AutoCAD 2D Tutorials

27-3-2019

Lecturer: Saad Thanoon

TECHNICAL COLLEGE OF ENGINEERING

Engineering Drawing and AutoCAD

Contents

Outline (Modifying commands )

Class work

Offset

Array ( Rectangular ,Polar, Path)

Scale

Home work

Stretch

Explode

• Offset: Offset creates a line or curve parallel to an existing object.

• In order to apply it, offset distance must be specified. you can specify it by typing the

distance in or clicking two points on screen.

• After entering the distance, grab an object to offset and click on the side that you want

to offset it to.

• You can offset an object multiple times in the same distance by repeating click.

• TIP An effective drawing technique is to offset objects and then trim or extend their

ends.

Outline (Modifying commands )

● Array ( Rectangular ,Polar, path)

• Array Objects Create multiple copies of objects that are evenly distributed in

a rectangular or circular pattern, or along a specified path.

• There are three different array commands: rectangular, polar, and path.

Outline (Modifying commands )

●Create Rectangular Arrays:

• In rectangular arrays, items are distributed into any combination of rows, columns, and levels. A dynamic preview allows you to quickly derive the number and spacing of rows and columns. Add levels to make a 3D array.

● You can modify, erase, or transform individual items in an array using the Ctrl key to select the desired objects. You can then use familiar AutoCAD editing tools to erase, move, rotate, or scale those selected objects.

• Associative. Items are contained in a single array object, similar to a block. Edit an item’s source objects to change all items that reference those source objects.

• Non-associative. Items in the array are created as independent objects. Changes to one item do not affect the other items.

Outline (Modifying commands )

● Create Polar Arrays : In polar arrays, items are evenly distributed about a center point or axis of rotation.

- Center point of array; Specifies the central location for the array.

- Base Point; Specifies a new reference (base) point relative to the selected objects that will remain at a constant distance from the center point of the array as the objects are arrayed.

- Number of items in the array; Specifies the total number of items to be arrayed around the center point.

- Angle between items ;Specifies the included angle between objects, based on the center point of the array and the base points of the arrayed objects.

- Angle to fill :Specifies the included angle between the base points of the first and last arrayed objects.

- Rotate items controls whether items are rotated as they are arrayed.

Outline (Modifying commands )

● Create Path Arrays: In path arrays, items are evenly distributed

along a path or a portion of a path. A path can be a line, polyline, 3D

polyline, spline, helix, arc, circle, or ellipse.

Outline (Modifying commands )

• Method (Path Arrays)

• Controls how to distribute items along the path.

• ■ Divide. Redistributes items to divide evenly along the length of the path.

• ■ Measure. Maintains current spacing when the path is edited, or when the number of

items is edited through grips or the Properties Inspector. When the number of items is

edited using ARRAYEDIT, you are prompted to redefine the distribution method.

• Align Items (Path Arrays)

• Specifies whether to align each item to be tangent to the path direction.

Outline (Modifying commands )

• Scale: This command allows the user to enlarge or reduce an object or

group of objects. The user must select the object(s) and a base point. The

user then can type in an enlargement factor (i.e. 2) or a reduction factor (i.e.

0.5).

• you can also scale objects by the relative distances using “Reference” points.

• select objects, click/type a base point, then type “r” for Reference. click the

base point again, then click the second point to define the original distance.

click the third point at where you wish the previous point to be after scaling

objects.

• In this way, it will scale the objects by the distance ratio of base point to

the second point : base point to the third point. Position of the base

point needs to be constant.

Outline (Modifying commands )

● Stretch Object can be made longer or shorter with STRETCH.

• Objects that are partially enclosed by a crossing window are stretched.

Objects that are completely enclosed within the crossing window, or that are

selected individually, are moved rather than stretched. Several objects such

as circles, ellipses, and blocks, cannot be stretched.

• STRETCH moves only the vertices and endpoints that lie inside the crossing

selection, leaving those outside unchanged. STRETCH does not modify 3D

solids, polyline width, tangent, or curve-fitting information.

Outline (Modifying commands )

• Explode: This command is essentially an undo button for blocks. After entering this

command, AutoCAD will ask for an object to explode. The chosen object will return to

being a series of individual objects, just like it was before it was turned into a block.

• break selected complex objects such as blocks and polylines down to lines and arcs.

• To disassemble a complex object, such as a block, dimension, solid, or polyline,

• into simpler objects. In the case of a block, the block definition is unchanged.

• The block reference is replaced by the components of the block. See also block,

• block definition, and block reference. (EXPLODE)

Outline (Modifying commands )

Exercises ( Homework)

• 1

Exercises ( class work)

Exercises ( Homework)

• 4