MODULE HATCHING 29 - Weebly · 2018-10-02 · AutoCAD 2D III 33 Module 29: Hatching HATCHING MODULE...

AutoCAD 2D III Module 29: Hatching 33

HATCHING

MODULE

29

Sections

Why are Sectional Views Important?

An orthographic projection of a product will show the exterior surfaces. Interior details are hidden and are represented with the hidden-line. If the hidden

features are complex, these hidden lines do not show them clearly. In such

cases, a sectional view is drawn.

LEARNING OUTCOME

After the completion of this module, you will be able to:

• Explain sectional views, sections, and hatching in sectional views.

• Describe and apply the BHATCH, HATCHEDIT, and SNAPBASE

commands to insert and edit hatching pattern into drawing.

Arrows show the direction you look for section view.

Cutting plane line

Institute of Applied Technology ®


A sectional view frequently replaces one of the regular views. For example, a

regular front view is replaced by a front section (see below).

TOP VIEW

FRON T VIEW

SECTION VIEW

TOP VIEW

Arrows show direction

Cutting plane line

Crosshatching



Hatching Patterns

Section lining, sometimes referred to as cross-hatching, is used to indicate

material in the sectioned part.

Most often, the general-purpose cross hatching symbol is used to represent

any material.

General-purpose

crosshatching symbol for any material

There are also several other types of crosshatching symbols used to represent

a wide variety of materials. A few are illustrated below.

Define the Boundaries of a Hatch

You can choose from several methods to specify the boundaries of a hatch.

• Specify a point in an area that is enclosed by objects.

• Select objects that enclose an area.

• Drag a hatch pattern into an enclosed area from a tool palette or

DesignCenter. (This will be discussed later in this course)

Using the BHATCH command

Steel Concrete Bricks Concrete



The BHATCH command is used to insert hatch patterns inside a boundary.

You can start the command using one of the following methods.

Command Keyboard input / Alias Icon Menu

BHATCH Bhatch / Hatch / H

Draw > Hatch

The BHATCH command opens the Hatch and Gradient dialogue box.



The Hatch Type

Defines the appearance of the hatch pattern to be applied.

Type and Pattern Type In this option, you can choose the type,

three options are available:

1- Predefined

2- User defined

3- Custom

We will use Predefined at this level. Pattern

Lists the available predefined patterns.

The Pattern option is available only if

you set Type to Predefined.

Pressing this button next to

Pattern the “Hatch Pattern Palette”

dialogue box will open.

Swatch

Displays a preview of the selected

hatch pattern. You can click the

swatch to display the Hatch Pattern Palette dialog box.

Use the tabs available in the Hatch Pattern Palette dialogue box to display the

different patterns available.



Angle and scale

Angle

Specifies an angle for the hatch

pattern relative to the X-axis of the

current UCS.

Scale

Expands or contracts a predefined or

custom pattern. This option is available

only if you set Type to Predefined or Custom.

Exercise 1: Create a new file using acadiso.dwt template. Draw a rectangle of a suitable size (use the rectangle command) and hatch it using the Pattern ANSI31.

Command: H HATCH (Click this button to Pick points) Pick internal point or [Select objects/remove Boundaries]: Selecting everything... Selecting everything visible... Analyzing the selected data... Analyzing internal islands... Pick internal point or [Select objects/remove Boundaries]: P1 (Select any point inside the rectangle and click OK in the Hatch dialogue box)



Exercise 2: Draw another rectangle and hatch it using the Select Objects option. Use the Pattern ANSI32. Command: Hatch (Click this button to select objects) (Select the rectangle) Select objects or [picK internal point/remove Boundaries]: P1 1 found (AutoCAD will tell you how many objects found) Select objects or [picK internal point/remove Boundaries]: (Click OK to accept the hatching) Exercise 3: Draw two circles of suitable sizes. Use the hatch pattern ISO04W100 to fill in the first circle. For the second circle use the same pattern but change the angle to 30º and the scale to 0.5.

ISO04W100 (angle 0, scale 1) ISO04W100 (angle 30, scale 0.5)



Command: _bhatch (Select Pattern to be ISO04W100) (Keep the values of the Angle and Scale as shown) Pick internal point or [Select objects/remove Boundaries]: Selecting everything... Selecting everything visible... Analyzing the selected data... Analyzing internal islands... (Select the circle) Pick internal point or [Select objects/remove Boundaries]: (Click OK to accept the hatching) Command: BHATCH (Select Pattern to be ISO04W100) (Change the values of the Angle and Scale as shown) Pick internal point or [Select objects/remove Boundaries]: Selecting everything... Selecting everything visible... Analyzing the selected data... Analyzing internal islands... (Select the circle) Pick internal point or [Select objects/remove Boundaries]: (Click OK to accept the hatching)

Options Controls several commonly used hatch or fill options.

Associative

A hatch that is associative is updated when you

modify its boundaries.



Exercise 4: Use the drawing in exercise 1 and stretch it as shown below.

Exercise 5: Use the same object from exercise 4 and change the properties of

the hatch to non-associative and stretch the

object.

Before stretching After stretching

As you realized, when you stretched the object the Hatch moved with the object boundary and filled the whole area. Remember that when we hatch this object the Associative option was chosen.

Change the properties to non-associative then stretch the object as shown below.

Because of the non-associative option, the hatched area stays as is.



