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Liceo Tecnológico Copiapó 

English Department

2009

Technical Drawing Course For high school 

Adapted text by Nicole Uribe O. 

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UNIT 1

INTRODUCTION OF TECHNICAL DRAWING

Technical drawing is the discipline of creating standardized technical drawing by architects, CAD drafters, design

engineers, and related professionals. Technical drawing includes the various fields and technologies

underpinning electronics, which has in turn revolutionized the art with new tools in the form of Computer Aided

Design (CAD).

A technical drawing or engineering drawing is a type of drawing and form of graphic communication, used in the

transforming of an idea into physical form. This type of drawing is used to fully and clearly define requirements

for engineered items, and is usually created in accordance with standardized conventions for layout,

nomenclature, interpretation, appearance (such as typefaces and line styles), size, etc.

The process of creating a technical drawing is called drafting or technical drawing. A person who does drafting is

known as a drafter. In some areas this person may be referred to as a drafting technician, draftsperson, or

drawing can hold many purposes and meanings, while a technical drawing is intended to concisely and clearly

communicate all needed specifications of a created object or objects.

Technical drawing, also known as drafting, refers to the discipline of producing precise illustrations of things in

fields like architecture and engineering. Generally, the term technical drawing pertains to any kind of drawing

fashioned with technical ideas. Good examples of technical drawing are mechanical drawings, charts, and

sketches. Technical drawings are a means of graphic communication, which aims to clearly and concisely

communicate information about transforming technical ideas or concepts into reality. A technical drawing often

contains both a graphic representation of its subject, and dimensions, notes and specifications.

Today the mechanics of the drafting task have been greatly accelerated through the use of computer-aided

design and drafting systems, but regardless of whether a draft is drawn by hand or with computer assistance, th

 field-use-drawing must be reproducible with a version control system to maintain authorized and approvedchanges to the master document (or computer files, the modern analog).

In some fields, particularly electronics, draftsmen are also known by the ambiguous "designer", whose job would

be distinct and separate from the engineers specifying and working out the design details. In short, draftsmen

are communicators that are part of an engineering team charged with producing specialty documentation

packaged as a design, which, following the standards of the field, can be understood by others with the same

training. Technical drawing in perspective is a universal picture language by which ideas and information may be

made readily available for others.

HISTORY

Drawing to communicate technical ideas may predate the written language. The oldest drawing instruments

known, a drawing board inscripted with a temple plan, date from the 3rd millennium BC from the city of Lagash

in Babylon. The ancient Greeks influenced drawing through their work in geometry, and tools such as the

compass and triangles used in engineering were then developed.

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One of few surviving medieval architectural drawing from the period between the fall of the Roman Empire and

the 13th century is the Plan of Saint Gall, a architectural drawing of a monastic compound dating from the early

9th century. The Plan depicts an entire Benedictine monastic compound including churches, houses, stables,

kitchens, workshops, brewery, infirmary, and even a special house for bloodletting. The Plan was never actually

built, and was so named because it was kept at the famous medieval monastery library of the Abbey of St. Gall, 

where it remains to this day.

Design for a Flying Machine, Leonardo da Vinci, 1488.

The beginning of contemporary technical drawing originates from 15th century renaissance artists like the Italian

Architect Filippo Brunelleschi, who in about 1415 demonstrated the geometrical method of perspective, used

today by artists, by painting the outlines of various Florentine buildings onto a mirror. Leonardo da Vinci further

developed perspective and technical drawing, using geometric principles from famous Greek mathematicians lik

Pythagoras of Samos, and Euclid of Alexandria. In the 18th century the mathematician Gaspard Monge

developed descriptive geometry, when designing a complicated fortress in a star shape using orthographic

projection. Early 19th century isometric drawing was introduced by the Englishman William Farish.

Prior to the 18th century there was no need for interchangeable parts, the ability to select components for

assembly at random and fit them together within proper tolerances, and accurate drawings were not necessary.

Inventors, engineers and builders made each product one at a time, and each product was unique. Many design

used through the 19th century were accomplished by first completing a hand sketch of the object to build. Theswere them converted into wooden models from which patterns were constructed. This practice followed well

into the 20th century by some. One of the first efforts to create a program to standardize drawing and establish

mechanical drawing school came from the Franklin Institute in Philadelphia in 1824.

The 18th century architectural practice technical drawing had become the normal medium for design. Architects

were among the first design discipline to make use of conventions of plan, elevation and section in design and

production control. It was the scale of the projects and number of crafts involved that called for a separation

between design and construction. By the time the Industrial revolution began, these architectural conventions

were readily available to engineers.

Since the Industrial Revolution specialized fields of engineering design have developed to meet the needs of 

industry. Military and civil engineering were the first, from which others developed such as mechanical, 

electrical, chemical, aerospace industrial engineering, and many others.

Eventually the development of the computer had a major impact on the methods used to design and create

technical drawings.

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Fields of technical drawing

The field of technical drawing and drafting work is applied in many specialties, such as:

Aeronautical drafters: prepare engineering drawings detailing plans and specifications used in the

manufacture of aircraft, missiles, and related parts.

Architectural drawing : draw architectural and structural features of buildings and other structures. Thes

workers may specialize in a type of structure, such as residential or commercial, or in a kind of material

used, such as reinforced concrete, masonry, steel, or timber. Architectural drawing can includes all

architectural contracts and drawings such as plot plans, floor plans, elevations, sections, details,

schedules, etc., and any architectural drawing that forms a part of the contract documents.

Civil drafters : prepare drawings and topographical and relief maps used in major construction or civil

engineering projects, such as highways, bridges, pipelines, flood control projects, and water and sewage

systems.

Electrical drafters : prepare wiring and layout diagrams used by workers who erect, install, and repair

electrical equipment and wiring in communication centers, power plants, electrical distribution systems,and buildings.

Electronics drafters: draw wiring diagrams, circuit board assembly diagrams, schematics, and layout

drawings used in the manufacture, installation, and repair of electronic devices and components.

Mechanical drafters: prepare drawings showing the detail and assembly of a wide variety of machinery

and mechanical devices, indicating dimensions, fastening methods, and other requirements.

Process piping or pipeline drafters: prepare drawings used in the layout, construction, and operation of 

oil and gas fields, refineries, chemical plants, and process piping systems.

Further, special fields of technical drawings, such as the drawing of gears and cams, welding, riveting, electrical

components and circuits, piping, structures, and mapping and typography have evolved to support the

specialized fields of engineering.

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Types of technical drawings

Construction drawing

Construction drawing of a Machine tool part.

Construction drawing is a type of technical drawing, created within the engineering discipline, and used to fully

and clearly define requirements for engineered items.

Construction drawings are usually created in accordance with standardized conventions for layout,

nomenclature, interpretation, appearance (such as typefaces and line styles), size, etc.

Its purpose is to accurately and unambiguously capture all the geometric features of a product or a component.

The end goal of an engineering drawing is to convey all the required information that will allow a manufacturer

to produce that component.

Cutaway drawings

Cutaway drawing of a Nash 600. 

A cutaway drawing is a technical illustration, in which surface elements three-dimensional models are selectivelyremoving, to make internal features visible, but without sacrificing the outer context entirely.

The purpose of a cutaway drawing is to allow the viewer to have a look into an otherwise solid opaque object.

Instead of letting the inner object shine through the surrounding surface, parts of outside object are simply

removed. This produces a visual appearance as if someone had cutout a piece of the object or sliced it into parts

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Cutaway illustrations avoid ambiguities with respect to spatial ordering, provide a sharp contrast between

foreground and background objects, and facilitate a good understanding of spatial ordering.

Explore view drawing

Gear pump exploded.

An exploded view drawing is a technical drawing of an object that shows the relationship or order of assembly othe various parts. It shows the components of an object slightly separated by distance, or suspended in

surrounding space in the case of a three-dimensional exploded diagram. An object is represented as if there had

been a small controlled explosion emanating from the middle of the object, causing the object's parts to be

separated an equal distance away from their original locations.

An exploded view drawing can show the intended assembly of mechanical or other parts. In mechanical systems

usually the component closest to the center are assembled first, or is the main part in which the other parts get

assembled. This drawing can also help to represent disassembly of parts, where the parts on the outside

normally get removed first.

Patent drawing

Wright brothers Patent drawing, 1908.

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A patent drawing is a technical drawing of a patent invention, that shows the nature of the invention. The

drawing must show every feature of the invention specified in the claims, and is required by the patent office

rules to be in a particular form.

The applicant for a patent will be required by law to furnish a drawing of the invention whenever the nature of 

the case requires a drawing to understand the invention. This drawing must be filed with the application. This

includes practically all inventions except compositions of matter or processes, but a drawing may also be useful

in the case of many processes.

The drawing must show every feature of the invention specified in the claims, and is required by the patent

office rules to be in a particular form. The Office specifies the size of the sheet on which the drawing is made, th

type of paper, the margins, and other details relating to the making of the drawing. The reason for specifying the

standards in detail is that the drawings are printed and published in a uniform style when the patent issues and

the drawings must also be such that they can be readily understood by persons using the patent descriptions.

Technical illustrations

Illustration of a drum set.

Technical illustration is the use of illustration to visually communicate information of a technical nature.

Technical illustrations can be component technical drawings or diagrams. The aim of technical illustration is togenerate expressive images that effectively convey certain information via the visual channel to the human

observer.

The main purpose of technical illustration is to describe or explain these items to a more or less nontechnical

audience. The visual image should be accurate in terms of dimensions and proportions, and should provide an

overall impression of what an object is or does, to enhance the viewer’s interest and understanding. 

Illustrative techniques are often designed in way that even a person with no technical understanding clearly

understands the piece of art. The use of varying line widths to emphasize mass, proximity, and scale helped to

make a simple line drawing more understandable to the lay person. Cross hatching, stippling, and other lowabstraction techniques gave greater depth and dimension to the subject matter.

