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ROTATE
The rotate command changes the orientation of existing entities by rotating them
about a specified base point. The rotation angle may be given as a numeric value or
by dragging the entity.
There are two methods of doing this.
1. Type Rotate or just Ro at the command prompt.
2. Click Rotate from the Modify icon.

ROTATE

Select object :
Select base point:

Rotation angle:

Example 1 :
Command : Rotate
Select objects : pick object
Base point : select base point
<Rotation angle>/ Reference : 90 ( rotate 1) or
<Rotation angle>/ Reference : -90 ( rotate 2)

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BREAK

The Break command is a convenient way to create a gap in an object, resulting in two
objects with a space between them. Break is often used to create space for block or
text insertion.
There are two methods of doing this.
1. Type Break or just Br at the command prompt.
2. Click Break from the Modify icon.

BREAK First point or type F
First point: pick point
Select object : Second point: pick 2nd point
Second break point or [First point]

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When breaking an object, you can either
a) select the object at the first break point and then specify a second break point, or
b) select the entire object and then specify two break points.

Example 1 :
Command: Break
Select the object to break: select P1
Specify the second object: @10<0

Example 2 :
Command: Break
Select the object to break: pick line
Specify second break point or [First point]: f
Specify first break point: select P1
Specify second break point: @10<0
Example 3 :
Command: Break
Select the object to break: pick P1 (QUAdrant)

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Specify second break point or [First point]: Pick P2 (QUAdrant)

Example 4 :
Command: Break
Select the object to break: pick P1 (QUAdrant)
Specify second break point or [First point]: Pick P2 (QUAdrant)
TRIM
The Trim command trims existing entities so that they end precisely at the cutting
edge(s). The cutting edges can be Lines, Arcs, Circles, open 2D polylines
There are two methods of doing this. Click Trim from the Modify icon.
1. Type Trim or just tr at the command prompt.

TRIM

Select cutting edges: pick 2 or more cutting edges
Select object to trim: pick 1 or more object to trim

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Example 1 :
Command : Trim
Select cutting edge : pick line ( cutting edges)
<Select object to trim>/ Project / Edge / Undo : pick line or cicle ( trim object)

SCALE
The Scale command enlarges or reduces selected objects equally in X and Y
directions. Entities can be enlarged if a scale factor greater than 1 is selected and can
be reduced in size if a scale factor between zero and 1 is selected.
There are two methods of doing this.
1. Type Scale or just sc at the command prompt.
2. Click Scale from the Modify toolbar.

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SCALE

Select object:
Select base point:
Specify scale factor or [Copy/Reference]:

Scale factor: Copy: Reference:
Scale factor:
Specify reference
length:

Specify new length:

Example 1 :
Command: scale
Select objects: pick original object
Specify base point: pick base point
Specify scale factor or [Copy/Reference] <1>: 2 or
Specify scale factor or [Copy/Reference] <1>: 0.5

Example 2 :
Command: scale
Select objects: pick original object
Specify base point: pick base point
Specify scale factor or [Copy/Reference] <1>: r
Specify reference length <1>: 2
Specify new length or [Points] <3>: 10

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MIRROR

The Mirror command creates mirror images of the existing object about a mirror line.
Then the original object may either be retained or deleted.
There are two methods of doing this.
1. Type Mirror or just Mi at the command prompt.
2. Click Mirror from the Modify toolbar.

MIRROR

Select object:
1st Point of Mirror Line:
2nd Point of Mirror Line:
Example 1 :
Command: mirror
Select objects: Specify opposite corner: 5 found
Select objects: select the original object
Specify first point of mirror line: pick mirror point
Specify second point of mirror line: 180
Erase source objects? [Yes/No] <N>:

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ARRAY
The Array command is used to make multiple copies of one or more objects in a
rectangular (rows and colums) or polar (circular) pattern.
There are two methods of doing this.
1. Type Array or just Ar from the command prompt.
2. Click Array from the Modify toolbar.

