Beginning AutoCAD 2002 Episode 5 pdf

Linear dimensioning 1 Select the LINEAR DIMENSION icon from the Dimension toolbar and: prompt Specify first extension line origin or <select object> respond Endpoint icon and pick line D1 prompt Specify second extension line origin respond Endpoint icon and pick the other end of line D1 prompt Specify dimension line location or [Mtext/Text respond pick any point to the left of line D1 2 From the menu bar select Dimension-Linear and: prompt Specify first extension line origin or <select object> respond Intersection icon and pick point D2 prompt Specify second extension line origin respond Intersection icon and pick point D3 prompt Specify dimension line location or respond pick any point below object. Baseline dimensioning 1 Select the LINEAR DIMENSION icon and: prompt Specify first extension line origin respond Intersection icon and pick point P1 prompt Specify second extension line origin respond Intersection icon and pick point P2 prompt Specify dimension line location respond pick any point above the line. 2 Select the BASELINE DIMENSION icon from the Dimension toolbar and: prompt Specify a second extension line origin respond Intersection icon and pick point P3 prompt Specify a second extension line origin respond press the ESC key to end command. 3 The menu bar selection Dimension-Baseline could have been selected for step 2. Continue dimensioning 1 Select the LINEAR DIMENSION icon and: prompt Specify first extension line origin respond Intersection icon and pick point K1 prompt Specify second extension line origin respond Intersection icon and pick point K2 prompt Specify dimension line location respond pick any point to right of the line. 2 Menu bar with Dimension-Continue and: prompt Specify a second extension line origin respond Intersection icon and pick point P3 prompt Specify a second extension line origin respond press ESC. 3 The Continue-Dimension icon could have been selected for step 2. Dimensioning 113 Beginning with AutoCAD 2002.qxd 14/06/2002 19:05 Page 113 Diameter dimensioning Select the DIAMETER DIMENSION icon from the Dimension toolbar and: prompt Select arc or circle respond pick the larger circle prompt Specify dimension line location respond drag out and pick a suitable point. Radius dimensioning Select the RADIUS DIMENSION icon and: prompt Select arc or circle respond pick the arc prompt Specify dimension line location respond drag out and pick a suitable point. Angular dimensioning Select the ANGULAR DIMENSION icon and: prompt Select arc, circle, line or respond pick line B1 prompt Select second line respond pick line B2 prompt Specify dimension arc line location respond drag out and pick a point to suit. Aligned dimensioning Select the ALIGNED DIMENSION icon and: prompt Specify first extension line origin respond Endpoint icon and pick line B1 prompt Specify second extension line origin respond Endpoint icon and pick other end of line B1 prompt Specify dimension line location respond pick any point to suit. Leader dimensioning Select the LEADER DIMENSION icon and: prompt Specify first leader point respond Nearest icon and pick any point on smaller circle prompt Specify next point respond drag to a suitable point and pick prompt Specify next point respond right-click prompt Enter text width<0> respond right-click prompt Enter first line of annotation text enter R3 <R> prompt Enter next line of annotation text respond right-click to end leader dimension command. 114 Beginning AutoCAD 2002 Beginning with AutoCAD 2002.qxd 14/06/2002 19:05 Page 114 Dimension options When using the dimension commands, the user may be aware of various options when the prompts are displayed. To investigate these options: 1 Make layer OUT current and draw five horizontal lines of length 75 at the right-side of the screen then make layer DIMS current. 2 The RETURN option Select the LINEAR DIMENSION icon and: prompt Specify first extension line origin or <select object> respond press the RETURN/ENTER key prompt Select object to dimension respond pick the top line prompt Specify dimension line location respond pick above the line – fig. (a). 3 The ANGLE option Select the LINEAR DIMENSION icon, press RETURN, pick the second top line and: prompt Specify dimension line location and [Mtext/Text/Angle enter A <R> – the angle option prompt Specify angle of dimension text enter 15 <R> prompt Specify dimension line location respond pick above the line – fig. (b). 