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Sketch for a government building.

Technical sketches

A sketch is a rapidly executed freehand drawing that is not intended as a finished work. In general, a sketch is a

quick way to record an idea for later use. Architect's sketches primarily serve as a way to try out different ideas

and establish a composition before undertaking a more finished work, especially when the finished work is

expensive and time consuming.

Architectural sketches, for example, are a kind of diagrams. These sketches, like metaphors, are used by

architects as a mean of communication in aiding design collaboration. This tool helps architects to abstract

attributes of hypothetical provisional design solutions and summarizes their complex patters, hereby enhancing

the design process.

Manual drafting

The basic drafting procedure is to place a piece of paper (or other material) on a smooth surface with right-angle

corners and straight sides—typically a drafting table. A sliding straightedge known as a T-square is then placed oone of the sides, allowing it to be slid across the side of the table, and over the surface of the paper.

A drafting table

"Parallel lines" can be drawn simply by moving the T-square and running a pencil or technical pen along the T-

square's edge, but more typically the T-square is used as a tool to hold other devices such as set squares or

triangles. In this case the draftsman places one or more triangles of known angles on the T-square—which is

itself at right angles to the edge of the table—and can then draw lines at any chosen angle to others on the page

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Modern drafting tables (which have by now largely been replaced by CAD workstations) come equipped with a

parallel rule that is supported on both sides of the table to slide over a large piece of paper. Because it is secured

on both sides, lines drawn along the edge are guaranteed to be parallel.

Technical drawing instruments

Size chart with ANSI sizes

Stencils for correct technical writing. 

In addition, the draftsperson uses several tools to draw curves and circles. Primary among these are the

compasses, used for drawing simple arcs and circles, and the: French curve, typically a piece of plastic with

complex curves on it. A spline is a rubber coated articulated metal that can be manually bent to most curves.

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Drafting templates assist the draftsperson with creating recurring objects in a drawing without having to

reproduce the object from scratch every time. This is especially useful when using common symbols; i.e. in the

context of stagecraft, a lighting designer will typically draw from: the USITT standard library of lighting fixture

symbols to indicate the position of a common fixture across multiple positions. Templates are sold commercially

by a number of vendors, usually customized to a specific task, but it is also not uncommon for a draftsperson to

create their own templates.

Basic drafting system

Drawing

type "name"

Dimensions

(width X height)

Drawing

type "name"

Dimensions

(width X height)

A-size 8.5 by 11.0 inches

22 cm by 28 cmB-size 

11.0 by 17.0 inches

28 cm by 43 cm

C-size 17.0 by 22.0 inches

43 cm by 56 cmD-size 

22.0 by 34.0 inches

56 cm by 86 cm

E-size 34.0 by 44.0 inches

86 cm by 112 cmF-size 

44.0 by 68.0 inches

112 cm by 173 cm

G-size 68.0 by 88.0 inches

224 cm by 173 cmH-size 

88.0 by 136 inches

173 cm by 345 cm

As can be seen in the series, the height of the previous drawing

size becomes double the height of the next size in the sequence.

This basic drafting system requires an accurate table and constant attention to the positioning of the tools. A

common error is to allow the triangles to push the top of the T-square down slightly, thereby throwing off all

angles. Even tasks as simple as drawing two angled lines meeting at a point require a number of moves of the T-

square and triangles, and in general drafting can be a time consuming process.

A solution to these problems was the introduction of the mechanical "drafting machine", an application of the

pantograph (sometimes referred to incorrectly as a "pentagraph" in these situations) which allowed the

draftsman to have an accurate right angle at any point on the page quite quickly. These machines often included

the ability to change the angle, thereby removing the need for the triangles as well.

In addition to the mastery of the mechanics of drawing lines, arcs and circles (and text) onto a piece of paper—

with respect to the detailing of physical objects—the drafting effort requires a thorough understanding of 

geometry, trigonometry and spatial comprehension, and in all cases demands precision and accuracy, andattention to detail of high order.

Although drafting is sometimes accomplished by a project engineer, architect—or even by shop personnel such

as a machinist—skilled drafters (and/or designers) usually accomplish the task and are always in demand to som

level.

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Computer Aided Design

An oblique view of a four-cylinder inline crankshaft with pistons.

Today, the mechanics of the drafting task have largely been automated and accelerated through the use of 

Computer Aided Design systems (CAD). Computer-aided design is the use of computer technology to aid in the

design and particularly the drafting of a part or product, including entire buildings. It is both a visual (or drawing

and symbol-based method of communication whose conventions are particular to a specific technical field.

Drafting can be done in two dimensions ("2D") and three dimensions ("3D"). Drafting is the integralcommunication of technical or engineering drawings and is the industrial arts sub-discipline that underlies all

involved technical endeavors. In representing complex, three-dimensional objects in two-dimensional drawings,

these objects have traditionally been represented by three projected views at right angles.

CAD drafters

CAD drafters prepare technical drawings and plans, which are used to build everything from manufactured

products such as toys, toasters, industrial machinery, and spacecraft to structures such as houses, office

buildings, and oil and gas pipelines.

In the past, drafters sat at drawing boards and used pencils, pens, compasses, protractors, triangles, and other

drafting devices to prepare a drawing by hand. Now, most drafters use Computer Aided Design and Drafting

(CADD) systems to prepare drawings. Consequently, some drafters may be referred to as CADD operators.

With CADD systems, drafters can create and store drawings electronically so that they can be viewed, printed, o

programmed directly into automated manufacturing systems. CADD systems also permit drafters to quickly

prepare variations of a design. Although drafters use CADD extensively, it is only a tool. Drafters still need

knowledge of traditional drafting techniques, in addition to CADD skills. Despite the nearly universal use of CADD

systems, manual drafting and sketching are used in certain applications.

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UNIT 2

HOW TO USE AUTO CAD

AutoCAD and AutoCAD LT Interface Overview

The Ribbon

Maximize the area available for work using a compact interface that contains the most commonly used controls

The ribbon can be displayed horizontally across the top of the drawing window, vertically to the left or right of 

the drawing window, or as a floating palette.

The Application Menu

Click the Application button to create, save, audit, recover, or publish a file. You can also perform a real-time

search for commands available on the Quick Access toolbar, in the Application menu, or on the ribbon. The

Application menu also allows you to view, sort, and access supported files you have recently opened.

SteeringWheels

Access navigation tools such as pan, zoom, orbit, rewind, and walk from a single interface. Start the navigation

tools by clicking a wedge or by clicking and dragging the cursor over a wedge. You can access Steering Wheels

from the drawing status bar.

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InfoCenter 

Search for information through keywords or phrases, display the Communication Center panel for product

updates and announcements, or display the Favorites panel to access saved topics. You can also receive

information from RSS feeds, or feeds published by your CAD manager.

Tool Palettes

Organize, share, and place tools onto a tool palette or are provided from third-party developers. Change the

properties of any tool on a tool palette and organize tool palettes into groups.

The Command Prompt

Start a command by entering either the command name or the command alias at the command prompt and

pressing Enter or Spacebar. When Dynamic Input is on and is set to display dynamic prompts, you can enter

many commands in tooltips that are displayed near the cursor.

Model Viewports

Display multiple views of the same drawing. Add or remove viewports using the VPORTS command, or from the

ribbon on the View tab in the Viewports panel.

Status Bar

View the coordinate values of your cursor, and access several buttons for turning drawing tools on and off, as

well as several display tools used to scale annotations.

ShowMotion 

Access named views that are organized into animated sequences within the current drawing. You can access

ShowMotion from the drawing status bar.

ViewCube

When the cursor is positioned over the ViewCube tool, it becomes active; you can switch to one of the available

preset views, roll the current view, or change to the Home view of the model. You can access the ViewCube from

the drawing status bar.

Quick Access Toolbar

Access frequently used commands such as New, Open, Save, Plot, Undo, and Redo from the Quick Access oolbar

Add commands to the Quick Access toolbar using the shortcut menus of all commands on the ribbon, applicatio

menu, and toolbars.

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Action Recorder

Automate repetitive drafting and editing tasks by recording action macros. Use most of the commands and user

interface elements that are available in AutoCAD to create your action macro and then save it. You can find the

Action Recorder on the ribbon's Manage tab.

Menus, Toolbars, and Tool Palettes

You can use several menus, shortcut menus, tool palettes, and toolbars for access to frequently used commands

settings, and modes.

Tool Palettes 

Tool palettes are tabbed areas within the Tool Palettes window that provide an efficient method for

organizing, sharing, and placing blocks and hatches. Tool palettes can also contain custom tools provided

by third-party developers.

Tool palettes are tabbed areas within the Tool Palettes window that provide an efficient method for organizing,

sharing, and placing blocks and hatches. Tool palettes can also contain custom tools provided by third-partydevelopers.

Create and Use Tools from Objects and Images

You can create a tool by dragging objects from your drawing onto a tool palette. You can then use the

new tool to create objects with the same properties as the object you dragged onto the tool palette.

Create and Use Tools from Objects and Images

You can create a tool by dragging objects from your drawing onto a tool palette. You can then use the new tool

to create objects with the same properties as the object you dragged onto the tool palette.

Tool palettes are tabbed areas within the Tool Palettes window. The items you add to a tool palette are called

tools. You can create a tool by dragging any of the following, one at a time, onto your tool palette:

Geometric objects such as lines, circles, and polylines

Dimensions

Blocks

Hatches

Solid fills

Gradient fills

Raster imagesExternal references (xrefs)

You can then use the new tool to create objects in your drawing with the same properties as the object you

dragged to the tool palette. For example, if you drag a red circle with a lineweight of .05 mm from your drawing

to your tool palette, the new tool creates a red circle with a lineweight of .05 mm. If you drag a block or xref to a

tool palette, the new tool inserts the block or xref with the same properties into your drawing.