Rectangular Array

Example 1 :
Command: ARRAY
Select objects: pick original object
Enter array type [Rectangular/PAth/POlar] <Rectangular>: R
number of items or [Base point/Angle/Count] <Count>: C
Enter number of rows or [Expression] <4>: 3
Enter number of columns or [Expression] <4>: 2
Specify opposite corner to space items or [Spacing] <Spacing>: S
Specify the distance between rows or [Expression] : 20
Specify the distance between columns or [Expression] : 15
Accept or [ASsociative/Base point/Rows/Columns/Levels/eXit]<eXit>: X

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Polar Array

Example 3 :
Command: Array
Select object s : pick original object
Enter array type [Rectangular/PAth/POlar] <Rectangular>: PO
Specify center point of array or [Base point/Axis of rotation]: pick center point
Enter number of items or [Angle between/Expression] : 8
Specify the angle to fill (+=ccw, -=cw) or [EXpression] : 180
Accept or [ASsociative/Base point/Items/Angle between/Fill
angle/ROWs/Levels/ROTate items/eXit]<eXit>: X

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EXTEND
The Extend command lengthens existing entities so that they end precisely at the
boundary edge(s). The boundary edges can be lines, arcs, circles or 2D polylines. The
entities that can be extended are lines, arcs and open 2D polylines.
There are two methods of doing this.
1. Type Extend or just Ex at the command prompt.
2. Click Extend from the Modify toolbar.

EXTEND

Select boundary edges:
Select object to extend:

Example 1:
Command: Extend
Select boundary edges: pick boundary edge
Select objects: pick line to extend

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FILLET
The Fillet command connects two lines, arcs or circles with a smooth arc of a specified
radius. The value for the radius may be entered numerically or shown as the distance
between two points. The value of “0” for the radius results in a square corner.
There are two methods of doing this.
1. Type Fillet or just F at the command prompt.

2. Click Fillet from the Modify toolbar.

Trim FILLET Radius
Trim or No trim Fillet radius
Select first object:

Select second object:

Example 1 :
Command: Fillet
Current settings: Mode = NOTRIM, Radius = 0
Select first object or [Undo/Polyline/Radius/Trim/Multiple]: R
Specify fillet radius <0> : 5
Select first object or [Undo/Polyline/Radius/Trim/Multiple] <0>: pick 1st object
Select second object or shift-select to apply corner: pick 2nd object

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Example 2 :
Command: Fillet
Current settings: Mode = NOTRIM, Radius = 0
Select first object or [Undo/Polyline/Radius/Trim/Multiple]: R
Specify fillet radius <0> : 8
Select first object or [Undo/Polyline/Radius/Trim/Multiple] <0>: pick 1st object
Select second object or shift-select to apply corner: pick 2nd object
CHAMFER
Using Chamfer is a fast way of creating a line between two nonparallel lines. It is
usually used to represent a beveled edge on a corner. Chamfer can also be used to
bevel all corners of the polyline.
There are two methods of doing this.
1. Type Chamfer or just cha at the command prompt.
2. Click Chamfer from the Modify toolbar.

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CHAMFER

Trim Angle Select 1st line Distance
Trim or No trim Angle 1st line
1st chamfer distance

1st chamfer distance

Select 2nd line:

Example 1 :
Command: Chamfer
Select first line or [Undo/Polyline/Distance/Angle/Trim/mEthod/Multiple]: d
Specify first chamfer distance <0.0000>: 3
Specify second chamfer distance <1.0000>:2
Select 1stline or [Undo/Polyline/Distance/Angle/Trim/mEthod/Multiple]: pick 1st ine
Select 2nd line or shift-select to apply corner: pick 2nd line

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Example 2 :
Command: Chamfer
(NOTRIM mode) Current chamfer Dist1 = 3.0000, Dist2 = 2.0000
Select first line or [Undo/Polyline/Distance/Angle/Trim/mEthod/Multiple]: t
Enter Trim mode option [Trim/No trim] <No trim>: t
Select first line or [Undo/Polyline/Distance/Angle/Trim/mEthod/Multiple]: a
Specify chamfer length on the first line <0.0000>: 4
Specify chamfer angle from the first line <0>: 45
Select first line or [Undo/Polyline/Distance/Angle/Trim/mEthod/Multiple]: pick 1st
line
Select second line or shift-select to apply corner: pick 2nd line

OFFSET
The Offset command draws an entity parallel to another entity at either specified
distance or through a specified point. Line, arc, circle and 2D pline are the entities that
can be offset.
There are two methods of doing this.
1. Type Offset at the command prompt.
2. Click Offset from the Modify toolbar.

