Print Reading: CAD Symbol Libraries - Isbe

Print Reading: CAD Symbol Libraries Unit: Graphic Agility Problem Area: Print Reading—Lines and Symbols Lesson: Print Reading: CAD Symbol Libraries Student Learning Objectives. Instruction in this lesson should result in students achieving the following objectives: 1 2 3 Review CAD symbol block creation. Use CAD blocks. Create CAD symbol libraries. Resources. The following resources may be useful in teaching this lesson: cadalyst. Accessed Oct. 7, 2012. http://cadtips.cadalyst.com/tool-palettes/ store-your-block-library-tool-palettes. Cad notes. Accessed Oct. 7, 2012. http://cad-notes.com/2011/02/ whats-new-in-autocad-block-and-references/. MyCADSite. Accessed Oct. 7, 2102. http://www.we-r-here.com/cad/tutorials/ level 2/2-2.htm. Grabowski, Ralph. The Illustrated AutoCAD 2012 Quick Reference Guide. Delmar Cengage, 2012. Moss, Elise. Autodesk AutoCAD 2013 Fundamentals. SDC, 2012. Lesson: Print Reading: CAD Symbol Libraries Page 1 u www.MyCAERT.com Copyright by CAERT, Inc. Reproduction by subscription only. L600103

Equipment, Tools, Supplies, and Facilities ü Overhead or PowerPoint projector ü Visual(s) from accompanying master(s) ü Copies of sample test, lab sheet(s), and/or other items designed for duplication ü Materials listed on duplicated items ü Computers with printers and Internet access ü Classroom resource and reference materials Key Terms. The following terms are presented in this lesson (shown in bold italics): Block Definition CAD Block Editor CAD block CAD symbol library Write Block Interest Approach. Use an interest approach that will prepare the students for the lesson. Teachers often develop approaches for their unique class and student situations. A possible approach is included here. Creating blocks is one of the most useful functions in CAD. Using blocks can save so much time. They are easy to make and can be used many times. Show students some examples of CAD blocks you have created. Demonstrate how you use them in drawings. CONTENT SUMMARY AND TEACHING STRATEGIES Objective 1: Review CAD symbol block creation. Anticipated Problem: How are CAD symbol blocks created? I. CAD symbol block creation A. A CAD block is a set of lines, text, and geometries grouped together with a set of properties. A block can be saved in a folder or library and used many times. There are internal and external blocks. 1. Internal blocks are blocks defined within a specific drawing and are only used in that drawing. Lesson: Print Reading: CAD Symbol Libraries Page 2 u www.MyCAERT.com Copyright by CAERT, Inc. Reproduction by subscription only. L600103

2. External blocks are saved as separate files, just like any other drawing file, with an insertion base point. They may be used in any drawing. If a change is made to the original block, it is updated everywhere it is used in a drawing. An existing object (e.g., a chair) can be converted into a block. There are several ways to create blocks in CAD. B. Block definition 1. Creating a Block Definition (a set of attributes that define the block) is one way to create a CAD block. Once an object is drawn, the word “block” is typed into the command prompt window. 2. In the Block Definition window, there are several headings (or topics) that may be defined, including the base point, the objects to be created into a block, settings (e.g., units), and some additional behaviors. Then a name is given to the block. Naming is necessary so the block can be saved and used later. The objects that create the block are selected after the block is named. 3. Under the Objects heading, it is necessary to choose “Select Objects.” The objects are selected from the drawing space. Several more options may be selected in this heading: a. The Retain option creates and stores the block, but the original object in the drawing will remain as separate lines, not a block. b. The Convert to Block option creates the block and coverts the object in the drawing into a block. c. The Delete option creates the block and then deletes the object in the drawing. 4. The OK or Close button is selected to create the actual block. For additional special definitions (e.g., the base point), the coordinates can be given or the option to Specify On-Screen can be selected. The base point is the exact point on the object (block) used as a reference when it is inserted into a drawing. 5. Block Definitions can be changed at any time in the future. The block is saved in a pre-determined folder in the software. C. Create tab 1. Another way to create a block is by selecting the Create tab on the Block ribbon. This opens the Block Definition window. 2. Then the same steps as for the Block Definition above are followed to complete the block. Teaching Strategy: Use VM–A and VM–B. Demonstrate the creation of a CAD symbol block for the students. Assign LS–A. Lesson: Print Reading: CAD Symbol Libraries Page 3 u www.MyCAERT.com Copyright by CAERT, Inc. Reproduction by subscription only. L600103