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When you drag a geometric object or a dimension onto a tool palette, the new tool is automatically created with

an appropriate flyout. Dimension tool flyouts, for example, provide an assortment of dimension styles. Click the

arrow on the right side of the tool icon on the tool palette to display the flyout. When you use a tool on a flyout,

the object in the drawing will have the same properties as the original tool on the tool palette.

For block and xref tools, you can choose to be prompted at the command line for a rotation angle (starting from

0) when you click and place the block or xref. When you select this option, the angle that is specified under

Rotation in the Tool Properties dialog box is ignored. The prompt for a rotation angle is not shown if you drag th

block or xref or, if at the initial insertion command line prompt, you enter rotate.

Blocks that are placed by dragging from a tool palette must often be rotated or scaled after they are placed. You

can use object snaps when dragging blocks from a tool palette; however, grid snap is suppressed during dragging

You can set an auxiliary scale for a block or a hatch tool to override the regular scale setting when the tool is

used. (An auxiliary scale multiplies your current scale setting by the plot scale or the dimension scale.)

Scale Blocks Automatically

When a block is dragged from a tool palette into a drawing, it is scaled automatically according to the ratio of 

units defined in the block and defined in the current drawing. For example, if the current drawing uses meters as

its units and a block is defined using centimeters as its units, the ratio of the units is 1 m/100 cm. When the bloc

is dragged into the drawing, it is inserted at 1/100 scale.

Note In the Options dialog box, User Preferences tab, the Source Content Units and Target Drawing Units setting

are used when Drag-and-Drop Scale is set to Unitless, either in the source block or target drawing.

Create and Use Command ToolsYou can create a tool on a tool palette that executes a single command or a string of commands.

You can add frequently used commands to a tool palette. When the Customize dialog box is open, you

can drag tools from a toolbar to a tool palette.

Once you add a command to a tool palette, you can click the tool to execute the command. For example,

clicking a Save tool on a tool palette saves a drawing just as the Save button on the Standard toolbar

does.

You can also create a tool that executes a string of commands or customized commands, such as an

AutoLISP®

routine, a VBA macro or application, or a script.

Change Tool Palette Settings

The options and settings for tool palettes are accessible from shortcut menus that are displayed when

you right-click in different areas of the Tool Palettes window.

The options and settings for tool palettes are accessible from shortcut menus that are displayed when you right-

click in different areas of the Tool Palettes window.

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These settings include

Auto-hide. The Tool Palettes window can automatically roll open or roll away (called rollover behavior)

when your cursor moves over the title bar on the Tool Palettes window.

Transparency. The Tool Palettes window can be made transparent so it does not obscure objects under it

Views. The display style and size of the icons in a tool palette can be changed.

You can dock the Tool Palettes window on the right or left edge of the application window. Press the CTRL key if

you want to prevent docking as you move the Tool Palettes window.

Tool palette settings are saved with your profile.

Control Tool Properties

You can change the properties of any tool on a tool palette.

Once a tool is on a tool palette, you can change its properties. For example, you can change the insertion scale o

a block or the angle of a hatch pattern.

To change tool properties, right-click on a tool, and then click Properties on the shortcut menu to display the

Tool Properties dialog box. The Tool Properties dialog box has the following two categories of properties:

Insert or Pattern properties. Control object-specific properties such as scale, rotation, and angle.

General properties. Override the current drawing property settings such as layer, color, and linetype.

You can expand and collapse the property categories by clicking the arrow buttons.

Update the Icon for a Tool

The icon for a block, xref, or raster image in a tool palette is not automatically updated if its definition changes.

you change the definition for a block, xref, or raster image, you can update the icon by right-clicking the tool in

the palette and selecting Update Tool Image. You must save the drawing before you can update the tool image.

Alternatively, you can delete the tool, and then replace it using DesignCenter™

.

Specify Overrides for Tool Properties

In some cases, you may want to assign specific property overrides to a tool. For example, you may want a hatch

to be placed automatically on a pre-specified layer, regardless of the current layer setting. This feature can save

you time and reduce errors by setting properties automatically when creating certain objects.

The Tool Properties dialog box provides areas for each possible property override.

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Layer property overrides affect color, linetype, lineweight, plot style, and plot. Layer property overrides are

resolved as follows:

If a layer is missing from the drawing, that layer is created automatically.

If a layer to which you are adding content is currently turned off or frozen, the layer is temporarily turned on or

thawed.

Customize Tool Palettes

You can add tools to a tool palette with several methods.

You can add tools to a tool palette with several methods.

You can create new tool palettes using the Properties button on the title bar of the Tool Palettes window. Add

tools to a tool palette with the following methods:

Drag any of the following onto your tool palette: geometric objects such as lines, circles, and polylines; dimensions

hatches; gradient fills; blocks; xrefs; raster images.

Drag drawings, blocks, and hatches from DesignCenter to the tool palette. Drawings that are added to a toolpalette are inserted as blocks when dragged into the drawing.

Using the Customize dialog box, drag commands to a tool palette just as you might add them to a toolbar.

Use Cut, Copy, and Paste to move or copy tools from one tool palette to another.

Create a tool palette tab with predetermined content by right-clicking a folder, a drawing file, or a block in the

DesignCenter tree view, and then clicking Create Tool Palette on the shortcut menu.

Note If the source drawing file for a block, xref, or raster image tool is moved to a different folder, you must

modify the tool that references it by right-clicking the tool and, in the Tool Properties dialog box, specifying the

new source file folder.

Once tools are placed on a tool palette, you can rearrange them by dragging them around or by sorting them.

You can also add text and separator lines to tool palettes.

You can move a tool palette tab up and down the list of tabs by using the tool palette shortcut menu or the Tool

Palettes tab of the Customize dialog box. Similarly, you can delete tool palettes that you no longer need. Tool

palettes that are deleted are lost unless they are first saved by exporting them to a file. You can control the path

to your tool palettes on the Files tab in the Options dialog box. This path can be to a shared network location.

Read-Only Tool Palettes

If a tool palette file is set with a read-only attribute, a lock icon is displayed in a lower corner of the tool palette.

This indicates that you cannot modify the tool palette beyond changing its display settings and rearranging the

icons.

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To apply a read-only attribute to a tool palette, right-click the tool palette (ATC) files in the following location:

C:\documents and settings\<user name>\application data\Autodesk\AutoCAD 2006\r16.2\menu\support\Tool

Palette\Palettes. On the shortcut menu, click Properties. On the General tab, select Read-only, and click OK.

Organize Tool Palettes

You can organize tool palettes into groups and specify which group of tool palettes is displayed.For example, if you have several tool palettes that contain hatch patterns, you can create a group called

Hatch Patterns. You can then add all your tool palettes that contain hatch patterns to the Hatch Pattern

group. When you set the Hatch Pattern group as the current group, only those tool palettes you’ve added

to the group are displayed.

Save and Share Tool Palettes

Save and share a tool palette by exporting it or importing it as a tool palette file.

Save and share a tool palette by exporting it or importing it as a tool palette file.

You can save and share a tool palette by exporting it or importing it as a tool palette file. You import and export

tool palette from the Tool Palettes tab of the Customize dialog box. Tool palette files have an .xtp file extension.

Tool palettes can be used only in the version of AutoCAD in which they were created. For example, you cannot

use a tool palette that was created in AutoCAD 2006 in AutoCAD 2005.

The default path for tool palette files is set on the Files tab of the Options dialog box under Tool Palettes File

Locations.

Tool palette groups are saved in profiles.

If you send tool palettes to someone who uses AutoCAD LT, note that some tools created in AutoCAD do not

behave the same way or work in AutoCAD LT. Note the following limitations:

The color property of tools that use a color other than an AutoCAD Color Index (ACI) color convert to

ByLayer in AutoCAD LT.

Gradient fill tools switch to hatch tools in AutoCAD LT.

Raster image tools do not work in AutoCAD LT.

Note if a tool palette file is set with a read-only attribute, a lock icon is displayed in a lower corner of the toolpalette. This indicates that you cannot modify the tool palette beyond changing its display settings and

rearranging the icons.

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Toolbars 

Use buttons on toolbars to start commands, display flyout toolbars, and display tooltips. You can display

or hide, dock, and resize toolbars.

Toolbars contain buttons that start commands. When you move your mouse or pointing device over a toolbar

button, the tooltip displays the name of the button. Buttons with a small black triangle in the lower-right corner

are flyout toolbars that contain related commands. With the cursor over the icon, hold down the left button on

your mouse until the flyout toolbar is displayed.

The Standard toolbar at the top of the drawing area is displayed by default. This toolbar is similar to those found

in Microsoft®

Office programs. It contains frequently used AutoCAD commands such as PROPERTIES, PAN, and

ZOOM, as well as Microsoft Office standard commands such as New, Open, and Save.

Display or Hide, Dock, and Resize Toolbars

AutoCAD initially displays several toolbars:

Standard toolbar

Styles toolbarLayers toolbar

Properties toolbar

Draw toolbar

Modify toolbar

You can display or hide these toolbars and additional ones. You can also create your own toolbars.

A toolbar can be floating or docked. A floating toolbar is located anywhere in the drawing area, and you can drag

a floating toolbar to a new location, resize it, or dock it. A docked toolbar is attached to any edge of the drawing

area. You can move a docked toolbar by dragging it to a new docking location.

The Menu Bar 

Display pull-down menus from the menu bar using one of several methods. You can also specify alternat

menus.

Menus are available from the menu bar at the top of the AutoCAD drawing area.

You can specify menus to display in the program by customizing a CUI file and loading it into the program

Shortcut Menus 

Display a shortcut menu for quick access to commands that are relevant to your current activity.

Display a shortcut menu for quick access to commands that are relevant to your current activity.