OFFSET

Example 1 :
Command: Offset
Current settings: Erase source=No Layer=Current OFFSETGAPTYPE=0
Specify offset distance or [Through/Erase/Layer] <0>: 5
Select object to offset or [Exit/Undo] <Exit>:
pick original object
Specify through point : select a point

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CHANGE
This command is used to change the points and properties of objects that have been
drawn. At command line type Change

Example 1:
Command: change
Select objects: pick original line
Specify change point or [Properties]: p
Enter property
[Color/Elev/LAyer/LType/ltScale/LWeight/Thickness/Material/Annotative]: LT
Enter new linetype name <Continuous>: dashed
Enter property to change [Color/Elev/LAyer/LType/ltS :

PEDIT
It is used for editing and joining Polylines. At command line type Pedit.

Example 1:
Command : Pedit
Select polyline or [Multiple] : pick original pline
Enter [Close/Join/Width/Edit Vertex/Fit/Spline/Decurve/Ltype gen/Undo] : w
Specify new width for all segments: 2 ( original pline width=1)

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Example 2:
Command: pedit
Select polyline or [Multiple]: pick polyline
Enter [Close/Join/Width/Edit vertex/Fit/Spline/Decurve/Ltype gen/Undo]: close
Enter [Close/Join/Width/Edit vertex/Fit/Spline/Decurve/Ltype gen/Undo]: Spline

polyline
Pedit change to Spline

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OBJECT SNAPS
Object Snaps allow objects to be added to a drawing at precise positions in relation
to other objects already on screen. With Object Snaps, objects can be added to the
endpoints and midpoints, to intersections of objects, to centers and quadrants of
circles and so on. Object Snaps also override snap points even when snap is set on.

To set Object Snaps – at the command line:
Command: OS enter, and the Drafting Settings dialog appears. Click the Object
Snap tab in the upper part of the dialog and click the check boxes to the right of the
Object Snap names to set them on (or off in on).

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When Object Snaps are set ON (F3), as outlines are constructed using Object
Snaps so Object Snap icons and their tooltips appear.

.

With Object Snaps off, the following abbreviations can be used by the keyboard and

type 1st three words of the object snaps command.

Examples:

CENter snaps from or to the center of an arc or circle.

ENDpoint snaps from or to the closest end of any object

EXTention snaps from or to a point along the extension of a line or

arc

INSertion snaps from or to the insertion point of a block

INTersection snaps from or to the intersection of two items

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NEARest
digitized point snaps from or to the midpoint of a selected item
NODe snaps from or to a point on an object nearest to the

NONe snaps from or to a point created by POINT, DIVIDE, or
PARallel MEASURE
PERpendicular turns the Object Snap mode off
QUAdrant draws a line parallel to an existing line
snaps to a 90-degree angle to an existing line
TANgent snaps from or to the 0, 90, 180, or 270-degree point on
an arc, circle, or ellipse
snaps from or to the tangent of an arc or circle

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07 DISPLAY CONTROL

ZOOM
You can change the magnification of a view by zooming in and out. Like zooming in
and out with a camera, Zoom does not change the absolute size of objects in the
drawing; it changes only the magnification of the view. When you work with minute
parts in your drawing, you may need to zoom out frequently to see an overview of your
work. Use Zoom Previous to return quickly to the prior view. There are two methods
of doing this.
1. Type Zoom or just Z at the command prompt.
2. Click Zoom from the Zoom toolbar.

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ALL
Zooms to display the entire drawing, AutoCAD zooms to the drawing limits or current
extents, which ever is greater. The display shows all objects even if the drawing
extends outside the drawing limits.
Example :
Command: Zoom
Specify corner of window, enter a scale factor (nX or nXP), or
[All/Center/Dynamic/Extents/Previous/Scale/Window/Object] <real time>: all

CENTER
Zooms to display a window by entering a center point. Then enter a magnification
value or height. A smaller value for the height increases the magnification. A larger
value decreases the magnification.
Example :
Command: Zoom
Specify corner of window, enter a scale factor (nX or nXP), or
[All/Center/Dynamic/Extents/Previous/Scale/Window/Object] <real time>: c
Specify center point: pick center point
Enter magnification or height <300>: 10

DYNAMIC
Zooms to display the generated portion of the drawing with a view box. The view box
represents your viewport, which you can shrink or enlarge and move around the
drawing. Positioning and sizing the view box pans or zooms to fill the viewport with the
image inside the view box. The panning view box is displayed first. Drag it to the
location you want and click. The zooming view box is then displayed. Resize it and
press ENTER to zoom or click to return to the panning view box.

