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NOTE Most of the commands used for dimensioning are prefaced with a dim when you enter them at the command line; that is the name of the com- mand. For example, when you click the Radius button on the Dimension tool- bar or choose Dimension ➣ Radius from the menu bar, you see _dimradius in the Command window to let you know that you have started the Dimradius command. You can also start this command by entering dimradius↵ or dra↵ (the command alias). 3. Click the inside arc of the balcony a slight distance above the mid- point. The radial dimension appears in dashed form. Where you pick the arc determines its angle of orientation. The dimension text then stays attached to the cursor (see Figure 12.25). FIGURE 12.25: The radial dimension initially positioned in the arc 4. Notice that the tick mark used for linear dimensions is used here also. You should have an arrowhead for the radial dimension. Press Esc to cancel the command. You’ll have to alter the dimension style to specify an arrowhead for radial dimensions. Using Other Types of Dimensions 487 26531ch12.qxd 4/3/07 7:24 PM Page 487 Setting Up Parent and Child Dimensioning Styles The DimPlan dimension style that you set up at the beginning of this chapter applies to all dimensions and is called the parent dimension style. But you can change settings in this dimension style for particular types of dimensions, such as the radial type, for example. This makes a child dimension style. The child version is based on the parent version, but it has a few settings that are different. In this way, all your dimensions will be made using the DimPlan dimension style, but radial dimensions will use a child version of the style. Once you create a child dimension style from the parent style, you refer to both styles by the same name, and you call them a dimension style family. Follow these steps to set up a child dimension for radial dimensions: 1. Click the Dimension Style button on the Dimension toolbar to open the Dimension Style Manager dialog box. It looks like Figure 12.26. FIGURE 12.26: The Dimension Style Manager dialog box with DimPlan current TIP When the Dimension toolbar is docked to either side of the drawing area, the Dim Style Control drop-down list does not display.You can, however, change the current dimension style from the Styles toolbar. 2. Be sure DimPlan is highlighted in the Styles list, and then click the New button to open the Create New Dimension Style dialog box. Chapter 12 • Dimensioning a Drawing488 26531ch12.qxd 4/3/07 7:24 PM Page 488 3. Open the Use For drop-down list, and select Radius Dimensions. Then, click the Continue button. The New Dimension Style dialog box opens and has the seven tabs you worked with earlier. Its title bar now includes Radial, and the preview window shows a radial dimension. 4. Activate the Symbols And Arrows tab. Then, move to the Arrowheads area, and open the second Arrowhead drop-down list. 5. Select Right Angle. Notice how the preview window now illustrates a radial dimension with a right-angle arrowhead. 6. Click the Text tab. 7. In the Text Placement area, open the Vertical drop-down list, and select Centered. 8. Click OK to close the New Dimension Style: DimPlan: Radial dialog box. 9. In the Dimension Style Manager dialog box, notice the Styles list. Radial is now a child style of the parent style DimPlan (see Figure 12.27). Click Close to close the Dimension Style Manager dialog box. FIGURE 12.27: Radial child dimension style in the DimPlan family Using Other Types of Dimensions 489 26531ch12.qxd 4/3/07 7:24 PM Page 489 10. Click the Radius button on the Dimension toolbar. 11. Click the inside arc of the balcony at a point about 30° above the right quadrant point. The radius dimension appears in dashed form, and it now has an arrow instead of a tick mark. 12. Move the cursor to the outside of the balcony, and place the dimen- sion text so that it looks similar to Figure 12.28. FIGURE 12.28: The radius dimension for the balcony When placing the radial dimension, you have control over the angle of the dimension line (by where you pick the arc) and the location of the dimension text (by where you pick the second point). Using Leader Lines You will use the Multileader command to draw an arrow to features in the draw- ing to add descriptive information. As of AutoCAD 2008, leaders are no longer part of the dimension family, and you can find them on the Multileader toolbar. Before you create a leader, you need to create a multileader style: 1. Right-click a blank area of any toolbar, and choose Multileader from the menu that appears. 