You can display different shortcut menus when you right-click different areas of the screen, including

Within the drawing area with or without any objects selected

Within the drawing area during a command

Within the text and command windows

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Within areas and on icons in DesignCenter

Within areas and on text in the In-Place Text Editor

On a toolbar or tool palette

On the Model or layout tabs

On the status bar or the status bar buttons

In certain dialog boxes

Shortcut menus typically include options to

Repeat the last command entered

Cancel the current command

Display a list of recent user input

Cut, copy, and paste from the Clipboard

Select a different command option

Display a dialog box, such as Options or Customize

Undo the last command entered

You can customize right-click behavior to be time-sensitive, so that a quick right-click acts the same as pressing

ENTER, and a longer right-click displays a shortcut menu.

Shortcut menus can be customized using a customization (CUI) file. The main CUI file is called acad.cui by defaul

The Object Snap Menu 

Specify an object snap quickly and conveniently from a shortcut menu.

The object snap menu is displayed at your cursor location when you hold down SHIFT and click the right

mouse button or the equivalent button on another pointing device.

The default object snap menu lists object snaps and tracking options. If you want to change the options,

you can modify a customization file. The main customization file that’s shipped with the product is

acad.cui.

Create Your Own Menu and Toolbar GroupsCreate your own menu and toolbar groups in a workspace.

You can identify task specific toolbars and menus for each workspace that you create or use.

For more information about how toolbars and menus interact with workspaces, see Use Workspaces and

Customize Workspaces in the Customization Guide.

Commands

COPYCLIP Copies objects or command line text to the Clipboard

COPYHIST Copies the text in the command line history to the Clipboard

CUSTOMIZE Customizes tool palettes

CUTCLIP Copies objects to the Clipboard and removes the objects from the drawing

MENULOAD Loads partial menu files

MENUUNLOAD Unloads partial customizaiton files

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OPTIONS Customizes the program settings

OSNAP Sets running object snap modes

PAN Moves the view in the current viewport

PASTECLIP Inserts data from the Clipboard

PROPERTIES Controls properties of existing objects

TOOLPALETTES Opens the Tool Palettes window

TOOLPALETTESCLOSE Closes the Tool Palettes window

TRAYSETTINGS Controls the display of icons and notifications in the status bar trayU Reverses the most recent operation

UNITS Controls coordinate and angle display formats and precision

WORKSPACE Creates, modifies, and saves workspaces and makes a workspace current

ZOOM Increases or decreases the apparent size of objects in the current viewport

System Variables

CMDINPUTHISTORYMAXSets the maximum number of previous input values that are stored for a prompt in a

command

INPUTHISTORYMODE Controls the content and location of the display of a history of user input

INSUNITSDEFSOURCE Sets source content units value when INSUNITS is set to 0

INSUNITSDEFTARGET Sets target drawing units value when INSUNITS is set to 0

PALETTEOPAQUE Controls whether windows can be made transparent

PICKFIRSTControls whether you select objects before (noun-verb selection) or after you issue a

command

SHORTCUTMENUControls whether Default, Edit, and Command mode shortcut menus are available in th

drawing area

TOOLTIPS Controls the display of tooltips

TPSTATE Determines whether the Tool Palettes window is active or not

TRAYICONS Controls whether a tray is displayed on the status bar

TRAYNOTIFY Controls whether service notifications are displayed in the status bar tray

TRAYTIMEOUT Controls the length of time (in seconds) that service notifications are displayed

Commands

CUSTOMIZE Customizes tool palettes

TOOLPALETTES Opens the Tool Palettes window

TOOLPALETTESCLOSECloses the Tool Palettes window

UNITS Controls coordinate and angle display formats and precision

System Variables

INSUNITSDEFSOURCESets source content units value when INSUNITS is set to 0INSUNITSDEFTARGET Sets target drawing units value when INSUNITS is set to 0

PALETTEOPAQUE Controls whether windows can be made transparent

TPSTATE Determines whether the Tool Palettes window is active or not

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UNIT 3

DESIGN

An Overview of the Design Process

Design

Design is the process by which the needs of the customer or the marketplace are transformed into a product satisfyingthese needs. It is usually carried out a designer or engineer but requires help from other people in the company.

Design essentially is an exercise in problem solving. Typically, the design of a new product consists of the

following stages:

The development of a new product may also require the development of a prototype to prove that newtechnologies work before committing resources to full-scale manufacture.

The traditional view of the design to manufacture process is that it is a sequential process; the outcome of one

stage is passed on to the next stage. This tends to lead to iteration in the design. I.e. having to go back to an

earlier stage to correct mistakes. This can make products more expensive and delivered to the marketplace late

A better approach is for the designer to consider the stages following design to try and eliminate any potential

problems. This means that the designer requires help from the other experts in the company for example the

manufacturing expert to help ensure that any designs the designer comes up with can be made.

So what factors might a designer have to consider in order eliminating iteration?

Manufacture - Can the product be made with our facilities?

Sales - Are we producing a product that the customer wants?

Purchasing - Are the parts specified in stock, or do why have to order them?

Cost - Is the design going to cost too much to make?

Transport - Is the product the right size for the method of transporting?

Disposal - How will the product be disposed at the end of its life?

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Design Brief 

The design brief is typically a statement of intent. I.e. "We will design and make a Formula One racing car". Although it

states the problem, it isn't enough information with which to start designing.

Product Design Specification (PDS)

This is possibly the most important stage of the design process and yet one of the least understood stage. It is important

that before you produce a 'solution' there is a true understanding of the actual problem. The PDS is a document listing the

problem in detail. It is important to work with the customer and analyse the marketplace to produce a list of requirements

necessary to produce a successful product. The designer should constantly refer back to this document to ensure designs

are appropriate.

To produce the PDS it is likely that you will have to research the problem and analyse competing products and a

important points and discoveries should be included in your PDS.

Concept Design

Using the PDS as the basis, the designer attempts to produce an outline of a solution. A conceptual design is a usually an

outline of key components and their arrangement with the details of the design left for a later stage. For example, a

concept design for a car might consist of a sketch showing a car with four wheels and the engine mounted at the front of 

the car. The exact details of the components such as the diameter of the wheels or the size of the engine are determined a

the detail design stage. However, the degree of detail generated at the conceptual design stage will vary depending on the

product being designed.

It is important when designing a product that you not only consider the product design specification but you also

consider the activities downstream of the design stage. Downstream activities typically are manufacture, sales,

transportation etc. By considering these stages early, you can eliminate problems that may occur at these stages

This stage of the design involves drawing up a number of different viable concept designs which satisfy the

requirements of the product outlined in the PDS and then evaluating them to decide on the most suitable to

develop further. Hence, concept design can be seen as a two-stage process of concept generation and concept

evaluation

Concept generation

Typically, designers capture their ideas by sketching them on paper. Annotation helps identify key points so that their idea

can be communicated with other members of the company.

There are a number of techniques available to the designer to aid the development of new concepts. One of the

most popular is brainstorming.

This technique involves generating ideas, typically in small groups, by saying any idea that comes into your head

no matter how silly it may seem. This usually sparks ideas from other team members. By the end of a

brainstorming session there will be a list of ideas, most useless, but some may have the potential to be

developed into a concept. Brainstorming works better if the members of the team have different areas of 

expertise.

Concept evaluation

Once a suitable number of concepts have been generated, it is necessary to choose the design most suitable for to fulfil th

requirements set out in the PDS. The product design specification should be used as the basis of any decision being made.

Ideally a multifunction design team should perform this task so that each concept can be evaluated from a number of 

angles or perspectives. The chosen concept will be developed in detail.

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One useful technique for evaluating concepts to decide on which one is the best is to use a technique called

'matrix evaluation'

With matrix evaluation a table is produced listing important the features required from a product - usually this

list is drawn up from the important features described in the product design specification. The products are liste

across the table. The first concept is the benchmark concept. The quality of the other concepts are compared

against the benchmark concept for the required features, to help identify if the concept is better, worse than, or

is the same as the benchmark concept. The design with the most 'better than' is likely to be the best concept to

develop further.

Most people who use the matrix technique will assign points, rather than simple, better, worse, same, so that it

is easier to identify which concepts are the best. It is also likely that some features of the design will be more

important than others so a weighting is used.

Detail design

In this stage of the design process, the chosen concept design is designed in detailed with all the dimensions and

specifications necessary to make the design specified on a detailed drawing of the design.

It may be necessary to produce prototypes to test ideas at this stage. The designer should also work closely with

manufacture to ensure that the product can be made.

The function of the PDS

Before we consider exactly what a Product Design Specification (PDS) is, let's spend five minutes on a short

design project.

Design Brief 

A customer has approached us and asked us to produce a design for a chair for their

son.

Read the design brief above and spend five minutes producing a design that you feels fulfils the brief. When you

are happy click on the forward arrow.

Function of the PDS

As we have just seen, it is very easy to misinterpret a design brief and design a product the customer doesn't

want. The aim of the product design specification or PDS as it is also known, is to help you to gain an

understanding of the nature of the problem so that you can design a better solution to the problem.

Going back to our example, it was important for instance to find out the type of chair the customer wanted

before we produced a design. But there are other factors to be considered such as materials available, the size o

the user, or even the colour they customer wants the product to be. The more we know about the problem the

easier it will be to produce a final design that works first time and doesn't require alterations at a later stage.

The product design specification will help you understand the problem before you start your design.

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How to write a PDS

The product design specification (PDS) is a very important document in the design process as it contains all the

information necessary for a design team to successfully produce a solution to the design problem. A PDS splits

the problem up into smaller categories to make it easier to consider the problem. The final document should

fully document as unambiguously as possible all the requirements that a product must fulfil together with any

constraints that may affect the product. The actual or intended customer should be consulted as fully as possible

while the PDS is being drawn up as their requirements are of paramount importance.

Any numeric properties in the PDS should be specified as exactly as possible together with any tolerances

allowed on their value.

Common categories

Various aspects relating to the product must be considered. The actual categories can vary, but a typical PDS ma

consist of the following categories:

Appearance Competition Customer

Documentation  Ergonomics Environment

Installation Product disposal Lead times

Legal and safety

implications

Legislation, patents and

copyrightMaintenance

Materials Packaging and transport Performance

Processes Product cost Product dimensions

Product life Quality Quantity

Standards TestingClick on a category to find out more

information. 