When the Create Separate Hatches option is checked,

Four separate hatches are created as

shown.

When the Create Separate Hatches option is not checked,

One hatch is created as shown.

Create Separate Hatches

Controls whether a single hatch object or multiple hatch objects are created

when several separate closed boundaries are specified.

Exercise 6: Draw an object similar to the one shown below and hatch it once

when the Create Separate Hatches option is checked and another when it is

not checked.



Islands

Exercise 6: Draw an object similar to the one shown below and hatch it using

the three Island display styles.

The drawing you created should look like the drawings below.

Note that the text is considered as a island and it is hatched according to the island style you are using.



Exercise 7: Copy the object from exercise 6 and use normal island style, then

use the Remove Boundary option in order not to hatch the circle.

Command: _bhatch Pick internal point or [Select objects/remove Boundaries]: P1 (Select an internal point)

Selecting everything... Selecting everything visible... Analyzing the selected data... Analyzing internal islands... Pick internal point or [Select objects/remove Boundaries]: B (Select B to remove boundary) Select objects or [Add boundaries]: P2 (Select the circle) Select objects or [Add boundaries/Undo]: (Press enter) Select objects or [Add boundaries/Undo]: (Click OK)



Using the HATCHEDIT command

The Hatchedit command modifies an existing hatch or fill. To start the

command you can the following methods.

Exercise 8: Copy the object in exercise 7 and use the edit command to change

the pattern from ANSI31 to ANSI 37. Use the Preview option to see the change

before accepting it.

Command: HE

HATCHEDIT

Select hatch object:

(Select the hatch)

(Change the pattern to ANSI37)

Command Keyboard input Icon Menu

Hatchedit Hatchedit / HE

Modify>Object> Hatch

Before After

ANSI

stands for American National Standards

Institute



(Click preview)

Pick or press Esc to return to dialog or <Right-click to accept hatch>:

(Press ESC if you want to go back to the Hatch Edit dialogue or Right-click to

accept hatch box to accept)

Exercise 8: Copy the object in exercise 7 and use the edit command to change

the pattern from ANSI31 to SOLID then change the color to yellow.

Command: _hatchedit

Select hatch object:

(Select the hatch object and change the Pattern

and the color)

Before After

FILL command can be used to

control the fill of the hatching

pattern



Exercise 9: Draw an object similar to the one shown below. Hatch it using the

pattern AR B816. Copy your drawing and use HatchEdit to change the hatch

origin to have a hatch pattern similar to the one shown in figure 2.

As you can see, the hatch location in the object at left is not proper. To modify this, use the Hatchedit command to change the origin of the hatch to a new position. In the Hatch edit dialogue box click the button “Click to set new origin” and use the indicated point as the new origin.

Before changing the origin After changing the origin New origin

SNAPBASE system variable

The SNAPBASE system variable sets the snap and grid origin point for the current viewport relative to the current UCS. It is also used to change the origin point for hatching pattern.

Command line: SNAPBASE

EXPLODE command can be used to change

the hatch from one object to individual

objects



TASK 1 DETAILS

Instructions:

1. Draw the top and front views of the object. 2. Draw a section view as shown by the cutting plane. 3. Use hatching pattern ANSI31.

Lab Exercise 29-1 Time Allotted: 50 min.

Drawing Specifications

Name Template Units Text Style Font

AutoCAD 2D Lab 29-1 Module Template A Inches N/A N/A

Layering Scheme

Objects on Layer Name Color Linetype Lineweight

Construction Objects Construction 253 Continuous N/A

All Objects Object Red Continuous N/A

Centerlines Center Green Continuous N/A

Hatch Patterns Hatch 200 Continuous N/A



Module 29 Review Questions

1. Section lining or crosshatching is also known as a ______. a. section pattern

b. section-line pattern

c. phantom-line pattern

d. hatch pattern

2. When half of the object is cut and removed on a drawing, the result is a _________.

a. half section

b. quarter section

c. 3 full section

d. removed section

3. Sectional views are defined or located using a _________. a. cutting-plane line.

b. 4 phantom line

c. 3 visible line

d. 2 phantom plane

4. What system variable controls the origin of a hatch pattern? a. RECTANG

b. PEDIT

c. SNAPBASE

d. POLYLINE

5. What two commands are used to toggle the hatching pattern display on or off in a drawing?

a. FILL and PEDIT

b. FILL and EXPLODE

c. FILL and REGENERATE

d. FILL and REDRAW



6. Which on of the following objects can be exploded? a. A circle

b. An Ellipse.

c. A hatch

d. A single line

7. ANSI stands for ____________. a. American National Standards Institute

b. American National Society Institute

c. American National Standards Internet

d. AutoCAD National Standards Institute

8. A(n) ________ hatch will automatically adjust when the boundary that was used when it was inserted is moved or changed.

a. non-associative

b. associative

c. snapbased

d. None of the above.

9. A non-associative hatch can be changed to associative hatch by using the _________ command.

a. PEDIT

b. PROPERTIES

c. EXPLODE

d. FILL

10. You hatched a boundary and you couldn’t see the hatching. Which hatching property you must change to make the hatching pattern visible?

a. The Scale

b. The Angle

c. The Origin

d. The width

MODULE HATCHING 29 - Weebly · 2018-10-02 · AutoCAD 2D III 33 Module 29: Hatching HATCHING MODULE...

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