Command: Zoom

Specify corner of window, enter a scale factor (nX or nXP), or
[All/Center/Dynamic/Extents/Previous/Scale/Window/Object] <real time>: d
Press ENTER to view Dynamic1, move to dynamic 2 (move right to change window
size) view after press ENTER.

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EXTENTS
Zooms to display the drawing extents and this will result in the largest possible display
of all the objects.
Example :
Command: Zoom
Specify corner of window, enter a scale factor (nX or nXP), or
[All/Center/Dynamic/Extents/Previous/Scale/Window/Object] <real time>: e
PREVIOUS
Zooms to display the previous view. You can restore up to 10 previous views.

SCALE (X/XP)
Zooms the display at a specified scale factor.
Enter a scale factor (nX or nXP): Specify a value
Example :
Command: Zoom
Specify corner of window, enter a scale factor (nX or nXP), or
[All/Center/Dynamic/Extents/Previous/Scale/Window/Object] <real time>: s
Enter a scale factor (nX or nXP): 2

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The value you enter is relative to the limits of the drawing. For example, entering 2
doubles the apparent display size of any objects from what it would be if you were to
zoom to the limits of the drawing.
WINDOW
Zooms to display an area specified by two opposite corners of a rectangular window.
Specify first corner: pick point first corner
Specify opposite corner: pick point other corner

PAN
It provides for the viewing of a different portion of a drawing on the display screen
without changing the magnification. If you enter Pan at the command prompt, Pan
presents alternative prompts on the command line. This version of Pan works in two
ways. You can specify a single point by indicating the relative displacement of the
drawing with respect to the current location. You can also specify two points, in which
case AutoCAD computes the displacement from the first point to the second point.
There are two methods of doing this.
1. Type Pan at the command prompt.
2. Click Pan Realtime from the Standard toolbar.

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REDRAW
AutoCAD redraws the current viewport, removing marker blips. It also displays artifacts
(stray pixels) left by editing commands. Type Redraw or just R at the command
prompt.
Use the Redraw command to:
• Refresh the display.
• Remove all graphics remnants such as blips, stray pixels, etc.
REGEN
The Regen and Redraw commands seem to have similar functions. Although their
functions appear to be similar, the Redraw and Regen commands are significantly
different. Type REGEN at command prompt:
• Regenerate entire drawing data.
• Recompute the screen coordinates.
• Reindex the drawing database for maximum performance (recreates the display

list).

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08 BLOCK, WBLOCK AND INSERT BLOCK

Drawing the resistor, transformer, and ceiling fan in previous workbook might have
taken what seemed to you an inordinate amount of time. As you continue to use
AutoCAD, however, you will learn to draw objects more quickly. You will also need to
draw fewer of them because you can save drawings as symbols and use them as
rubber stamps, duplicating drawings instantaneously wherever they are needed. This
saves a lot of time when you’re composing drawings. To make effective use of
AutoCAD, begin a symbol library of drawings you use frequently. A mechanical
designer might have a library of symbols for fasteners, cams, valves, or any type of
parts for their application. An electrical engineer might have a symbol library of
capacitors, resistors, switches, and the like. A circuit designer will have yet another
unique set of frequently used symbols.

Create a symbol library

BLOCK

To save a drawing as a symbol, you use the Block tool. In word processors, the term
block refers to a group of words or sentences selected for moving, saving, or deleting.
You can copy a block of text elsewhere within the same file, to other files, or to a
separate file or disk for future use. AutoCAD uses blocks in a similar fashion. Within a
file, you can turn parts of your drawing into blocks that can be saved and recalled at
any time. You can also use entire existing files as blocks. You’ll start by opening the
file you worked on in the last chapter and selecting the objects that will become a
block.
1. Start AutoCAD and open the existing Bath file. Use the one you created in, or

Assignment 3(electronic & electric).dwg on the floopy disk. Metric users can use
the Assignment 3(electronic & electric).dwg file. The drawing appears just as you
left it in the last session.
2.