The final document will be agreed by the customer.

Example Product Design Specification

Design Specification for a Portable Winch

The following example PDS, although longer than the PDS's you will produce for your projects, contains many

aspects of a commercial PDS and was written with advice from a winch design company. A real design brief for a

winch would contain many more aspects than outlined here. A PDS for family motor car for example, would hav

many more categories specific to the product and would require several large manuals to list the 'problem' in

detail.

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Portable Winch

Design Brief 

From internal market research, it has been decided that IWC need to design a general purpose winch to sell to

the cable and pipe laying market sector. The winch should be portable but have mounting points for the end

user. It is important that the winch sits within out current range of 'Excel General Purpose winches'.

Performance

1.1 Lift / lower a load of 2.5 tones (+/- 10%).

1.2 Draw in cable in at a rate of 0.2 m/s.

1.3 The winch drive should cut out when the load exceeds 10% of the specified load.

1.4 Drive to stop lowering load when only 1.5 metres of cable remains on winch drum.

1.5 Winch should operate with forward, reverse, stop and inch facility.

1.6 Any braking system employed, should produce a braking torque of 150% the full load torque.

1.7 Winch should have a manual device to control the brake release and load descent in the event of a power

failure.

1.8 In the event of the winch 'overrunning', manual safeties relay/braking device should operate within 1 second

or before the load exceeds a speed of 3m/s.

1.9 The product should be portable but with the option for permanent mounting.

1.10 The product must use a portable power source, preferably a diesel engine.

1.11 The weight of the product must be sufficient to aid the stability of the product.

1.12 Efficiency of the unit should be high, preferably in the area of 20 - 30%.

1.13 The drum should hold 50m of cable.

2.0 Environment

2.1 The winch drive and power unit should be power unit.

2.2 The unit will be mainly used in European weather conditions. But we could expect sales of about 2% unit

volume to the Far East.

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2.3 Temperature ranges:

-28 degree C - European

12 - 44 degree C - Far East

2.4 The product may experience humid conditions.

2.5 Corrosion resistance may be considered by the use of special materials or surface protection methods.

2.6 Any noise from the equipment should not exceed 95 dB at a distance of 1.0m.

2.7 The winch will be stored in suppliers warehouses before sales.

3.0 Product Life Span

3.1 Product will be on the market for 10 years.

3.2 Spare parts will be available for a further 5 years after that.

4.0 Life in Service

4.1 Should withstand an operating period of 1 hr uninterrupted use per day for 5 years.

4.2 Life in service should be assessed against the criteria outlined in the Performance and Environment

categories.

5.0 Shelf Life

5.1 The product will be stored on-site for up to 1 month before dispatched.

5.2 Our Far East distributor may store the product for several months.

6.0 Target Costs

6.1 The product should have an end-user cost of £5500 within Britain.

6.2 The cost of manufacture should be less than £2750.

6.3 The cost of packaging and shipping should be no more than 15% of the manufacturing cost.

7.0 Quantity

7.1 150 units in the first year, increasing to 800 within four years.

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8.0 Maintenance

8.1 To be maintenance free except for light lubrication once a month and a recommended service every two

years.

8.2 Parts requiring lubrication should be accessible within 15 minutes without the use of special tools or

equipment.

8.3 All fasteners used should comply with BS6105.

8.4 Spares should be available for 5 years after the product is replaced with a new model.

8.5 No special tools should be required for maintenance.

9.0 Marketing

9.1 Initially to be manufactured for the European market but our Far Eastern distributors in Singapore, Hong

Kong and Australia will be able to find a market for the product.

9.2 The winch should be operating against equivalent models which include the following companies:

Swansom - England

Oholom - Sweden

Winderhock - Germany

9.3 Applicable markets:

Telecom - Cable laying

Gas and Electricity operators

Pipe laying services

Civil Engineering Operations

9.4 Summary of market requirements:

Portable winch which can be attached to vans and low loaders

Use portable power source

To be used in all weather

To allow one man operation

To have at least 40m of cable

To pull 2000kg

10.0 Packaging

10.1 Packaging / transport cost should be kept to a minimum and preferably below 5% of the unit cost.

11.0 Size and Weight Restrictions

11.1 Weight should not exceed 500 kg.

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11.2 Length not to exceed 2500 mm.

11.3 Width not to exceed 2000mm.

11.4 Height not to exceed 2000mm.

12.0 Shipping

12.1 Product will be shipped by road within Europe.

12.2 Product will be shipped by sea to Far Eastern markets.

13.0 Manufacturing Processes

13.1 Capacity is available for current market demand within scope to increase production to 200 per year

without investment / expansion.

13.2 Motors, transmissions, bearing and ropes are bought in from the following suppliers:

Drives: 

Electric Motors - Brook Compton

Diesel Engines - Gardener

Hydraulic Motors - Hydrostatic Transmission Ltd

Bearings: 

RHP Bearings

Transmissions: 

Couplings - Wellman Bibby

Worm Gears - Reynold

Planetary Gears - David Brown (PPG Divisions)

In-Line Gears - David Brown Radicon Ltd

V-belts - Fenner

Ropes: 

Bridon

13.3 Castings and injection moulds produced by external suppliers.

14.0 Aesthetics

14.1 The form can follow function.

14.2 If cost dictates, the winch should look attractive to improve our perception within the market.

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15.0 Ergonomics

15.1 Controls to be mounted in an accessible position, relative to the operator i.e. waist height - around 1m, to

accommodate 95% of the working population.

15.2 All controls should be hand operated, requiring one-hand operation with a maximum force of 1.5 N/m2

15.3 One man should be able to operate the product.

16.0 Customer Requirements

See Marketing 

17.0 Competition

17.1 The winch will be operating against equivalent models which include the following companies:

Swansom - England

Oholom - Sweden

Winderhock - Germany

18.0 Quality and Reliability

18.1 Quality should be such that winches should not generally fail within a period of three years and only 1 in 50

should fail within the first year.

18.2 No winch should fail in the area of the safety overload device.

19.0 Standards and Specifications

19.1 Standards to be adhered to:

BS 5000 part 99 Motor Performance

BS 6105 and BSEN 20898(1) Bolts

BS 6322(2) & BS 4320 Nuts and washers

BS 7676 and BS 4517 Gears

BS 3019 Welding

BS 5989 Bearings

BS 2754 Electrical Insulation

BS 5646 pt4 Bearing Housing

BS 4235 Keys and Keyways

BS 7664 PaintingBS 1399 Seals

20.0 Company Constraints

20.1 None - except those outlines in Manufacturing and Processes.

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21.0 Processes

21.1 All components to be of metric form and comply with ISO 4900 for limits and fits.

22.0 Safety

22.1 No winch should fail in the area of the safety overload device.

22.2 Winch should not operate when maintenance is being carried out.

23.0 Testing

23.1 Testing is to be carried out on 5% of units.

23.2 All cables should be tested to BS3621.

24.0 Legal

24.0 Possible litigation lies in the user injuring themselves by having access to moving parts during winch

operation.

25.0 Installation

N/A

26.0 Documentation

26.1 Product should be supplied with a user manual covering winch operation and maintenance.

26.2 Suppliers require maintenance and repair manual.

27.0 Disposal

27.1 Plastic parts should be separable and marked to aid disposal.

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UNIT 4

DRAWING SKILLS

Graphics Skills

Drawing in 3D 

Covers some of the more common 3D systems which can be used to make your drawings look more realistic

Improving your sketching skills 

Engineering Drawing 

Covers some of the basic rules for engineering drawing such as: dimensioning, sectioning, etc.

Introduction to 3 Dimensional graphics

Representing 3 dimensions on a flat piece of paper is a very important skill for designers

enabling them to communicate their ideas to other people. This is especially useful when

showing your design to non designers such as managers and marketing personnel.

There are several tried and tested 3 Dimensional drawing systems used to produce a

realistic representation of an object. Some techniques such as isometric are based on

mathematical systems, others a try to convey a larger degree of realism by applying

perspective to the drawing. Amongst the methods covered in this tutorial are oblique,

isometric, axonometric, and perspective drawing techniques.

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Oblique

Isometric

Drawing a box in isometric.

Drawing shapes other than cubes

Drawing circles in isometric

Axonometric

Drawing 'holes' and cavities in

objects

Perspective

One Point Perspective

Constructing a box in one point perspective

Two point perspective

Constructing circles in perspective

Drawing Cylinders in perspective

Constructing a grid (1)Constructing a grid (2)

Using a grid

Three point perspective 

Oblique

Oblique drawing is the

crudest '3D' drawing method

but the easiest to master.

Oblique is not really a '3D'

system but a 2 dimensional

view of an object with

'forced depth'.

When using oblique the side

of the object you are looking

at is drawn in two

dimensions, i.e. flat. The

other sides are drawn in at

45 degrees but instead of drawing the sides full size

they are only drawn with

half the depth creating

'forced depth' adding an

element of realism to the

object.

Even with this 'forced

depth', oblique drawings

look very unconvincing to

the eye. For this reason

oblique is rarely used by

professional designer and

engineers.

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How to draw an object using oblique

When drawing an object in

oblique, the front view of the

object is drawn flat

Oblique with 'foreshortening'

The side views are drawn in

at a 45 degree angle.

Standard practice is to

'foreshorten' the side views

to provide a more convincing

view of an object. To

foreshorten the side views,

the objects side

measurements are halved. In

this case, the sides are 50

mm long, but they have

been drawn in at 25 mm.

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Oblique with no

'foreshortening

This view is drawn at fullsize. Notice how circle looks

elongated

Isometric

Isometric is a mathematical method of constructing a 3

dimensional object without using perspective. Isometricwas an attempt to make drawings more realistic.