4 The ROTATED option LINEAR dimension icon, right-click, pick third line and: prompt Specify dimension line location enter R <R> – the rotated option prompt Specify angle of dimension line<0> enter 15 <R> prompt Specify dimension line location respond pick above the line – fig. (c). 5 The TEXT option LINEAR dimension icon, right-click, pick the fourth line and: prompt Specify dimension line location enter T <R> – the text option prompt Enter dimension text<75> enter THIS DIMENSION IS: 75 <R> prompt Specify dimension line location respond pick above the line – fig. (d). 6 Dimensioning with keyboard entry At the command line enter DIM <R> and: prompt Dim enter HOR <R> – horizontal dimension prompt Specify first extension line origin respond right-click and pick the fifth line prompt Specify dimension line location respond pick above the line prompt Enter dimension text<75> enter SEVENTY-FIVE <R> – fig. (e) prompt Dim and ESC to end command. Dimensioning 115 Beginning with AutoCAD 2002.qxd 14/06/2002 19:05 Page 115 Note 1 At this stage your drawing should resemble Fig. 19.2. 2 As stated earlier, the dimensions in Fig. 19.2 may differ in appearance from those which have been added to your drawing. This is because I have used the ‘default AutoCAD dimension style’ and made no attempt to alter it. The object of the exercise was to investigate the dimensioning process and dimension styles will be discussed in the next chapter. 3 The <RETURN> selection is useful if a single object is to be dimensioned. It is generally not suited to baseline or continue dimensions. 4 Object snap is used extensively when dimensioning. This is one time when a running Object Snap (e.g. Endpoint) will assist, but remember to cancel the running object snap! 5 From the menu bar select Format-Layer to display the Layer Properties Manager dialogue box. Note the layer Defpoints. We did not create this layer. It is automatically made by AutoCAD any time a dimension is added to a drawing. This layer can be turned off or frozen but cannot be deleted. It is best left untouched. Dimension terminology All dimensions used with AutoCAD objects have a terminology associated with them. It is important that the user has an understanding if this terminology especially when creating dimension styles. It is in the users interest to know the various terms used and Fig. 19.3 explains the basic terminology when dimensions are added to a drawing. 116 Beginning AutoCAD 2002 Figure 19.3 Dimension terminology. Beginning with AutoCAD 2002.qxd 14/06/2002 19:05 Page 116 1 The dimension and extension lines. These are made up of: a) dimension line b) extension line – the actual line – an origin offset from the object – the dimension text – an extension beyond the line – arrowheads – spacing (for baseline) – extension lines. 2 Centre marking. This can be: a) a mark b) a line c) nothing. 3 Dimension text. It is possible to: a) have interior dimension line drawn or not drawn b) display alternative units, i.e. [imperial] c) draw a frame around the dimension text. 4 Arrowheads. AutoCAD 2002 has several arrowheads for the dimension line and has the facility for user defined arrowheads. A selection is displayed. 5 Dimension text alignment. It is possible to align the dimension relative to the dimension line by altering certain dimension variables. A selection of dimension text positions is displayed. Summary 1 AutoCAD 2002 has automatic, associative dimensions. 2 Dimensioning can be linear, radial, angular, ordinate or leader. 3 The diameter and degree symbol are automatically added when using radial or angular dimensions. 4 Object snap modes are useful when dimensioning. 5 A layer DEFPOINTS is created when dimensioning. The user has no control over this layer. 6 Dimensions should be added to a drawing using a Dimension Style. Dimensioning 117 Beginning with AutoCAD 2002.qxd 14/06/2002 19:05 Page 117 Dimension styles 1 Dimension styles allow the user to set dimension variables to individual/company requirements. This permits various styles to be saved for different customers. To demonstrate how a dimension style is ‘set and saved’, we will create a new dimension style called A3DIM, use it with our WORKDRG drawing and then save it to our standard sheet. Note 1 The exercise which follows will display several new dialogue boxes and certain settings will be altered within these boxes. It is important for the user to become familiar with these Dimension Style dialogue boxes, as a good knowledge of their use is essential if different dimension styles have to be used. 2 The settings used in the exercise are my own, designed for our A3PAPER standard sheet. 