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3. .In the Draw toolbar, click the Make Block tool or type B ↵ , the keyboard shortcut
for the Make Block tool, to open the Block Definition dialog box. You can also
choose Draw ↵ Block ↵ Make.

BLOCK

Block name : type name of block (resistor)
Base point : pick base point (use ENDpoint)

Select object : pick object
Block unit : select unit(millimeter)
4. Block command cannot be saved to your alternative drive.

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WBLOCK ( write block )
Using the WBLOCK command, you also can make your library automatically save to
your destination.
Command: WBLOCK ↵

WBLOCK

Base point : pick base point (use ENDpoint)
Select object : pick object (resistor)
Block unit : select millimeter

Destination : select path for destination file

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INSERT BLOCK

There are two methods of doing this.
5. Type INSERT at the command prompt. OR
6. Click Insert Block from the Draw toolbar.

INSERT

Browse file : resistor
Insertion point : pick point or coordinates

Scale : 1:1

MINSERT Rotation : 0

The MINSERT command (AutoCAD only) lets you insert blocks in a rectangular array.

There is one method of doing this.
1. Type MINSERT at the command prompt.

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Command: MINSERT
MINSERT Enter block name or [?]: D:\electronic component\resistor
Units: Millimeters Conversion: 1.0000
Specify insertion point or [Basepoint/Scale/X/Y/Z/Rotate]: pick point or coodinate
Enter X scale factor, specify opposite corner, or [Corner/XYZ] <1>: 1
Enter Y scale factor <use X scale factor>: 1
Specify rotation angle <0>: 0
Enter number of rows (---) <1>: 1
Enter number of columns (|||) <1>: 1

MINSERT prompts you for an insertion point, scale factors, and rotation angle using
the same prompts as the INSERT command, but without the dialog box. It then starts
the same prompts as the Rectangular option of the ARRAY command, asking for the
number of rows and columns and the distance between them. The value of MINSERT
is that it reduces the size of your drawing because the array is one block object. The
disadvantage is that you can’t edit the individual blocks in the array or the array as a
whole in any way. If you need to edit them, erase the entire array of blocks, redefine
the single block, if necessary, and start over, this time using INSERT and ARRAY
separately. You cannot explode a minsert block.

EXPLODE
You can explode blocks into their original objects. You may need to do this to edit a
block. If you want, you can then redefine the block. The insert block object cannot be
modified if that insert block object does not explode first.

There are two methods of doing this.
1. Type EXPLODE at the command prompt.
2. Click EXPLODE from the Modify toolbar.

Example :
Command: explode ↵
Select objects: pick object ( insert block object ) ↵
Select objects: ↵

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You can also explode polylines, dimensions, hatches, regions, multilines, and certain
3D objects (bodies, 3D meshes, 3D solids, various types of surfaces, polyface
meshes, and polygon meshes) into simpler types of objects. Exploding a block with
nested blocks explodes only the top-level
block. You need to use EXPLODE again to explode the next level of blocks. When you
explode blocks that were created on layer 0 or with BYBLOCK objects, the objects
return to their original status and appear black/white with a continuous linetype and
default lineweight again.
If you insert a block with different X and Y scales, the command does its best to create
objects based on their new shapes. For example, if you have a block that includes a
circle and insert it with an X scale of 1 and a Y scale of 2, you see an ellipse. Therefore,
when you explode the block, you get an ellipse from what used to be a circle.

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09 LAYER, LINETYPE AND COLOR

LAYER COMMANDS
The command line version of Layer creates new layers; sets the current layer; sets the
color, linetype, lineweight, and plot style for designated layers; turns layers on and off;
turns plotting on and off for visible layers; locks and unlocks layers; freezes and thaws
layers; and lists defined layers.
There are three methods of doing this.
1. Type Layer or just La at the command prompt.

