The previous chapter emphasized using existing geometry (or objects) in a drawing to create new geometry. In this chapter, you’ll look at new tools for forming an efficient drawing strategy. Before getting back to the cabin, I’ll give you a brief overview of the tools available for starting and running commands.
In this chapter, you will learn to
STRETCH
commandDeveloping a drawing strategy begins with determining the best way to start a command and when to start it. The Autodesk® AutoCAD® program provides several ways to start most of the commands you’ll be using. As you have seen, you can start the OFFSET
, FILLET
, TRIM
, and EXTEND
commands either from the Ribbon’s Home tab ⇒ Modify panel or by typing the first letter or two of the command and then pressing ↵.
Remember that if you have just ended a command, you can restart that command by pressing ↵, by pressing the spacebar, or by right-clicking. When you right-click, a context menu appears near the cursor. The top item on this menu is always Repeat Command, where Command is the last command used. For example, if you’ve just finished using the ERASE
command and you right-click, the top item of the context menu is Repeat Erase. If you’ve used a command recently, you can select that command by pausing the cursor (hovering) over the Recent Input option and then selecting that command from the cascading menu that appears (see Figure 5-1).
In this chapter, I’ll introduce you to several new commands and, through the step-by-step instructions, show you some alternative methods for accomplishing tasks similar to those you have already completed. You’ll add front and back decks and steps, thresholds, and kitchen and bath fixtures to the cabin floor plan (see Figure 5-2). For each of these tasks, the focus will be on making your job easier by using objects and geometry that are already in the drawing and on choosing the appropriate tools to accomplish tasks more quickly and efficiently.
To get started, let’s take a look at the two thresholds. Each threshold is represented with three simple lines. You could manually draw these lines with the skills you’ve learned so far, but we want to find the most efficient way. The trick will be to see which part of the drawing you can effectively use to generate and position those lines. As illustrated in Figure 5-3, the thresholds extend 2″ (51 mm) beyond the outside wall line and run 3″ (76 mm) past either jamb line.
Thresholds generally are used on doorway openings when the level changes from one side of the opening to the other or to prevent rain and dust from entering the structure. This usually occurs at entrances that open from or to the outside. Although they are quite different in shape, each threshold for the cabin has the same geometry as the steps. The lip of each threshold is offset 2″ (51 mm) from the outside wall, and each edge runs 3″ (76 mm) past the doorjamb (see Figure 5-3). You’ll use a temporary tracking point with Polar Tracking and direct entry to draw the three thresholds for the cabin.
As you can see in Figure 5-3, the front threshold is 7′-6″ (2286 mm) wide, extending 3″ (76 mm) past the doorway on each side. You can draw a line from the endpoint of one of the jamb lines down 3″ (76 mm) and then draw the perimeter of the threshold. Here’s how you do it:
I04A-FPLAYO.dwg
(M04A-FPLAYO.dwg
) and use the ZOOM
command options to achieve a view similar to Figure 5-4. The file is also available from this book’s web page at www.sybex.com/go/autocad2016ner or www.thecadgeek.com.
LINE
command.
You need to start the threshold 3″ (76 mm) below the bottom jamb and in line with the outside wall line. Unfortunately, there is no feature to snap the cursor to at that point. The techniques that you’ve previously used would require offsetting the jamb line or starting the line at the jamb and drawing an overlapping line 3″ (76 mm) downward. Both of these methods would require you to erase the unnecessary line after the threshold is complete.
Instead of wasting time drawing and then erasing lots of unnecessary line work, you will begin using the Object Snap Tracking tool. This tool will help eliminate the need to create unnecessary geometry. Using the Object Snap Tracking tool requires you to specify a location in the drawing area, called a temporary tracking point, relative to existing features or other locations.
The green cross indicates the temporary tracking point for the Object Snap Tracking tool, and the X indicates the point where the line will start.
3
↵ (76
↵) to use the direct entry method to start the first line 3″ (76 mm) below the temporary tracking point. With Ortho mode turned on, the point selected is directly below the corner of the jamb.2
↵ (51
↵), as shown in Figure 5-6.
AutoCAD draws the bottom edge of the threshold. You used direct entry with Ortho mode again, and you didn’t have to enter the relative polar or the Cartesian coordinates.
7
′6
″↵ (2286
↵). AutoCAD draws the front edge of the threshold.PER
at the command line to enable the Perpendicular osnap.LINE
command.
The completed front threshold looks like Figure 5-8.