Objective 2: Use CAD blocks. Anticipated Problem: How are CAD blocks used? II. Using CAD blocks—Frequently, drafters and designers need a set of pre-drawn symbols (e.g., blueprint schematic symbols) for engineering or piping projects. Using CAD blocks of pre-drawn symbols can make drawing time more efficient. Any symbol, object, or tag that is used repeatedly should be saved and used as a block. Blocks can be inserted into any drawing and their orientation can be changed to fit specific parts of a drawing. If blocks are given parametric attributes, their size, orientation, and attributes can be changed. There are several ways to place a CAD block. A. In the command prompt window, the word “insert” is typed, and the “Insert” window appears. The correct block must be chosen under the Name heading. The arrow can be selected, and a list of blocks appears. There is also the option to browse other locations in the computer or on a server. B. Several other headings in the window include Insertion Point, Scale, and Rotation. The block units will also be shown. It is important that the block units match the drawing units. The Insertion Point is the location in the drawing in which the block is to be placed. The coordinates can be typed in, or the option to Specify OnScreen can be selected. By selecting the Specify On-Screen option, the block can be placed anywhere in the drawing. The Scale heading allows the size of the block to be changed. The scale in the X-, Y-, and Z-axis may be given, or the scale can be Specified On-Screen. Therefore, once the block is placed in the drawing, the scale can be input. The Rotation heading is similar. The angle to rotate the block can be pre-set, or once the block is placed, it may be rotated. C. The default settings for all these headings allow the block to be placed anywhere in the drawing by use of the Specify On-Screen option. The default settings do not change the block’s scale or rotation. It is recommended that beginners use the default settings. D. To insert the block, select the OK or Close button. The exact point to insert the block is selected once the window is closed. E. The block can be moved, rotated, and mirrored at any time. When changes need to be made to one specific block, that block can be exploded. Once exploded, the block goes back to its original separated elements. F. When changes need to be made to all the blocks, the CAD Block Editor (a program that allows changes to be made to a block) can be used. Changes are made to the original file. Once the changes are saved, all the inserted blocks in a drawing are updated. To use the CAD Block Editor, the word “bedit” is typed into the command prompt window, or the Edit tab on the Block Editor Ribbon may be selected. Teaching Strategy: Use VM–C. Demonstrate how to use CAD blocks. Lesson: Print Reading: CAD Symbol Libraries Page 4 u www.MyCAERT.com Copyright by CAERT, Inc. Reproduction by subscription only. L600103

Objective 3: Create CAD symbol libraries. Anticipated Problem: How are CAD symbol libraries created? III. CAD symbol libraries A. A CAD symbol library is an organized collection of blocks. The library can include symbols for equipment and furniture, drawing elements, and tags. Symbols are grouped in folders according to subject matter. It is easy to manage and use symbol libraries in CAD. The Write Block function is a program in CAD that allows a person to create and organize the libraries. This function can be used with an existing block, or it can create a new one. 1. Typing “wblock” into the command prompt window accesses the Write Block program. The Write Block window appears with several heading choices, including Source, Base point, Destination, and Objects. 2. Under the “Source” heading, an existing block can be picked from the scrolldown menu. The file name and folder (or path) is created once the correct block is chosen. 3. The “Base point” is the exact point on the object (block) used as a reference when it is inserted into a drawing. 4. Under the “Destination” heading, the correct folder is selected. The existing name of the block is selected by default. If needed, the name can be changed. The OK or Close button is clicked to save the block in the correct path. 5. Under the “Source” heading, the Objects option is selected to create a new simple block. Next, objects are selected from the drawing for the new block. Once the objects from the drawing are selected, the same steps as above are followed. B. Folders 1. A well-organized set of folders helps manage a CAD library. 2. Folders are grouped for each type of symbol and block used. a. When working on an electronics plan, there could be a general folder for resistors and a series of subfolders for the various types of resistors. b. When working on an architectural plan, there could be a general folder for windows, a series of subfolders for windows in elevation, and windows in plan. Teaching Strategy: Use VM–D. Demonstrate how to create a library of CAD symbols. Assign LS–B. Review/Summary. Use the student learning objectives to summarize the lesson. Have students explain the content associated with each objective. Student responses can be used in determining which objectives need to be reviewed or taught from a different angle. Questions at the ends of chapters in the textbook may be used in the Review/Summary. Lesson: Print Reading: CAD Symbol Libraries Page 5 u www.MyCAERT.com Copyright by CAERT, Inc. Reproduction by subscription only. L600103

Application. Use the included visual master(s) and lab sheet(s) to apply the information presented in the lesson. Evaluation. Evaluation should focus on student achievement of the objectives for the lesson. Various techniques can be used, such as student performance on the application activities. A sample written test is provided. Answers to Sample Test: Part One: Completion 1. 2. 3. 4. 5. 6. CAD Block Editor Write Block Block Definition CAD block efficient (quicker) Create Part Two: True/False 1. 2. 3. 4. 5. 6. T F T T F T Part Three: Short Answer The four “Write Block” headings and a brief description are: a. Source—Under the “Source” heading, an existing block can be picked from the scroll-down menu. b. Base point—The base point is the exact point on the object (block) used as a reference when it is inserted into a drawing. c. Destination—Under the “Destination” heading, the correct folder (or path) is selected. d. Objects—Under the “Source” heading, the Objects option is selected to create a new simple block. Next, objects are selected from the drawing for the new block. Lesson: Print Reading: CAD Symbol Libraries Page 6 u www.MyCAERT.com Copyright by CAERT, Inc. Reproduction by subscription only. L600103