2. Click the Multileader Style button at the right end of the Multileader toolbar. 3. Click the New button in the Multileader Style Manager. In the Cre- ate New Mulitleader Style dialog box that opens, enter DimPlan Leader in the New Style Name box, and then click Continue (see Figure 12.29). Chapter 12 • Dimensioning a Drawing490 26531ch12.qxd 4/3/07 7:24 PM Page 490 FIGURE 12.29: Creating a new multileader style 4. The Modify Multileader Style dialog opens (see Figure 12.30). This is where you define the leader properties. In the Leader format tab, expand the Symbol drop-down list, in the Arrowhead section, and choose Right Angle. Set Size to 1'. FIGURE 12.30: The Modify Multileader Style dialog box 5. Click the Leader Structure tab. The landing is the horizontal line at the end of the leader, just before the text. Make sure the Set Landing Distance option is checked, and then enter 10" in the text box. 6. Switch to the Content tab. Expand the Text Style drop-down list, choose Dim, and set the text height to 9". Using Other Types of Dimensions 491 26531ch12.qxd 4/3/07 7:24 PM Page 491 7. In the Leader Connection area, set both the Left Attachment and Right Attachment options to Middle of Top Line. This places the middle of the top line of the leader text even with the landing. 8. Set the Landing Gap value to 6". 9. Click the OK button. 10. In the Multileader Style Manager, the DimPlans Leaders style appears at the top of the Styles list box (see Figure 12.31). Select it, click Set Current, and then click the Close button. FIGURE 12.31: The DimPlan Leaders multileader style Adding the Leader To add the leader, follow these steps: 1. Click the Multileader button on the Multileader toolbar. 2. Start the Nearest osnap, and then pick a point between the balcony radius’s dimension text and the roofline. 3. At the Specify leader landing location: prompt, click a point above and to the right of the balcony. The Text Formatting toolbar opens, and a text prompt appears near the landing. Chapter 12 • Dimensioning a Drawing492 26531ch12.qxd 4/3/07 7:24 PM Page 492 4. Enter Cover balcony w/↵ beige stucco, and then click the OK button in the Text Formatting toolbar. TIP To reposition a leader without moving the arrow, click it, and then click the grip at the middle of the landing. Move the cursor, and then the text, landing, and one end of the leader line all will move with it. 5. Pan down so that you can see the two windows to the right of the front door. 6. Add a leader that starts at the 6' window and then extends below and to the left. Enter All windows to be double paned at the text prompt. 7. Several leader lines can extend from a single landing. Click the Add Leader button, and then at the Select a multileader: prompt, click the last leader you made. An arrowhead with a leader appears attached to the cursor. Use the Nearest osnap to select a point on the surface of the 2' window, and then press ↵. 8. Reposition the text as necessary. Your drawing should look similar to Figure 12.32. FIGURE 12.32: The cabin drawing with leaders 9. Save this drawing as Cabin12a.dwg. Using Other Types of Dimensions 493 26531ch12.qxd 4/3/07 7:24 PM Page 493 Using Aligned and Angular Dimensions To get familiar with the aligned and angular dimension types, play around with the two commands, using the rooflines to experiment. Here’s how to set up Cabin12a to work with aligned and angular dimensions: 1. Make the Roof layer current. 2. Turn off all other layers by following these steps: a. Click the Layer Properties Manager button. b. In the Layer Properties Manager dialog box, place the cursor any- where on the list of layer names, and right-click to open a menu. c. Choose Select All but Current on the menu. Then, click one of the lightbulbs for any highlighted layer in the On column. d. The lightbulbs for all selected layers turn off, indicating that those layers have been turned off. The Frozen or Thawed status of each layer is unchanged. e. Highlight the Dim1 layer, click the New Layer button, and name the new layer Dim2. By Selecting Dim1 first, Dim2 is created using the same properties including color, linetype, and status. Make Dim2 current. f. Click OK to close the dialog box and return to the drawing. Every- thing has disappeared except the rooflines. 