chapter 1 drawing in auto cad 2010

Copyright ©2009 by K. PlantenbergRestricted use only

Chapter 1Drawing in AutoCAD

TopicsExercises


Drawing AutoCAD: TopicsSummary1.1) Introduction1.2) AutoCAD’s User Interface1.3) The Drawing Area1.4) Accessing AutoCAD Commands1.8) Coordinates1.11) Printing1.13) Draw Commands


Drawing AutoCAD: Topics1.14) Text1.15) Modify Commands1.16) Object Snap Commands1.18) Selecting Objects1.21) Polar Tracking1.22) Object Snap Tracking1.24) Dynamic Input1.26) Grip Boxes1.28) Parametric Drawing


Drawing AutoCAD: ProblemsProblem 1-1: Relative CoordinatesProblem 1-2: Scale


Drawing in AutoCAD

Summary


Summary What will we learn in Chapter 1?

→ How to navigate through and create drawings in AutoCAD’s 2-D drawing environment.

Key points→ AutoCAD creates objects within a

coordinate system.


Drawing in AutoCAD

1.1) Introduction


Introduction AutoCAD gives you the tools to create

accurate and professional looking detailed and assembly drawings.


Drawing in AutoCAD

1.2) AutoCAD’s Workspaces and User Interface


Workspaces AutoCAD Classic: Allows access to all

commands.

2D Drafting & Annotation: Contains commands related to 2D drawings.

3D Modeling: Allows you easy access to commands related to 3D models


Workspaces Open up AutoCAD 2010 and enter the

AutoCAD Classic workspace.


Workspaces Enter the 2D Drafting & Annotation

workspace.


Drawing in AutoCAD

1.3) The Drawing Area


The Drawing Area The drawing area is the place where you

create and view your drawing. → The background color may be changed.


The Drawing Area Useful Commands

→ Limits: Sets the drawing size.→ Units: Controls the measurement precision

(decimal places) and units (i.e. mm, inch) .→ Pan: Moves the view center.→ Zoom: Reveals more or less of the drawing

area.Live demonstration


Drawing in AutoCAD

1.4) Accessing AutoCAD Commands


Accessing AutoCAD Commands 2D Drafting & Annotation

→ Ribbon panels AutoCAD Classic

→ Pull-down menus→ Toolbars

Common to both→ Command window→ Shortcut menus→ Drawing Status bar→ Tool palettes

Live demonstration


Starting a New Drawing QNew... STARTUP = 1 (Template

window)


Starting a New Drawing QNew... STARTUP = 0 (Create New

Drawing window)


Drawing in AutoCAD

1.8) Coordinates


Cartesian & Polar Coordinates In AutoCAD, lines, circles and etc... are

defined by coordinate points.

The two main coordinate systems used are the → Cartesian coordinate system (x,y) → polar coordinate system (r,q).


Cartesian Coordinate System The Cartesian coordinate has three

mutually perpendicular axes (x-axis, y-axis z-axis).


Cartesian Coordinate System The origin is located at (0,0,0).

Origin


Creating a Line Command: l or line LINE Specify first point: 2,1


Creating a Line Specify next point or [Undo]: 6,3 Specify next point or [Undo]: Enter


Polar Coordinate System The 2-D polar coordinate system consists

of two mutually perpendicular axes (x-axis, y-axis).


Polar Coordinate System The origin is located at (0,0).

Origin


Polar Coordinate System The location of any point in space can be

identified by the radial coordinate r and the angular coordinate q.


Polar Coordinate System The angular coordinate q is measured

counterclockwise starting at the positive x-axis.


Creating a Line Command: l or line LINE Specify first point: 2.5<60


Creating a Line Specify next point or [Undo]: 7<10 Specify next point or [Undo]: Enter


Relative Coordinates If the start point of a line is unknown, you

can enter relative coordinate points to create the end point.→ The symbol @ is placed before the

coordinate point if it is to be relative to the last point entered.


Creating a Line Command: l or line LINE Specify first point: unknown


Creating a Line Specify next point or [Undo]: @4,2 Specify next point or [Undo]: Enter


Creating a Line Command: l or line LINE Specify first point: 2,1


Creating a Line Specify next point or [Undo]: @5<25 Specify next point or [Undo]: Enter


WCS & UCS Coordinate Systems AutoCAD has two different coordinate

frames; → world coordinate system (WCS), which is

fixed and cannot be moved → user coordinate system (UCS), which may

be translated and rotated


UCS Panel Command: UCS Specify origin of UCS or [Face/NAmed/

Object/Previous/View/World/X/Y/Z/ ZAxis] <World>:

Origin World

Rotate


Coordinate Position The coordinate position of your cursor is

displayed at the bottom left of the drawing area.

It dynamically states the x, y, z or r, q position of your cursor. → The command COORDS controls which is

stated.

Live demonstration


Drawing in AutoCAD

1.11) Printing


Printing To print, you need to specify a print

region. → Display: Prints everything that you can

see, at the moment, in the drawing area.→ Extents: Prints the minimum area which

will include everything that is drawn.→ Limits: Prints the area that you have

defined as your drawing size.→ Window: Prints the area that you select

using a window.

Box indicating the limits.

This is what you see.



This is what prints.DISPLAY



This is what prints.EXTENT



This is what prints.LIMITS


Page Setup Printing preferences for a particular

drawing may be set in the Page Setup - Model window. → These settings are drawing specific which

means that they are stored in the drawing or template file and not in the program.