3 You can alter the settings to your own values at this stage. Getting started Open your C:\BEGIN\WORKDRG drawing to display the component created from a previous chapter, i.e. red outline with green centre lines. Activate the Draw, Modify, Dimension and Object Snap toolbars. Setting dimension style A3DIM 1 Either a) menu bar with Dimension-Style or b) Dimension Style icon from Dimension toolbar prompt Dimension Style Manager dialogue box with a) Current Dimstyle: ISO-25 or similar b) Styles for selection c) Preview of current dimstyle d) Description of current dimstyle respond pick New prompt Create New Dimension Style dialogue box respond 1. alter New Style Name: A3DIM 2. Start with: ISO-25 or similar 3. Use for: All dimensions – Fig. 20.1 4. Pick Continue prompt New Dimension Style: A3DIM dialogue box with six tab options for selection respond continue with the tab selections which follow. Chapter 20 Figure 20.1 Create New Dimension Style dialogue box. Beginning with AutoCAD 2002.qxd 14/06/2002 19:05 Page 118 2 Lines and Arrows respond pick Lines and Arrows tab prompt Lines and Arrows tab dialogue box – probably active? alter 1. Baseline Spacing: 10 2. Extend beyond dim lines: 2.5 3. Offset from origin: 2.5 4. Arrowheads: both Closed Filled 5. Leader: Close Filled 6. Arrow size: 3.5 7. Center mark for Circle; Type: Mark; Size: 2 and dialogue box similar to Fig. 20.2. 3 Text respond pick Text tab prompt Text tab dialogue box alter 1. Text Style: Standard – this will be altered later 2. Text Color: Bylayer 3. Text height: 4 4. Vertical text placement: Above 5. Horizontal text placement: Centered 6. Offset from dim line: 1.5 7. Text Alignment: ISO Standard and dialogue box similar to Fig. 20.3. Dimension styles 1 119 Figure 20.2 Lines and Arrows tab dialogue box. Beginning with AutoCAD 2002.qxd 14/06/2002 19:05 Page 119 4 Fit respond pick Fit tab prompt Fit tab dialogue box alter 1. Fit options: Either the text or the arrows, whichever fits best active, i.e. black dot 2. Text Placement: Beside the dimension line 3. Scale for Dimension Feature: Overall scale: 1 4. Fine tuning: both not active, i.e. no black dots and dialogue box similar to Fig. 20.4. 120 Beginning AutoCAD 2002 Figure 20.3 The Text tab dialogue box. Figure 20.4 The Fit tab dialogue box. Beginning with AutoCAD 2002.qxd 14/06/2002 19:05 Page 120 5 Primary Units respond pick Primary Units tab prompt Primary Units tab dialogue box alter A. Linear Dimensions 1. Unit Format: Decimal 2. Precision: 0.00 3. Decimal separator: ‘.’ Period 4. Round off: 0 5. Scale factor: 1 6. Zero Suppression: Trailing active, i.e. tick in box B. Angle Dimensions 1. Units Format: Decimal Degrees 2. Precision: 0.00 3. Zero Suppression: Trailing active and dialogue box similar Fig. 20.5. 6 Alternate Units respond pick Alternate Units tab prompt Alternate Units tab dialogue box respond Display alternate units not active, i.e. no tick and dialogue box similar to Fig. 20.6. 7 Tolerances respond pick Tolerances tab prompt Tolerances tab dialogue box respond Tolerance Format Method: None and dialogue box similar to Fig. 20.7. Dimension styles 1 121 Figure 20.5 The Primary Units tab dialogue box. Beginning with AutoCAD 2002.qxd 14/06/2002 19:05 Page 121 122 Beginning AutoCAD 2002 Figure 20.6 The Alternate Units tab dialogue box. Figure 20.7 The Tolerances tab dialogue box. Beginning with AutoCAD 2002.qxd 14/06/2002 19:05 Page 122 [...]... next: @0,70 PQ first: 240, 150 next: @50 < 45 XY first: 155 , 150 next: @60 . to Fig. 20.4. 120 Beginning AutoCAD 2002 Figure 20.3 The Text tab dialogue box. Figure 20.4 The Fit tab dialogue box. Beginning with AutoCAD 2002. qxd 14/06 /2002 19: 05 Page 120 5 Primary Units respond. 20.7. Dimension styles 1 121 Figure 20 .5 The Primary Units tab dialogue box. Beginning with AutoCAD 2002. qxd 14/06 /2002 19: 05 Page 121 122 Beginning AutoCAD 2002 Figure 20.6 The Alternate Units. chapter. 128 Beginning AutoCAD 2002 Beginning with AutoCAD 2002. qxd 14/06 /2002 19: 05 Page 128 Modifying objects The draw and modify commands are probably the most commonly used of all the AutoCAD