The document discusses various topics related to manufacturing technical objects including: - Guiding components which control the motion of moving parts and can provide translational, rotational, or helical motion. - Degrees of freedom which describe the possible independent movements of parts. - Technical drawings including projections, general arrangements, exploded views, details, dimensions, and developments. - Manufacturing processes involving measuring, layout, machining, assembling, and finishing.

1. Manufacturing
Technical Objects
Chapter 12

2. Guiding Controls
 Guiding is a Mechanical Function
performed by any component that controls
the motion of moving parts.
 E.g. The mechanical function of a hinge is
guiding.
 A Guiding Component or Control is a
component whose mechanical function is
to guide the motion of moving parts.
 E.g. What is the guiding component for the
drawer? The wood slats.
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3. Types of Guiding
 Translational Guiding ensures the straight
translational motion of a moving part.
 E.g. a vertical window groove guides motion
 Rotational Guiding ensures the rotational motion
of a moving part.
 E.g. a bicycle wheel hub guides motion
 Helical Guiding ensures the translation motion of
a moving part while it rotates about the same
axis.
 E.g. threaded shank in a vice guides motion
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4. Degrees of Freedom of Movement
 The Degrees of Freedom are the set of
independent movements that are possible
for a given part in a technical object.
 E.g. A door can only rotate around the
hinges – 1 degree freedom
 E.g. A manual transmission gear shift
moves forward/back and left/right – 2
degrees of freedom
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5. Technical Drawing: Projections
 A projection is the representation of a
three-dimensional object on a two-
dimensional surface.
 The most commonly used projections
are:
1. Isometric: the 3 dimensions of the object
in a single drawing.
2. Multiview: 3 views with greater detail
and no distortion: Top, Front, Side
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6. Isometric vs Multi-view Projection
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7. General Arrangement
 A technical drawing representing the
overall appearance on an object:
 multi-view or isometric
 A title block gives important information;
E.g. the scale.
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8. Exploded Views
 An exploded view is a drawing in which
the various parts of the object are
separated from one another;
 It uses:
 all the components
 an isometric projection
 a scale
 a component list
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9. Detail Drawings
 A detail drawing is a drawing specifying
all of the relevant information for
manufacturing a part.
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10. Dimensional Tolerance
 An indicator of the maximum acceptable
difference between a specified
measurement and the actual
measurement on the finished object.
 Part of a Detail Drawing
 E.g. 50 mm 2 mm
50 mm + 2 mm = 52 mm = Maximum
50 mm – 2 mm = 48 mm = Minimum
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11. Functional Dimensioning
 A drawing that specifies the information
required for the object to work.
 E.g. The amount of play or space between
2 parts to allow them to move.
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12. Developments
 The representation of the surface area
required to make a part by bending.
 E.g. the net of a cube;
 E.g. a metal sheet that will be bent.
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13. Diagrammatic Representations
 A simplified representation of an object, a part of
an object, or a system to:
 Show materials
 Show motion
 Show forces.
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14. Symbols of Force & Motion
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15. MANUFACTURING PROCESS
 Manufacturing is a series of operations
resulting in the creation of a technical
object
 The manufacturing process is divided
into 3 (or 5) steps:
1. Measuring & Laying Out
1. Measuring: determining the size or position of
marking.
2. Laying Out: Tracing marks onto a material.
2. Machining
3. Assembling & Finishing
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16. Machining:
Shaping a material into a desired configuration.
Methods of Machining
Cutting: giving a material a desired shape.
Drilling: making holes in a material.
Tapping: forming screw threads inside holes
drilled into a material.
Threading: forming screw threads around a
rod.
Bending: Curving a material into a certain
shape.
Inspecting: measuring parts to specs.
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17. Assembling and Finishing
 Assembling: techniques used to combine parts
of a technical object:
 E.g. nailing, screwing, bonding, riveting, bolting, and
welding.
 Finishing: techniques used to protect and
enhance a technical object:
 E.g. painting, varnishing, staining, and polishing.
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18. Checkup
 Observatory: The Environment
Page 419, Questions 7 to 10
Page 420, Questions 11 to 14