ZOOM
) command to view the completed front threshold with the whole floor plan. Remember, by default, double-clicking the middle button on a wheel mouse performs a Zoom Extents (ZOOM
) command.I05-01-FrontThreshold.dwg
(M05-01-FrontThreshold.dwg
) by choosing Application menu ⇒ Save As ⇒ AutoCAD Drawing.The method of drawing the threshold for the back door is the same as the method used to draw the front threshold. You will use Ortho mode, direct input, and Object Snap Tracking to draw the lines. Here is how it’s done:
I05-01-FrontThreshold.dwg
(M05-01-FrontThreshold.dwg
) is open.LINE
command and place the cursor over the left corner of the lower jamb. Then, after the temporary tracking point cross appears inside the endpoint marker, move the cursor directly downward, as shown in Figure 5-9.
3
↵ (76
↵) to set the start point of the line 3″ (76 mm) below the edge of the jamb.2
↵ (51
↵) to draw the lower edge of the threshold.3
′6
″↵ (1067
↵).LINE
command. The back threshold should look like Figure 5-10.
ZOOM
) command to view the completed front and back thresholds with the whole floor plan.I05-02-BackThreshold.dwg
(M05-02-BackThreshold.dwg
).When you drew the first threshold, this exercise may have seemed complicated, but it was probably easier when you drew the second one. Like many techniques available in AutoCAD, these methods will become second nature with a little practice, and you’ll use them more efficiently. In the next exercise, you will draw the cabin’s front deck and stairs, and then you’ll use the existing geometry to draw the back deck and stairs.
The decks consist of the platform, posts, railings, and a set of stairs. You’ll begin by using the OFFSET
command to draw polylines for the perimeter to facilitate the drawing of the railing lines. Then you’ll continue the construction by using lines and the OFFSET
and TRIM
commands. You will also begin using the Temporary Track Point osnap, an option with the Object Snap Tracking tool.
The dimensions of the front deck that you’ll draw are shown in Figure 5-11.
Follow these steps to draw the front deck:
I05-02-BackThreshold.dwg
(M05-02-BackThreshold.dwg
) is open.This has the same effect as clicking the Polar Tracking button in the status bar or pressing F10 from the Application window.
The Polar Tracking button is turned on in the status bar, and Ortho mode is automatically turned off. Polar Tracking is similar to Ortho mode, but it provides more angular increments to which you can snap the cursor.
PLINE
) command, and draw a polyline from the lower-right corner of the cabin to a point 8′-0″ (2438 mm) to the right.PER
↵ at the command line or by pressing the Ctrl key and the right mouse button simultaneously. Place the cursor over the top-outside horizontal line of the cabin, and when the Snap marker appears (see Figure 5-13), click to draw the vertical line of the deck’s perimeter.
PLINE
) command.
Your drawing should look like Figure 5-14.
OFFSET
command.I05-03-FrontDeck.dwg
(M05-03-FrontDeck.dwg
).There are four posts on the deck: two 8″ (204 mm) posts at the corners that hold up the roof and two 4″ (102 mm) posts at the top of the stairs. You will use the Rectangle (RECTANG
) command to draw the posts and the MIRROR
command to copy them.
I05-03-FrontDeck.dwg
(M05-03-FrontDeck.dwg
) is open.RECTANG
) command, found on the Home tab ⇒ Draw panel ⇒ Rectangle tool, to draw a post 8″ × 8″ at the lower-right corner of the deck.
To do this, start the Rectangle (RECTANG
) command. At the Specify first corner point or:
prompt, click the endpoints where the lines form the lower-right corner of the deck. At the Specify other corner point or:
prompt, enter -8,8
↵ (-204,204
↵) to draw the first 8″ (204 mm) post.
The rectangle should be similar to Figure 5-15.
MIRROR
command (Home tab ⇒ Modify panel ⇒ Mirror tool).Specify first point of mirror line:
prompt, use the Midpoint Object Snap. Then pause the cursor over either of the vertical handrail lines.
When a feature is symmetrical like the deck, you can use the Midpoint snap to mirror objects around the centerline.
No
option for deleting the source object.TRIM
command to trim the short polyline segments that fall within the posts.
When you are finished, each segment should look similar to Figure 5-17.
I05-04-DeckPosts.dwg
(M05-04-DeckPosts.dwg
).The 4″ (102 mm) posts at the top of the stairs are centered on the 3″ (72 mm) handrails on the deck and on the stairs. To create the lower small post, you need to locate the bottom-right corner at a point 1/2″ (15 mm) to the right of the front handrail and 5′-8 1/2″ (1740 mm) from the bottom-right corner of the deck. Follow these steps:
I05-04-DeckPosts.dwg
(M05-04-DeckPosts.dwg
) is open.COPY
command from the Home tab ⇒ Modify panel on the Ribbon.Specify second point or:
prompt, enter .5,5
′8.5
″ (15,1740
).COPY
command. The copied post appears as shown in Figure 5-18.