2. Click the layers icon from the Object Properties toolbar.
You will see the Layer Properties Manager Dialog Box as shown below.
New
It creates a new layer. After you choose New, the list displays a layer named LAYER1.
You can edit this layer immediately. To create multiple layers more quickly, you can
select a layer name for editing and enter multiple layer names separated by commas.

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If you create a new layer, the new layer inherits the properties of the currently selected
layer in the layer list (Color, On/Off state, and so on). To create layers with default
settings, make sure that there are no selected layers in the list or that you select a
layer with default settings before beginning layer creation.
Current
Sets the selected layer as the current layer. The CLAYER system variable stores the
layer name.
Delete
Deletes selected layers from the drawing file definition. You can delete only
unreferenced layers. Referenced layers include layers 0 and DEFPOINTS, layers
containing objects (including objects in block definitions), the current layer, and xref-
dependent layers. Layers that do not contain objects (including objects in block
definitions), are not current, and are not xref-dependent can be deleted by using the
PURGE command.

Show/Hide Details
Controls whether the Details section is displayed in the Layer Properties Manager.
Save State
Displays the Save Layer States dialog box, in which you save layer state and layer
properties settings of all layers in a drawing. You can choose which layer states and
properties that you want to preserve. You save a layer state by assigning it a name.
Any layer states saved in a drawing that is inserted in your current drawing as a block
are also added to the current drawing.
Restore State
Displays the Layer States Manager, in which you can manage named layer states.
List of Layers
Displays layers and their properties. To modify a property, click its icon. To quickly
select all layers, right-click and use the shortcut menu.

• Names
Displays the names of the layers. You can select a name and then click and enter
a new name.

• On/Off

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Turns layers on and off. When a layer is on, it is visible and available for plotting.
When a layer is off, it is invisible and not plotted, even if the Plot is on.

• Freeze/Thaw in All Viewports
Freezes selected layers in all viewports. You can freeze layers to speed up ZOOM,
PAN, and many other operations; improve object selection performance, and
reduce regeneration time for complex drawings. AutoCAD does not display, plot,
hide, render, or regenerate objects on frozen layers. Freezes the layers you want
to be invisible for long periods. When you thaw a frozen layer, AutoCAD
regenerates and displays the objects on that layer. If you plan to switch between
visible and invisible states frequently, use the On/Off setting. You can freeze layers
in all viewports, in the current layout viewport, or in new layout viewports as they
are created.

• Lock/Unlock
Locks and unlocks the layers. You cannot edit objects on a locked layer. Locking
a layer is useful if you want to view information on a layer for reference but do not
want to edit objects on that layer.

• Color
Changes the color associated with the selected layers. Clicking the color name
displays the Select Color dialog box.

• Linetype
Changes the linetype associated with the selected layers. Clicking any linetype
name displays the Select Linetype dialog box.

• Lineweight
Changes the lineweight associated with the selected layers. Clicking any lineweight
name displays the Lineweight dialog box.

• Plot Style
Displays a list of plot styles available to apply to the selected layers. If you are
working with color-dependent plot styles (the PSTYLEPOLICY system variable is
set to 1), you cannot change the plot style associated with a layer. The default plot
style is Normal.

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HOW TO SET LINETYPES AND COLOR
You can use color to help you group objects visually. You can assign the color of an
object either by layer or by specifying its color explicitly, independent of a layer.
Assigning colors by layer makes it easy to identify each layer within your drawing.
Assigning colors explicitly provides additional distinctions between objects on the
same layer.
Linetype
To load a linetype
1. From the Format menu, choose Linetype.
2. In the Linetype Manager, choose Load.

3. In the Load or Reload Linetypes dialog box, select a linetype and choose OK.

If the linetype you need is not listed, choose File. In the Select Linetype File dialog
box, select a LIN file whose linetypes you want to list and choose Open. The dialog

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box displays the linetype definitions stored in the selected LIN file. Select a linetype
and choose OK.
To list the linetypes loaded in the current drawing
1. On the Object Properties toolbar, click the Linetype control.

All loaded linetypes are displayed in the list. If necessary, use the scroll bar to see
the whole list.
2. Click anywhere outside the box to close it.