3. Pan and zoom to get a closer view of the roof. 4. Set the Endpoint osnap to be running. Now you’re ready to dimension. Using Aligned Dimensions Aligned dimensions are linear dimensions that aren’t horizontal or vertical. You place them in the same way that you place horizontal or vertical dimensions with the Linear command. You can also use the Baseline and Continue com- mands with aligned dimensions. Use the Aligned command to dimension a hipline of the roof. Try it on your own. Follow the prompts. It works just like the Linear dimension command. Start the Aligned command by clicking the Align button on the Dimen- sion toolbar. Look ahead to Figure 12.33 to see the results you should get. Chapter 12 • Dimensioning a Drawing494 26531ch12.qxd 4/3/07 7:24 PM Page 494 Using Angular Dimensions The angular dimension is the only basic dimension type that uses angles in the dimension text instead of linear measurements. Generally, tick marks aren’t used with angular dimensions, so you need to create another child dimension style for this type of dimension. Follow the steps given earlier in this chapter in the “Set- ting Up Parent and Child Dimensioning Styles” section for setting up the Radial child style. The only change you need to make is on the Symbols And Arrows tab: replace the Architectural tick with the Right Angle arrowhead. Try making an angular dimension on your own. Turn off running osnaps. You can start the Angular command by clicking the Angular button on the Dimension toolbar. Follow the prompts, and pick two of the hiplines to dimen- sion the angle between them. Figure 12.33 illustrates angular and aligned dimensions on the roof. FIGURE 12.33: The roof with angular and aligned dimensions When you change settings for a dimension style, dimensions created when that style was current automatically update to reflect the changes. You’ll modify more dimensions in the next section. You have been introduced to the basic types of dimensions—linear, radial, leader, and angular—and some auxiliary dimensions—baseline, continue, and aligned—that are special cases of the linear type. You can also use the baseline and continuous dimensions with angular dimensions. Turn all the layers on, but leave their Frozen/Thawed states as is. Make the Dim1 layer current, and then freeze the Dim2 layer. Using Other Types of Dimensions 495 26531ch12.qxd 4/3/07 7:24 PM Page 495 Using Ordinate Dimensions Ordinate dimensions are widely used by the mechanical and civil engineering professions and related trades. They differ from the kind of dimensioning you have been doing so far in this chapter in that ordinate dimensioning specifies X and Y coordinate values for specific points in a drawing based on an absolute or relative Cartesian coordinate system, rather than on a distance between two points. This method is used to dimension centers of holes in sheet metal or machine parts and to locate surveying points on an area map. You don’t need ordinate dimensions in the cabin project, so you’ll now go through a quick exercise in setting them up to dimension the holes in a steel plate. Doing so will give you a glimpse of the tools that AutoCAD provides for this type of work. If you aren’t interested in ordinate dimensioning, move on to the next section, “Modifying Dimensions,” to modify the dimensions you’ve already created for the cabin. 1. Open a new drawing, and leave the units at the default of Decimal with a precision of four decimal places. Turn polar tracking on. 2. Set up a new text style, and set 0.125 as the height. Click Apply and then Close to make it the current text style. 3. Draw a rectangle using 0,0 as the first point and 6,–4 as the second. 4. Use Zoom to Extents, and then zoom to .5x. Turn off the UCS icon. 5. Draw a circle somewhere in the upper-left quadrant of the rectangle with a radius of 0.35 units; then, using Polar Tracking mode or Ortho mode, copy that circle once directly to the right and once directly below the original and to two other locations not aligned with any other circle so the configuration looks something like the left of Fig- ure 12.34. 6. Set the Endpoint and Center osnaps to be running, and turn on Ortho mode. What you care about with ordinate dimensioning isn’t how far the holes are from each other but how far the X and Y coordinates of the centers of the holes are from a reference point on the plate. You’ll use the upper-left corner of the plate as a reference point, or datum point, because it’s positioned at the origin of the drawing, or at the 0,0 point. 7. Click the Ordinate button on the Dimension toolbar. 8. Click the upper-left corner of the rectangular plate, and then move the cursor straight up above the point you picked. When you’re about Chapter 12 • Dimensioning a Drawing496 26531ch12.qxd 4/3/07 7:24 PM Page 496 [...]