The mathematics involved mean that all lengths when

drawn at 30 degrees can be drawn using their true length

(in other words lines aren't shortened as with oblique

drawings).

An isometric drawing shows two sides of the object and the

top or bottom of the object. All vertical lines are drawn

vertically, but all horizontal lines are drawn at 30 degrees tothe horizontal. Isometric is an easy method of constructing

a reasonable '3 dimensional' images.

Drawing a box in isometric

To draw in isometric you will need a 30

/ 60 degree set square (As illustrated).

These can be purchased from all major

stationary stores.

The steps below demonstrate how todraw a 5cm3 box in isometric.

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Drawing a box in isometric

1. Draw the front vertical edge of the cube. 2. The sides of the box are drawn at 30

degrees to the horizontal to the required

length.

Note: All lengths are drawn as actuallengths in standard isometric.

3. Draw in the back verticals.  4. Drawn in top view with all lines drawn 30

degrees to the horizontal.

Drawing more complicated shapes

Initially when you first start using isometric it can be useful to use a simple box as

a basic building block a guide to help you draw more complicated shapes. 

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This simple example shows

you how you can use a box

to help you accurately draw

a more complicated shape.

The object we are going to

draw is L-shaped as

illustrated by the

engineering drawing (left).

Outline of 'guide box' 

The first step is to draw our

guide box. This box is the

size of the maximum

dimensions. In this case, 50mm long, 25 mm wide and

50 mm high.

Draw the box in very lightly.

When we have the final

shape we can darken the

lines.

To get the L-shape we need

remove an area from this

box.

Draw a box 40 x 10 x 50 mm,

the shape that needs to be

removed from the box to

create the shape we require.

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The finished shape

Draw in the outline of the

object using a heavier line.

Using this technique you can

draw complex shapes

accurately because you can

use the guide box as a

means to measure your

engineering drawing views.

Drawing circles in isometric

Circles in isometric don't appear circular. Instead they are skewed and are actually elliptical. There are several

methods of constructing circles in isometric. By far the easiest method is to use an isometric circle template

which can be bought from most good art shops. These templates contain a number of isometric circles of variou

sizes.

If you decide not to buy a template then you must construct a circle.

Constructing an isometric circle

1. First draw an isometric square. Draw in the

diagonals, a vertical and a line at 30 degrees

from the midpoint of the sides as illustrated.

2. Place your compass point on the

intersection of the horizontal line and the

vertical line. Draw in a circle which touches

the edges of the box

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3. To draw the next section of the isometric

circle place your compass point on the corner

of the isometric 'square' and draw in the arc

as illustrated.

4. Complete the circle using the appropriate

techniques.

Axonometric

Axonometric or planometric as it is

sometimes known is a method of 

drawing a plan view with a third

dimension. It is used by interior

designers, architects and landscape

gardeners.

Axonometric works by drawing a plan

view at a 45 degree angle with the

depth added vertically. All lengths are

drawn as their true lengths unlike

when you use oblique. This gives the

impression that you are viewing the

objects from above. One advantage of 

axonometric is that circles drawn on

the top faces of objects can be drawn

as a normal circle.

Perspective

All objects we look at have perspective. Objects closer to us are bigger than objects further

away. In other words as objects get further away they seem to 'vanish into the distance'.

The ability to produce good sketches with convincing perspective is an important skill to

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master helping you to visualise your ideas. There are many ways to gain these skills.

Practicing drawing objects can help you see how perspective works and will help you with

freehand sketches. But this will take time.

What we need are methods of constructing objects in using a reliable system. There are

three main perspective systems which allow you to construct an object using a ruler.

One point perspective

Two point perspectiveThree point perspective

One Point Perspective

Using one perspective, parallel lines converge to one point somewhere in the distance. This

point is called the vanishing point (VP). This gives objects an impression of depth.

When drawing using one point perspective all objects vanish to one common point

somewhere on the horizon.

The sides of an object diminish towards the vanishing point. All vertical and horizontal lines

though are drawn with no perspective. i.e. face on.

One point perspective though is of only limited use, the main problem being that theperspective is too pronounced for small products making them looking bigger than they

actually are.

So when would you use one point perspective?

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One area where one point perspective can be quite useful is for sketching room layouts.

Although it is possible to sketch products in one point perspective, the perspective is tooaggressive on the eye making products look bigger than they actually are.

Constructing a box in one point perspective

1. Draw a horizon and place a vanishing point

(VP) somewhere on this line.

2. Draw a square somewhere beneath the

horizon. This will be the front of your box

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3. Draw four lines, one from each corner of 

the square which also pass through the

vanishing point.

4. To complete the box, draw in the back

vertical and an horizontal

The final box in all its glory!

Two Point PerspectiveTwo Point Perspective is a much more useful

drawing system than the simpler One Point

Perspective. Objects drawn in two point

perspective have a more natural look.

In two point perspective the sides of the

object vanish to one of two vanishing points

on the horizon. Vertical lines in the object

have no perspective applied to them.

The illustration to the right demonstrates the

how to draw a box in two point perspective.

1.  Put two vanishing points at opposite ends

of the horizontal line.

2.  Draw in the front vertical of the box.

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Drawing the line below the horizontal will

create a view which we are looking down

on. To look at the object from below,

draw the front vertical above the

horizontal.

3.  Draw lines from the top of the vertical

which disappear back to both of the

vanishing points. Repeat the process for

the bottom of the line.

4.  To complete both of the sides by drawing

in the back verticals.

5.  To draw the top of the box, draw lines

from the back verticals to the opposite

vanishing points. 

By altering the proximity of the vanishing points to the object, you can make the object look big or small.

Vanishing Points close to the object Vanishing Points far away from product

Constructing circles in perspective

A circle when viewed at an angle does not look circular but

elliptical. For example look at the way the red circle gradually

changes to a thinner and thinner ellipse as the disc rotates.

When a circle is drawn inside a square, the circle touches the edge

of the square at the midpoint of each side. This enables you to

create a guide for your perspective circle since you know that the

circle must touch the midpoint of a square drawn in perspective.

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To find the midpoints of a perspective square, draw in the diagonals to find the centre of 

the box and then draw a vertical line through this centre point and a line going through the

centre to the vanishing point. The ellipse can be drawn in by hand.

Perspective ellipse templates similar to isometric templates can also be bought. These

come in a variety of sizes from 5 - 250 mm at various angles. The perspective of each

template varies from fat almost circular ellipses to long thin ellipses.

Using ellipse templates is very easy; every ellipse has a minor and major axis marked on it.So once you've drawn a perspective square, draw in the diagonals. These are the major

and minor axis. It then a simple case of finding the correct ellipse to use.

Drawing cylinders in perspective

Many students find drawing cylinders difficult. The secret to drawing a cylinder is to

construct the cylinder from a box as illustrated. First lightly sketch your box. Construct a

perspective circle at each end of the box. Then draw in the edges. Once you have the basic

shape you can ink in the shape and add shading.

Constructing a grid (1)

Once you can construct a simple box in perspective you can move on to more complex designs using the

simple box as a guide by subdividing it into smaller boxes creating a perspective grid.

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1. Draw a box in perspective  2. Draw diagonals from corner to corner. This

point is the centre of the box tacking into account

perspective 

3. Subdivide the box into four smaller boxes bydrawing in centre lines for the box. These centre

lines should go through the centre point found in

step 2. 

4. Repeat step 2 for each of the four new boxes. 

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5. Subdivide these boxes into smaller boxes.  6. You now have a gird with with to work with. 

Constructing a grid (2)

There is a second method of constructing a grid using a cube as the building block.

If you draw two squares side by side and split the

left hand square into four equal boxes. A line can

be drawn diagonally from a corner of the squarethough the midpoint of the opposite side which

will meet the far corner of the other square. You

can extend this technique to construct adjacent

perspective cubes.

1. Start by drawing a cube in perspective.

Find the centre of one of the sides of the

cube by drawing in diagonals

2. Draw a line extending through this centre, back to

the vanishing point.

3. Extend the top of the cube back towards 4. Draw a line from the corner of the cube through

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the vanishing point. the midpoint so that it bisects the line we have just

drawn.

5. This point coincides with the back of the

next cube. Draw in the back vertical and top

of the cube.

6. By using steps 1-5 one cube can be extended so

that it forms a grid.

Using the grid

Split your object into squares, corresponding to your perspective grid. Draw onto the perspective grid the detail

by finding the position on the flat view and using the grid as a guide. The example below shows how you can

create a cassette in perspective.

Three Point Perspective

Three point perspectives is a development of two point perspective. Like two point it has

two vanishing points somewhere on the horizon. But three point perspectives also have avanishing point somewhere above or below the horizon which the vertical vanish to.

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The nearer the vanishing point is to the object, the bigger

the object looks.

Look at these buildings. All the vanishing points are tooclose. This has caused an excessive amount of vertical

perspective. Learning how to apply vertical perspective is

the key to making your drawings realistic.

In general most designers create drawings with a vanishing point

far below the horizon so that the depth added to the verticals is

only slight. In many cases the vanishing point isn't even on the

paper. Learning how to apply vertical perspective will make your

drawings more and more realistic.

Drawing cavities in objects

Some students when they first start to draw using a 3D system, whether it's isometric,

perspective or oblique, do not stick to the system due to their lack of understanding of 

how to represent objects. One circumstance in which students produces incorrect

drawings is when they draw circles, this has been covered. Another circumstance where

students make mistakes, showing a lack of special awareness, is when they draw spaces in

objects (such as a cupboard space or a drawer).

Many students draw cupboards like this.

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This is supposed to

be in one point

perspective. Note

how the cupboard

space doesn't

vanish into the

distance the rest of 

the cupboard, butinstead vanishes to

its own vanishing

point.

This view could mean one of two things.

Either there is a

'pyramidal' shapesticking out of the

cupboard or the

'pyramidal' shape

has been removed

from the cupboard

to create the

space. But the

space is definitely

not the cubic space

intended.