Colors
To set the color for all new objects
1. On the drop-down icon below;

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Color control displays the current color.
To change the color of an object, overriding the layer's color
1. On the Standard toolbar, click Properties.
2. Select the objects whose color you want to change.
3. In the Properties window, select Color.
To change the color assigned to a layer
1. On the Object Properties toolbar, click Layers.
2. In the Layer Properties Manager, click the color you want to change.
3. In the Select Color dialog box, click a color or enter a color number (1-255) or

name.
4. Choose OK to exit each dialog box. An arrow is displayed in the right column.
4. Click the arrow and select a color from the list.

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10 DIMENSIONING

IMPORTANCE AND BENEFITS OF DIMENSIONING DRAWINGS
Dimensioning is the process of adding measurements to a drawing. Dimensions show
the geometric measurements of objects, distances or angles between objects or the
X and Y coordinates of a feature. Every dimension style controls colour, text style and
linetype scale.
Dimensioning is the process of adding measurement annotation to a drawing.
AutoCAD provides many ways to dimension objects and many ways to format
dimensions. You can create dimensions for a wide variety of object shapes in many
different orientations. You can create dimension styles to format dimensions quickly
and ensure that dimensions in your drawing conform to industry or project standards.
Dimensions show the measurements of objects, the distances or angles between
objects, or the distance of a feature from an origin you specify. AutoCAD provides
three basic types of dimensioning: linear, radial, and angular. Dimensions can be
horizontal, vertical, aligned, rotated, ordinate, baseline, or continued.
You can dimension objects, such as lines, arcs, circles, and polyline segments, or you
can dimension between point locations.
AutoCAD places dimensions on the current layer. Every dimension assumes the
current dimension style, which controls characteristics such as arrowhead style, text
location, and lateral tolerances. With dimension styles, you can make subtle
modifications to a base dimension style for different types of dimensions. With
dimension style overrides, you can modify these characteristics for a specific
dimension.

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Origin point is an origin point defines the measurement value for the dimension text
and is a small nonprinting point attached to the dimension. Origin points are typically
placed on an object and allow you to move or reposition a dimension that may need
to be updated.

Extension line is an extension line extends up to the dimension line and arrowheads
and indicates which feature or points on an object are being dimensioned. An
extension line typically has a gap between it and the origin point of the dimension
object and extends past the dimension line. The gap helps show that the dimension is
not part of the object.

Arrowhead is an arrowhead appears at the end of a dimension line and indicates
where a dimension starts and ends. Arrowheads can be displayed as open or closed
arrows, architectural ticks, dots, or user defined arrows, among other arrowhead
styles.

Dimension line is a dimension line is typically displayed between the extension lines
and goes outward from the center of the dimension object toward the extension line.
Based on where the dimension text is placed, the dimension line may appear broken
or on the outside of the extension lines.

Dimension text is a dimension text provides the value of measurement with which the
dimension was created and can be formatted in a variety of ways. Some of the
formatting options are the units of measurement, the type of decimal separator that is
used, and how the value should be rounded.

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Click Annotate to make dimension

LINEAR
There are two methods of doing this.

1. Type DIMLINEAR 0r
2. Click Linear icon

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Example :
Command: _dimlinear
Specify first extension line origin or <select object>: pick 1st line origin
Specify second extension line origin: pick 2nd line origin
Specify dimension line location or [Mtext/Text/Angle/Horizontal/Vertical/Rotated]:
Specify dimension line location or [Mtext/Text/Angle/Horizontal/Vertical/Rotated]:
Dimension text = 10

RADIUS

Example :

Command: _dimradius
Select arc or circle:
Dimension text = 6
Specify dimension line location or [Mtext/Text/Angle]: M
Specify dimension line location or [Mtext/Text/Angle]:

DIAMETER

Command: _dimdiameter
Select arc or circle:
Dimension text = 20
Specify dimension line location or [Mtext/Text/Angle]: M
Specify dimension line location or [Mtext/Text/Angle]:

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ALIGNED

Example :

Command: _dimaligned
Specify first extension line origin or <select object>:
Specify second extension line origin:
Specify dimension line location or
[Mtext/Text/Angle]: M
Specify dimension line location or
[Mtext/Text/Angle]:
Dimension text = 8

ANGULAR

Example :
Command: _dimangular
Select arc, circle, line, or <specify vertex>: pick 1st line
Select second line: pick 2nd line
Specify dimension arc line location or [Mtext/Text/Angle/Quadrant]:
Dimension text = 28

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DIM STYLE AND VARIABLE
You can control the appearance of dimensions by changing settings. For convenience
and to help maintain dimensioning standards, you can store these settings in
dimension styles.
There are two methods of doing this.