Plot The Plot – Model window allows you to

send your drawing to a printer or plotter. → The default settings used to print your

drawing are specified in the Page Setup – Model window.

→ The Plot – Model window allows you to change some of these default settings. • (Not stored in the drawing.)


Printing to Scale Print scale expresses the ratio between

the printed size of an object to its actual size. → Full-scale (1:1): 1 inch measures 1 inch

with a ruler on the printed drawing. → Half-scale (1:2): 1 inch measures ½ inch

with a ruler on the printed drawing.→ Quarter-scale (1:4): 1 inch measures ¼

inch with a ruler on the printed drawing.


Printing to Scale Even though a drawing may not be able to

be printed full scale, it should always be drawn full scale in the CAD environment.


Printing to Scale Although it is nice to print to scale, the

ASME standard states that no dimension should be measured directly from the printed drawing.

For drawings that have no scale, the word “NONE” is used.


Drawing in AutoCAD

1.13) Draw Commands


Draw panel

Line

Polyline Polygon

Rectangle

Arc

EllipseCircle

Hatch

Construction Line


Draw Commands Each draw command has several options.

→ Look at the Command prompt.

Command: circle Specify center point for circle or [3P/2P/Ttr

(tan tan radius)]:


Draw Commands Each draw command has several options.

→ Look at the Command prompt.

Command: rectangle Specify first corner point or [Chamfer/

Elevation/Fillet/Thickness/Width]: Specify other corner point or [Area/

Dimensions/Rotation]:


Drawing in AutoCAD

1.14) Text


Style Command: Style

→ Sets the default text font and size.


Single Line Text Command: Text

→ Creates a single line of text.

It has several justification options.→ Enter an option [Align/Fit/Center/Middle

/Right/TL/TC/TR/ ML/MC/MR/BL/BC/BR]:


Multiline Text


Multiline Text Command: MText

→ Activates an in place text editor.

Live demonstration


Drawing in AutoCAD

1.15) Modify Commands


Modify Toolbar / Control panel

Erase

CopyMove Rotate

Fillet/ChamferExplode


Modify Toolbar

Mirror


Modify Toolbar

Offset


Modify Toolbar

Array


Modify Toolbar

Rotate


Modify Toolbar

Scale


Modify Toolbar

Stretch


Modify Toolbar

Trim


Modify Toolbar

Extend (under Trim)


Modify Toolbar

Break


Drawing in AutoCAD

1.16) Object Snap Commands


Object Snap Toolbar Osnaps allow you to snap to specific

geometric locations on an existing object. → They allow you to draw quickly and

accurately. → Snap points are indicated by Osnap

markers.

Live demonstration


Object Snap Toolbar

Endpoint Midpoint Intersection

Center point

Quadrant

Tangent

Perpendicular

Parallel Nearest

Settings


Object Snap Toolbar

Extension


Drawing in AutoCAD

1.18) Selecting Objects


Selecting Objects Common ways of selecting objects

→ Selecting objects using the pickbox → Window selection → Crossing window selection (CW)


Selecting Objects Useful Commands

→ Pickadd: • PICKADD = 0 The object will replace the

selected object • PICKADD = 1 The object will be added to the

selection group → Remove (R): Removes an object from the

selection group.→ Add (A): Adds an object to the selection

group.Live demonstration


Drawing in AutoCAD

1.21) Polar Tracking


Polar Tracking Polar tracking restricts cursor movement

to specified angles. (POLARANG)

Live demonstration


Drawing in AutoCAD

1.22) Object Snap Tracking


Object Snap Tracking Object snap tracking enables you to

track along paths that are based on OSNAP point.

Live demonstration


Drawing in AutoCAD

1.24) Dynamic Input


Dynamic Input Dynamic input provides a command

interface near the cursor to help you keep your focus in the drawing area.

Live demonstration


Drawing in AutoCAD

1.26) Grip Boxes


Grip Boxes Object grips or grip boxes allow you to

quickly modify the object.

Live demonstration


Drawing in AutoCAD

1.28) Parametric Drawing


Parametric Panel The commands located in the Parametric

panel allow you to apply geometric and dimensional constraints to 2D drawings


Geometric Constraints

CoincidentColinear

ConcentricFix

Parallel

Tangent

VerticalEqual


Geometric Constraints

PerpendicularHorizontal

SmoothSymmetric


Dimensional Constraints The size of the element will

automatically change if the value of the dimension is changed.


Dimensional Constraints You have the ability to relate one

dimension to another through an equation.


Dimensional Constraints

Radius Diameter

Angle


Problem 1-1

Relative Coordinates


Problem 1-1: Relative coordinates Fill in the relative Cartesian coordinates

needed to draw the following object.

How do we draw this line?

@0,30




@0,30@40,0




@0,30@40,0

@0,-20




@0,30@40,0

@0,-20

@20,0




@0,30@40,0

@0,-20

@20,0

@0,-10




@0,30@40,0

@0,-20

@20,0

@0,-10

@-60,0


Problem 1-1: Relative coordinates Fill in the relative Polar coordinates


How do we draw this line?

@30<90




@40<0@30<90




@40<0@20<-90

@30<90




@40<0 @20<0@30<90

@20<-90




@40<0 @20<0

@10<-90

@30<90

@20<-90




@40<0 @20<0

@60<180

@30<90

@20<-90

@10<-90


Problem 1-2

Scale


Problem 1-2: Scale Using the ruler provided, determine the

scale that should be indicated on the drawing for the following objects.

1:1




1:2




4:5

chapter 1 drawing in auto cad 2010

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