When you draw a space in an object you are removing a volume so you should draw that

volume and then ink in the bit you see. See the examples below

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Oblique  Isometric 

1 Point Perspective 2 Point Perspective

Improving your sketching skills

As a designer the most important thing is to get your ideas on to paper as quickly as possible. Sketching is

therefore a very important skill to master. There are a few things which will help you sketch better.

Draw using your shoulder rather than your wrist.

To sketch quickly learn to sketch from your shoulder. Most people learn to sketch on small pieces of paper,usually no bigger than A4, sketching small images. Because the images are small, people tend to learn how to

sketch from the wrist. Drawing a long line tends to consist of lots of small movements from your wrist, as you

move your arm along. If you look carefully at these lines they consist of lots of small arches.

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Sketching from your shoulder means that you can draw lines in one

continuous movement. Instead of drawing by moving your wrist, keep

your wrist still and move your entire arm in one long movement from

your shoulder. It's not an easy skill to master but once you have, you

definitely will see the benefit.

A good way to learn is to practice drawing on large A2 sheets of paper

and have the paper vertical. This means that you can't rest your wrist

on the page encouraging you to use your shoulder when drawing.

There is a simple exercise that can help. Draw a series of opposing

vertical and horizontal dots at each end of a piece of paper. Practice

drawing a continuous line from one dot on one side of the paper to th

dot on the opposite side of the paper. Gaining confidence in your

drawing action is vital to improving your sketching skills.

Choosing the best type of paper

As mentioned above, sketching skills tend to improve if you use large

pieces of paper. Learning to sketch on A2 paper is a very good way of gaining confidence in your skill. But most

people find A2 an inconvenient size for project work. If you can, try to do sketches for your project on A3. Buy a

pad of layout paper. This type of paper is useful because it is slightly opaque. When drawing final ideas you can

quickly sketch your basic idea getting proportions correct and then use another sheet of layout paper placed

above to trace the original sketch without mistakes and guide lines.

Sketching in pen

When sketching, pencils are the obvious choice, but I recommend using a biro for the simple reason that youcan't rub out biro. This means that you will learn to put down only the marks that you really want to. Also you

won't be tempted to rub out ideas. Never rub out an idea it shows the examiner that you have thought about

your design and not just developed your only idea. Besides, occasionally you find that you can use some elemen

of discounted designs.

Drawing box guides

A simple way to get the proportions of your idea correct is to sketch boxes in perspective. See the 'Drawing in 3D

section for more information about the various 3D sketching skills you can learn to master.

Engineering Drawing

Planning your engineering drawing

Line Styles

Dimensioning

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Types of Dimensioning

Dimensioning Circles

Dimensioning Holes

Dimensioning Radii

Tolerancing

Layout of Engineering Drawing

Orthographic Projection

Sectioning

Types of sectioning

Hatching

Drawing thread parts

Assembly Drawings

Planning your engineering drawing

Before starting your engineering drawing you should plan how you are going to make best use of the space. It is

important to think about the number of views your drawing will have and how much space you will use of the

paper.

Try to make maximum use of the available space.

If a view has lots of detail, try and make that view as large as possible. If necessary, draw that view on a separate

sheet.

If you intend to add dimensions to the drawing, remember to leave enough space around the drawing for them to

be added later.

If you are working with inks on film, plan the order in which you are drawing the lines. For example you don't wantto have to place your ruler on wet ink

Lines and line styles

In the first tutorial we learnt how to create simple shapes using the place line tool. The lines we created were al

of the same thickness and type. But lines on an engineering drawing signify more than just the geometry of the

object and it is important that you use the appropriate line types.

Line Thickness

For most engineering drawings you will require two thicknesses, a thick and thin line. The general

recommendation is that thick lines are twice as thick as thin lines.

A thick continuous line is used for visible edges and outlines.

A thin line is used for hatching, leader lines, short centre lines, dimensions and

projections.

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Line Styles

Other line styles used to clarify important features on drawings are:

Thin chain lines are a common feature on engineering drawings used to indicate

centre lines. Centre lines are used to identify the centre of a circle, cylindrical features

or a line of symmetry. Centre lines will be covered in a little bit more detail later in thi

tutorial.

Dashed lines are used to show important hidden detail for example wall thickness andholes..

Dimensioning - An Overview

A dimensioned drawing should provide all the information necessary for a finished product or part to be

manufactured. An example dimension is shown below.

Dimensions are always drawn using continuous thin lines. Two projection lines indicate where the dimension

starts and finishes. Projection lines do not touch the object and are drawn perpendicular to the element you aredimensioning.

In general units can be omitted from dimensions if a statement of the units is included on your drawing. The

general convention is to dimension in mm's.

All dimensions less than 1 should have a leading zero. i.e. .35 should be written as 0.35

Lettering

All notes and dimensions should be clear and easy to read. In general all notes should be written in capital letter

to aid legibility. All lettering should be of the same size and preferably no smaller than 3mm. An exampletypeface is shown below.

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Types of dimensioning

Parallel Dimensioning

Parallel dimensioning consists of several dimensions

originating from one projection line.

Superimposed Running Dimensions

Superimposed running dimensioning simplifies

parallel dimensions in order to reduce the space used

on a drawing. The common origin for the dimension

lines is indicated by a small circle at the intersection

of the first dimension and the projection line. In

general all other dimension lines are broken.

The dimension note can appear above the dimension

line or in-line with the projection line

Chain Dimensioning

Chains of dimension should only be used if the

function of the object won't be affected by theaccumulation of the tolerances. (A tolerance is an

indication of the accuracy the product has to be made

to. Tolerance will be covered later in this chapter).

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Combined Dimensions

A combined dimension uses both chain and paralleldimensioning.

Dimensioning by Co-ordinates

Two sets of superimposed running dimensions

running at right angles can be used with any features

which need their centre points defined, such as holes.

Simplified dimensioning by co-ordinates

It is also possible to simplify co-ordinate dimensions

by using a table to identify features and positions.

Dimensioning Small Features

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When dimensioning small features, placing the dimension arrow between projection lines may create a drawing

which is difficult to read. In order to clarify dimensions on small features any of the above methods can be used.

Dimensioning circles

All dimensions of circles are proceeded by this symbol; . There are several conventions used for dimensioning

circles:

(a) shows two common methods of dimensioning a circle. One method dimensions the circle between two lines

projected from two diametrically opposite points. The second method dimensions the circle internally.

(b) is used when the circle is too small for the dimension to be easily read if it was placed inside the circle. A

leader line is used to display the dimension.

(c) the final method is to dimension the circle from outside the circle using an arrow which points directly

towards the centre of the circle.

The first method using projection lines is the least used method. But the choice is up to you as to which you use.

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Dimensioning Holes

When dimensioning holes the method of manufacture is not specified unless they necessary for the function of 

the product. The word hole doesn't have to be added unless it is considered necessary. The depth of the hole is

usually indicated if it isn’t indicated on another view. The depth of the hole refers to the depth of the cylindrical

portion of the hole and not the bit of the hole caused by the tip of the drip.

Dimensioning Radii

All radial dimensions are proceeded by the capital R. All

dimension arrows and lines should be drawn perpendicular to

the radius so that the line passes through the centre of the arc.

All dimensions should only have one arrowhead which should

point to the line being dimensioned. There are two methods

for dimensioning radii.

(a) shows a radius dimensioned with the centre of the radius

located on the drawing.

(b) shows how to dimension radii which do not need their

centres locating.

Spherical dimensions

The radius of a spherical surface (i.e. the top of a drawing pin) when dimensioned should have an SR before the

size to indicate the type of surface.

Tolerancing

It is not possible in practice to manufacture products to the exact figures displayed on an engineering drawing.

The accuracy depends largely on the manufacturing process used and the care taken to manufacture a product.

A tolerance value shows the manufacturing department the maximum permissible variation from the dimension

Each dimension on a drawing must include a tolerance value. This can appear either as:

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a general tolerance value applicable to several dimensions. i.e. a note specifying that the General Tolerance +/- 0.5

mm.

or a tolerance specific to that dimension

The method of expressing a tolerance on a dimension as recommended by the British standards is shown below

Note the larger size limit is placed above the lower limit.

All tolerances should be expressed to the appropriate number to the decimal points for the degree of accuracy

intended from manufacturing, even if the value is limit is a zero for example.

45.25  should not be expressed as 45.25 

44.80  44.8 

The layout of an engineering drawing

It is important that you follow some simple rules when producing an engineering drawing which although may

not be useful now, will be useful when working in industry.

All engineering drawings should feature an information box. An example is shown below.

Common information recorded on an engineering drawing

TITLE 

The title of the drawing.

NAME 

The name of the person who produced the drawing. This is important for quality control so that problems with the

drawing can be traced back to their origin.

CHECKED 

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In many engineering firms, drawings are checked by a second person before they are sent to manufacture, so that

any potential problems can be identified early.

VERSION 

Many drawings will get amended over the period of the parts life. Giving each drawing a version number helps

people identify if they are using the most recent version of the drawing.

DATE 

The date the drawing was created or amended on.

SCALE 

The scale of the drawing. Large parts won't fit on paper so the scale provides a quick guide to the final size of the

product.

PROJECTION SYSTEM 

The projection system used to create the drawing should be identified to help people read the drawing. (Projectio

systems will be covered later).

COMPANY NAME 

Many CAD drawings may be distributed outside the company so the company name is usually added to identify th

source.

Orthographic projection

The aim of an engineering drawing is to convey all the necessary information of how to make the part to the

manufacturing department. For most parts, the information cannot be conveyed in a single view. Rather than

using several sheets of paper with different views of the part, several views can be combined on a single drawing

using one of the two available projection systems, first angle, and third angle projection.

The diagram below demonstrates how the projection systems work

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Sectioning - Introduction

Sections and sectional views are used to show hidden detail more clearly. They are created by using a cutting

plane to cut the object.

