Cutting internal threads in hole
with cutting tool called tap
• Counter boring
Enlarging top of previously
drilled hole to given depth
to provide square shoulder for
head of bolt or capscrew

79. Types of Drilling Machines
1. Portable drilling Machine
2. Sensitive Drill Press Parts
3. Radial Drilling Machine
4. Gang Drilling Machine
5. Up right Drilling Machine

80. Portable drilling Machine
• Only hand feed mechanism,
Manual operated machine
• Hand drilling machine

81. Sensitive Drill Press Parts
• Only hand feed mechanism
▫ Control down feed pressure
• Manufactured in bench and floor
model
• Four main parts
▫ Base, column, table and drilling
head

82. Radial Drilling Machine

83. Tool-Holding Devices
• Drill press spindle provides means of holding and driving cutting tool
• End may be tapered or threaded for mounting drill chuck
• Most common
▫ Drill chucks
▫ Drill sleeves
▫ Drill sockets

84. Drill Chucks
• Most common devices used for holding straight-shank cutting tools
• Most contain three jaws that move simultaneously when outer sleeve
turned
▫ Hold straight shank of cutting tool securely
• Two common types
▫ Key
▫ Keyless

85. Chucks
• Hold straight-shank drills
• Mounted on drill press spindle
Taper
Threads
• Held in spindle by self-holding
taper in larger machines
• Four types of drill chucks

86. Types of Drill Chucks
• Key-type
▫ Most common
▫ Three jaws move simultaneously when outer
sleeve turned
• Tighten with key
• Keyless
▫ Chuck loosened or tightened by hand without key
• Precision keyless
▫ Holds smaller drills accurately

87. Types of Drill Chucks
• Jacobs impact keyless chuck
▫ Hold small or large drills accurately using
Rubber-Flex collets
▫ Gripped or released quickly and easily by
means of built-in impact device in chuck

88. Drill Sleeves and Sockets
• Drill Sleeves
▫ Used to adapt cutting tool shank
to machine spindle if taper on tool
is smaller than tapered hole in
spindle
• Drill Socket
▫ Used when hole in spindle of
drill press to small for taper shank
of drill
▫ Used also as extension sockets

89. Work-Holding Devices
• Angle vise
▫ Angular adjustment on base to allow operator to drill holes at an angle
without tilting table
• Drill vise
▫ Used to hold round, square or odd-shaped rectangular, pieces
▫ Bolt vise to table for stability

90. • Contour vise
▫ Has special movable jaws that automatically adjust to shape of odd-
shaped workpiece
• V-blocks
▫ Made of cast iron or hardened steel
▫ Used in pairs to support round work for drilling
• Step blocks
▫ Used to provide support for outer end of strap
clamps
▫ Various sizes and steps

91. Three Main Parts of Drill

92. Manufactured from three main materials
▫ Carbon-steel drills
Used in hobby shops not for machine shop work
Cutting edges wear down quickly
▫ High-speed steel drills
Used in machine shop work
Cutting edges withstand more heat and wear
▫ Cemented-carbide drills
Operated at high speeds, withstand

93. Drilling Facts and Problems
• Excessive speed
• Excessive clearance
• Excessive feed
• Insufficient clearance
• Cutting lips with unequal angles
• Cutting lips with unequal in length
• Loading and galling