Traditional machining processes use machine tools like lathes, mills, and drill presses with sharp cutting tools to remove material from a workpiece. Positive rake angles on cutting tools reduce cutting forces but weaken the tool, while negative rake angles strengthen the tool but increase forces. Common machining operations include turning, drilling, milling, grinding, planing, sawing, and stamping/pressing, each using different types of tools and machines to cut or form various geometries in materials. Gear cutting involves using a specialized cutter and dividing head to mill gear teeth according to the involute profile.

1. TRADITIONAL MACHINING (TM)
Introduction
In these "traditional" or "conventional" machining processes, machine tools, such as
lathes, milling machines, drill presses, or others, are used with a sharp cutting tool to remove
material to achieve a desired geometry.
A cross-sectional view of the machining process
a) tool with positive rake angle b) tool with negative
rake angle
Positive rake angles:
 Make the tool more sharp and pointed. This reduces the strength of the tool, as the small
included angle in the tip may cause it to chip away.
 Reduce cutting forces and power requirements.
 Helps in the formation of continuous chips in ductile materials.
 Can help avoid the formation of a built-up edge.
Negative rake angles:
 Make the tool more blunt, increasing the strength of the cutting edge.
 Increase the cutting forces.
 Can increase friction, resulting in higher temperatures.
 Can improve surface finish.

2. Review process
Material Removal Processes
• Machining – material removal by a sharp cutting tool, e.g., turning, milling, drilling
• Abrasive processes – material removal by hard, abrasive particles, e.g., grinding
• Nontraditional processes - various energy forms other than sharp cutting tool to
remove material
• Machining in manufacturing sequences
Machining operations and machine tools
1. Turning
• Turning is a form of machining, a material removal process, which is used to create
rotational parts by cutting away unwanted material. The turning process requires
a turning machine or lathe, workpiece, fixture, and cutting tool. There are variations
of turning performed on a lathe such as facing, contour turning, chamfering, cutoff
and threading.

3. 2. Drilling
Drilling is a cutting process that uses a drill bit to cut a hole of circular cross-section in solid
materials. The drill bit is usually a rotary cutting tool, often multipoint. The bit is pressed
against the workpiece and rotated at rates from hundreds to thousands of revolutions per
minute.
3. Milling
Milling is the machining process of using rotary cutters to remove material from a workpiece
by advancing (or feeding) in a direction at an angle with the axis of the tool. It covers a wide
variety of different operations and machines, on scales from small individual parts to large,
heavy-duty gang milling operations. There are two form of milling which peripheral milling
and face milling.

4. 4. Grinding
A grinding machine, often shortened to grinder, is any of various power tools
or machine tools used for grinding, which is a type of machining using an abrasive wheel as
the cutting tool. Each grain of abrasive on the wheel's surface cuts a small chip from the
workpiece via shear deformation.
5. Shaper
Planing (shaping) Planing is a manufacturing process of material removal in which the
workpiece reciprocates against a stationary cutting tool producing a plane or sculpted surface.
Planing is analogous to shaping.

5. 6. Power saw
Sawing is a process wherein a narrow slit is cut into the workpiece by a tool consisting of a
series of narrowly spaced teeth, called a saw blade. Sawing is used to separate work parts into
two or more pieces, or to cut off an unwanted section of a part. These processes are often
called cut-off operations and since many manufacturing projects require cut-off operations at
some point in the production sequence, sawing is an important manufacturing process.
7. Presses
Stamping (also known as pressing) is the process of placing flat sheet metal in either blank or
coil form into a stamping press where a tool and die surface forms the metal into a net shape.
Stamping includes a variety of sheet-metal forming manufacturing processes, such
as punching using a machine press or stamping press, blanking, embossing, bending,
flanging, and coining

7. .
Gear cutting (milling) process:
In gear cutting process, the cutter is form according to the shape of the tooth. The space to be
remove between two adjacent teeth by form milling cutter. The cutter is attached on the
mandrel and connected to dividing head. The selection of cutter is depend upon the size of
gear tooth and number of teeth.

8. Gear Terminology There are several gear and gear-tooth dimensions and terms important to
the understanding of gear production and finishing processes. These terms include:
1. Base Circle: The diameter from which the involute tooth profile is developed.
2. Pitch Circle: The imaginary rolling circle produced by the meshing gears
during rotation. Also known as the Pitch Diameter.
3. Line of Centers: Line connecting the Pitch Circle centers of mating gears.
4. Pitch Point: The point of tangency of two gear Pitch Circles, through the Line
of Centers.
5. Line of Action: A line tangent to the Base Circles of mating gears, through the
Pitch Point and thus the path of tooth contact.
6. Pressure Angle: The angle formed between the Line of Action and a line
tangent to the Pitch Point.
7. Outside Circle: The outside diameter of gear. Also known as the Addendum
Circle.
8. Root Circle: The diameter of the gear at the tooth base. Also known as the
Dedendum Circle.
9. Addendum: The radial distance between the Pitch Circle and the Outside
Circle of the gear.
10. Dedendum: The radial distance between the Pitch Circle and the Root Circle.
11. Tooth Thickness: The thickness of the gear tooth measured along the Pitch
Circle.
12. Circular Pitch: The length of the arc along the Pitch Circle between
corresponding points of adjacent teeth.
13. Face Width: The width of gear tooth measured axially.
14. Tooth Face: The mating surface of a gear tooth between the Outside Circle
and the Pitch Circle.
15. Tooth Flank: The mating surface of a gear tooth measured between the Pitch
Circle and the Root Circle.