A section is a view of no thickness and shows the outline of the object at the cutting plane. Visible outlines

beyond the cutting plane are not drawn.

A sectional view, displays the outline of the cutting plane and all visible outlines which can be seen beyond thecutting plane. The diagram below shows a sectional view, and how a cutting plane works.

Types of sectioning

Sectional View in a single plane

The example below shows a simple single plane sectional view where object is cut in half by the cutting plane.

The cutting plane is indicated on a drawing using the line style used for centre lines, but with a thick line

indicating the end of lines and any change in the direction of the cutting plane. The direction of the view is

indicated by arrows with a reference letter. The example below shows a sectional view of the cutting plane A - A

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Sectional View in two planes

It is possible for the cutting plane to change directions, to minimize on the number of sectional views required to

capture the necessary detail. The example below shows a pipe being cut by two parallel planes. The sketch

shows where the object is cut.

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Half Sectional views

Half sections are commonly used to show both the internal and outside view of symmetrical objects.

Part Sectional views

It is common practice to section a part of an object when only small areas need to be sectioned to indicate the

important details. The example above shows a part sectional view to indicate a through-hole in a plate. Notice

that the line indicating the end of the section is a thin continuous line.

Which Sectional View?

Before proceeding, consider the diagrams below and select the correct sectional view.

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Hatching

On sections and sectional views solid area should be hatched to indicate this fact. Hatching is drawn with a thin

continuous line, equally spaced (preferably about 4mm apart, though never less than 1mm) and preferably at an

angle of 45 degrees.

Hatching a single object

When you are hatching an object, but the objects have areas that are separated, all areas of the object should b

hatched in the same direction and with the same spacing.

Hatching Adjacent objects

When hatching assembled parts, the direction of the hatching should ideally be reversed on adjacent parts. If 

more than two parts are adjacent, then the hatching should be staggered to emphasize the fact that these parts

are separate.

Reverse hatching Staggered Hatching

Hatching thin materials

Sometimes, it is difficult to hatch very thin sections. To emphasize solid wall the walls can be filled in. This should

only be used when the wall thickness size is less than 1mm

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.

Hatching large areas

When hatching large areas in order to aid readability, the hatching can be limited to the area near the edges of 

the part.

Drawing threaded parts

Drawing Conventions

A threaded part

Threads are drawn with thin lines as shown in this

illustration. When drawn from end-on, a threaded section is

indicated by a broken circle drawn using a thin line.

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Frequently a threaded section will need to be

shown inside a part. The two illustrations to the

left demonstrate two methods of drawing athreaded section. Note the conventions. The

hidden detail is drawn as a thin dashed line. The

sectional view uses both thick and thin line with

the hatching carrying on to the very edges of the

object.

Assembly Drawings

The previous chapters covered the general aspects of engineering drawing and how to produce a detailed

drawing of a single part with all the necessary information to make the part. The assembly of these parts is

shown in an assembly drawing also known as a general arrangement.

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Features of an assembly drawing

Dimensions 

Detailed dimensions required for manufacture are excluded

from assembly drawings. But overall dimensions of the

assembled object are usually indicated.

If the spatial relationship between parts if important for the

product to function correctly then these should also be

indicated on the drawing. For example idicating the maximum

and minimum clearance between two parts.

Internal Parts 

If there are internal assemblies, sectional views should be used.

Parts list 

Each part is given a unique number, indicated on the drawing by

a circle with the number in it and a leader line pointing to the

part. The leader line terminates in an arrow if the line touches

the edge of the component or in a circle if the line terminates

inside the part.

A table of parts should be added to the drawing to identify each

part, an example of a parts list is shown below:

Item No.  Description  Qty  Material  Remarks 

The first three items; Item No., Description, and Quantity should

be completed for every distinct part on your drawing. (i.e. the

number of duplicate parts are recorded in the quantity). The

material is used for components that are being made within the

company. The Remarks column is useful for specifying a

manufacturer’s part number when using bough-in parts.

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Energy sources

Energy cannot be created or destroyed but only converted from one form to another. That is the meaning of 

Einstein's well-known theory E=mc2.

In practice though, it seems to the user that energy is lost, but this is untrue. The energy used to power, say a

motor, is converted into heat and noise. This is extremely difficult to convert back to a more practical form, soenergy seems to be lost and more energy has to be ploughed into the system to keep it going.

There are several sources of energy some of the more common are listed below

Non renewable energy sources

Fossil Fuels

Renewable Energy Sources

Solar Energy

Hydroelectric Power

Wind Energy

Geothermal Energy

Ocean Thermal Energy

Nuclear Energy

Ergonomics and Anthropometrics

Anthropometrics 

Anthropometrics is the study and recording of the physical properties of the human body.

Ergonomics 

Ergonomics investigates how we use our environment and the design of environments which enable users to us

the environment easily and comfortably. An example of where ergonomics is used is the design of the cockpit of

an aircraft.

Anthropometric Data

The anthropometrics of an average male and female

Materials

Materials

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Material Types

Metals

Woods

Plastic

Adhesives

Material Structures

Atoms

Atomic Bonds

General Information

Costs of various materials relative to the cost of carbon steel.

Manufacturing

The way in which a product is made has a big effect on decisions taken by the designer during the design phase,

after-all it is important that the product can be made. It is vitally important therefore that the correctmanufacturing processes are chosen at the design stage so that your design doesn't have to be changed later.

Obviously in industry, the aim is to produce a design which requires as little change as possible when being

made, because change costs time, and time cost money!. In some engineering sectors you may design somethin

in the morning, it will be made in the afternoon and reach the customer the next day!

This section looks at many different aspects of manufacturing a product. Although it contains many techniques

which can't be reproduced in schools and colleges, good students will demonstrate knowledge of appropriate

mass production techniques throughout their projects even though you might not be able to achieve the desired

effect in the workshop.

Manufacturing Processes and techniques 

Covers techniques such as casting, fabrication, plastic moldings and welding.

Virtual Workshop 

Our virtual workshop showing some of the machines you might find in your workshop.

Workshop Techniques (external link) 

How to safely use common machines in your workshop.

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Costing

All manufacturing companies sell their products to make profit . The profit on each

product sold can be defined as the difference between the selling price of the

product and the total cost of making the product. Cost therefore plays a very

important role in the product design process. To be successful, a product must not

only satisfy a set of functions defined in the product design specification, but it

must also be possible to build the product within the cost criteria set out at the

start of the project. Before the development of any product begins, it is essential

to perform some form of economic analysis on the product to determine if it is

worth making. This may involve some form of market analysis to determine what

the customer is willing to pay for a product.

The costs involved in any product can be spilt into development costs and the

product cost. Interestingly, some companies do not actually know what their costs

are which leaves them open to the possibility that their actual costs may be more

than the selling price of their product! An example of this was the Mini when it

was first produced in the early 60’s. Market research suggested that the car

should be sold for less than £500 so the company priced the car at £499. Later

when they analysed the cost of producing the car they found that the car costaround £530 to build, resulting in large losses for the manufacturer.

Development Costs 

Product Costs 

Component Costs

Material Costs

Manufacturing Costs

Storage Costs

Marketing

Marketing can be seen as fulfilling two important roles in an organisation. Determining the market requirement

for a new (or revised product) and actually selling that product. By determining the market requirements

marketing can play a vitally important role in the product design process.

The role of marketing when you are developing your product

Selling your product

The role of marketing in product development

The requirements of a new or revised product are typically dictated by one of two sources.

1.  A customer will approach a manufacturer (or a number of manufacturers) with the requirements of a product. It is

likely that the customer has a good idea of the requirements of the product so the role of marketing is likely to be

reduced to the role of advertising your companies services.

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2.  With no one particular customer to provide the requirements, an analysis of the existing marketplace and talking

with potential customers can determine what the requirements of a product should be and try and find some nich

or opening for a new product to occupy. This implies that the organization must do extensive market research in

order to determine what requirements the product must satisfy. There is no point developing a product, no matte

how well engineered, if there is no market for it. The marketing department will therefore have an important role,

both identifying if the product should be developed but also developing a plan to sell the product to the market.

Whichever ways the requirements of the product are identified, the needs of the customer have a large influenc

on the decisions taken by designers. The marketing department will therefore have a major influence on the

drawing up of the product design specification (PDS). The PDS is a vitally important document in the design

process as it contains all the information necessary for a design team to successfully specify the requirements of

the final product.

Analyzing the market

One way to decide on the features your product needs to have is to analyze what your competitors’ products

have. There are a number of different techniques available to analyze the market to identify the requirement of 

your product. These include:

Parametric analysisNeeds analysis

Matrix analysis

Finding out about what the user wants

Focus Groups

Market Surveys

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Bibliography

References

1.  What is Technical Drawing?

2.  David L. Goetsch et al. (2005). Technical Drawing. Cengage Learning, 2005.3.  Gary R. Bertoline et al. (2002) Technical Graphics Communication. McGraw-Hill Professional, 2002.

4.  James Folkestad er al. (2001). Engineering Drawing & Design. Cengage Learning, 2001.

5.  Ken Baynes, Francis Pugh (1981) The Art of the Engineer . James Clarke & Co., 1981.

6.  J. Diepstraten, D. Weiskopf & T. Ertl (2003). "Interactive Cutaway Illustrations". 

7.  Michael E. Brumbach, Jeffrey A. Clade (2003). Industrial Maintenance. Cengage Learning,

8.  Ivan Viola and Meister E. Gröller (2005). "Smart Visibility in Visualization". In: Computational Aesthetics in

Graphics, Visualization and Imaging. L. Neumann et al. (Ed.)

9.  www.industriegrafik.com website, Last modified: Juni 15, 2002. Accessed 15 feb 2009.

10. Richard Boland and Fred Collopy (2004). Managing as designing. Stanford University Press, 2004.

11.  Auto CAD tutorial

12. About.com Information provided by P E Waters, Secretary and Registrar Document last updated 7th May, 2002