1. Type Dimstyle at command prompt or
2. Click Format >> Dimension Style from the pull-down menu bar.

Set Current
Sets the style selected under Styles to current.
New
Displays the Create New Dimension Style dialog box, in which you can define new
dimension styles. See New, Modify, and Override Dimension Style Dialog Boxes.

Click New to open the Create New Dimension Style dialog box above. With the copy
name highlighted in the New Style Name input box, enter a new name for your style.
Check to make sure your dimension style name conforms to any standards that other
members of the team might be using.

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Modify
Displays the Modify Dimension Styles dialog box, in which you can modify dimension
styles. Dialog box options are identical to those in the New Dimension Style dialog
box. See New, Modify, and Override Dimension Style Dialog Boxes.
Override
Displays the Override Current Style dialog box, in which you can set temporary
overrides to dimension styles. Dialog box options are identical to those in the New
Dimension Style dialog box. See New, Modify, and Override Dimension Style Dialog
Boxes. AutoCAD displays override as unsaved changes under the dimension in the
Styles list.
Compare
Displays the Compare Dimension Styles dialog box, which compares the properties of
two dimension styles or lists all the properties of one style.
Click Modify from Dimension Style Manager. You can see as shown below.

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New Dimension Style dialog box.

From this dialog box, we can change:
i. Lines and Arrows
ii. Text
iii. Fit
iv. Primary Units
v. Alternate Units
vi. Tolerances

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11 PLOTTING

PREPARATORY STEPS FOR PLOTTING
Once you have completed a drawing, you can use a number of methods to output the
drawing. You can plot the drawing on paper or create a file for use with another
application. In either case, you select the plot settings.
There are two methods of plotting.
1. Type Plot at the command prompt.
2. Click Plot from the Output Toolbar.

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3. The dialog box appears shown above.
To plot a drawing
From the File menu, choose Plot.
1. In the Plot dialog box.

i. Select a printer or plotter name that wants to use.
ii. Select paper size of printer/plotter for example – A2, A3 or A4.
iii. Drop down plot area – select display, extents, limits or window.
iv. At plot scale –choose fit to paper or custom scale.
v. Plot offset – origin set to a printable area ( x and y coordinate ) or center the

plot.
vi. Put the number of copies.
vii. Press OK.

PLOT AREA
When plotting a drawing, you must specify the area of the drawing to plot. The Plot
Settings tab in the Plot dialog box provides six options under Plot Area.
Layout or Limits
When plotting a layout, this option plots everything within the margins of the specified
paper size, with the origin calculated from 0,0 in the layout. When plotting on the Model
tab, it plots the entire drawing area defined by the drawing limits. If the current viewport
does not display a plan view, this option has the same effect as the Extents option.
Extents
Plots the portion of the current space of the drawing that contains objects. All geometry
in the current space is plotted. AutoCAD may regenerate the drawing to recalculate
the extents before plotting.

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Display
Plots the view in the current viewport in the Model tab or the current paper space view
in a layout tab.
View
Plots a view saved previously with the VIEW command. You can select a named view
from the list provided. If there are no saved views in the drawing, this option is
unavailable.
Window
Plots any portion of the drawing you specify. Click the Window button to use a pointing
device to specify opposite corners of the area to be plotted or enter coordinate values.

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REFERENCES

1. Autodesk (2014) AutoCAD 2014 : User’s guide
2. Khairul Anuar Hanfiah (1996) Lukisan Kejuruteraan Berbantu

Komputer Skudai : Universiti Teknologi Malaysia
3. http://en.wikipedia.org/wiki/Electronic_symbol
4. https://www.rapidtables.com/electric/electrical_symbols.htm
5. http://www.rapidtables.com/electric/Electronic_components.htm
6. http://lukisankejuruteraankvkk.blogspot.com/2014/03/lukisan-simbol-

elektrik-dan-elektronik.html

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