... exercises in this chapter have led you through the basics of the dimensioning process For a more in-depth discussion of dimensions, refer to Mastering AutoCAD 20 08 and AutoCAD LT 20 08 by George Omura (Wiley, 2007) The next chapter will introduce you to external references, a tool for viewing a drawing from within another drawing If You Would Like More Practice… In the first practice exercise, you’ll get a... system, a sloping line that has an up-and-to-the-left direction has a down-and-to-the-right direction if you start from the opposite end So, in laying out property lines, it’s important to move in the same direction (clockwise or counterclockwise) as you progress from one segment to the next Laying Out the Property Lines You’ll set up a new drawing and then start at the upper-right corner of the property... many of the default settings for AutoCAD as I can to give you a look at what out-of-thebox, or vanilla, AutoCAD looks like—that is, how drawings look if you use the default settings for text styles, dimension styles, units, and so forth The drawing you’ll make is similar to the one you made in Chapter 2, but you know much more now: 1 Choose File ➣ New; then, in the Create New Drawing dialog box, select... the upper-right corner of the property lines straight up to a point near the top of the screen 2 Offset this line 70' to the left This will mark the end of the driveway 3 Draw a line from the lower endpoint of this offset line down a distance of 40 '-4 " Then, using polar tracking, continue this line 11 '-4 " to the right 4 Offset the 40 '-4 " line 11 '-4 " to the right Offset the newly created line 11 '-4 " to... it’s headed in a northeasterly direction And when a line from its beginning goes 5 1 3 26531ch13.qxd 3/31/07 5 1 4 12:31 PM Page 514 Chapter 13 • Managing External References down and to the left, it’s headed in a southwesterly direction, and so on A line that is headed in a northeasterly direction with a deviation from true north of 30° and 30 minutes is shown as N30d30'E in AutoCAD notation With the... plate to finish Press the F8 key to toggle Ortho mode off if you need to jog an extension line The result should look like the right of Figure 12.34 10 Repeat this procedure for the Y ordinate dimensions Once again, ignore any circles that are in vertical alignment, but include the upper-left and lower-left corners of the plate (see the bottom of Figure 12.34) F I G U R E 1 2 3 4 : Placing the first... in the lower-left quadrant of the drawing area For the second point, enter @6,2↵ 3 Turn off the UCS icon, use Zoom to Extents, and then zoom to 5x Pan to move the new rectangle down a little (see Figure 12.43) F I G U R E 1 2 4 3 : The rectangle after panning down 5 0 7 26531ch12.qxd 4/3/07 5 0 8 7:25 PM Page 5 08 Chapter 12 • Dimensioning a Drawing You want to dimension from the upper-left corner... lot 5 0 9 26531ch12.qxd 4/3/07 5 1 0 7:25 PM Page 510 Chapter 12 • Dimensioning a Drawing Are You Experienced? Now you can… 0 create a new dimension style and child style 0 place vertical and horizontal dimensions in a drawing 0 use radial, aligned, and angular dimensions 0 create multileader lines for notes 0 modify dimension text 0 override a dimension style 0 modify a dimension style 26531ch13.qxd... direction (bearing), described as a deviation from the north or south toward the east or west, is given as an angular measurement in degrees, minutes, and seconds The angles used in a bearing can never be greater than 90°, so bearing lines must be headed in one of the four directional quadrants: northeasterly, northwesterly, southeasterly, or southwesterly If north is set to be at the top of a plot plan, south... need to suppress the left extension line of the 5 '-0 " dimension because it overlaps the wall and header lines Using Dimension Overrides You suppress the left extension line with the Properties palette, which allows you to change a setting in the dimension style for one dimension without altering the style settings Follow these steps: 1 Double-click the 5 '-0 " dimension to open the Properties palette 2 . through the basics of the dimensioning process. For a more in-depth discussion of dimensions, refer to Mastering AutoCAD 20 08 and AutoCAD LT 20 08 by George Omura (Wiley, 2007). The next chapter will. Leader Lines You will use the Multileader command to draw an arrow to features in the draw- ing to add descriptive information. As of AutoCAD 20 08, leaders are no longer part of the dimension. Dimension Style dialog box. Chapter 12 • Dimensioning a Drawing 488 26531ch12.qxd 4/3/07 7:24 PM Page 488 3. Open the Use For drop-down list, and select Radius Dimensions. Then, click the Continue