SCALE
command by clicking the Scale button from the Home tab ⇒ Modify panel; then select the new rectangle.SCALE
command active, select the lower-right corner as the base point. Then move the cursor to see the effect when the scale is based from that corner. A copy of the selected object appears, as shown in Figure 5-19.0.5
↵ to scale the rectangle to 50 percent of its current size.
I05-05-StairPosts.dwg
(M05-05-StairPosts.dwg
).You could mirror the 4″ (102 mm) rectangle now to create the reciprocal post, but we’ll wait until the stair handrails are complete and then mirror both objects at once. The first stair handrail is 3″ (76 mm) wide and centered on the 4″ (102 mm) post, so you’ll use a temporary tracking point to locate the first point of the line.
I05-05-StairPosts.dwg
(M05-05-StairPosts.dwg
) is open.LINE
command, and enter TT
↵ at the command line to establish a temporary track point..5
↵ (13
↵) to place the start point 1/2″ (13 mm) above the corner.3
′5.5
↵ (1054
↵).3
↵ (72
↵).3
′5.5
↵ (1054
↵).
Your first handrail should look like Figure 5-20.
I05-06-DrawStairRail.dwg
(M05-06-DrawStairRail.dwg
).You can now mirror the post and railing to draw them on the opposite side of the stairway. You can’t use the midpoint of the deck’s perimeter line as one point of the mirror line because the stair is centered on the front door and not on the deck. You can, however, use the midpoint of the front door’s threshold. Follow these steps:
I05-06-DrawStairRail.dwg
(M05-06-DrawStairRail.dwg
) is open.MIRROR
command.Your deck should look like Figure 5-22.
EXPLODE
command.COPY
command from the Home tab ⇒ Modify panel. Select the outside perimeter line of the deck to begin building the stairs.Specify base point:
prompt.
COPY
command by entering A
↵ at the Specify second point:
prompt.5
↵ at the Enter number of items to array:
prompt.10
↵ (254
↵) at the Specify second point or:
prompt (see Figure 5-23).
COPY
command ends, and your stairs are drawn.
Now you will use the TRIM
command to trim away the stair lines that extend into and beyond the railings and the lines that pass through the 4″ (102 mm) posts.
TRIM
command. Select both of the inside lines of the stairway handrails and the 4″ (102 mm) post polylines as the cutting-edge objects.
When complete, your front stairway should look like Figure 5-25.
I05-07-FrontStairs.dwg
(M05-07-FrontStairs.dwg
).The deck, handrails, posts, and stairs at the rear portion of the cabin are similar to the same features at the front of the cabin. One of the most significant strengths of CAD software over traditional hand drafting is the ability to use existing geometry and linework in a drawing to create additional identical or similar objects. In this section, you will first mirror the front deck to the back of the cabin. I will then introduce you to the STRETCH
command to adjust the lines to match the cabin’s structure. Figure 5-26 shows the dimensions of the rear deck that are different from those on the front deck.
Several similarities exist between the front and back decks of the cabin. Using these similarities to your advantage, the following steps utilize this existing geometry by mirroring the front deck to the back of the cabin:
I05-07-FrontStairs.dwg
(M05-07-FrontStairs.dwg
) is open.MIRROR
command.If you inadvertently select an unwanted object, hold down the Shift key and pick the object again to deselect it. The dashed, selected set should look like Figure 5-27.
Specify first point of mirror line:
prompt, activate the Midpoint osnap and click near the midpoint of the top, outside wall line.
As discussed earlier, as long as the Midpoint snap marker displays at the correct midpoint, it is not necessary to pick the exact midpoint of the line.
I05-08-MirrorDeck.dwg
(M05-08-MirrorDeck.dwg
).The STRETCH
command is used to lengthen or shorten objects in the drawing area. The major restriction when using it is that the objects must be selected with a crossing window or crossing polygon, so be sure to define your selection window from right to left or to enter CR
↵ at the Select objects:
prompt.
When part of an object resides inside the crossing window borders, the portion inside the window is moved, the portion crossing the border is stretched, and the portion outside the border is unaffected. When an object is completely inside the crossing window, it is affected as if the MOVE
command were used.
Figure 5-29 shows the result when the top portion of the objects in a drawing are selected and stretched. The far-left image shows a crossing selection window encompassing the entire top portion of the objects, and the middle-left image shows the result of stretching the objects upward. The middle-right image shows a crossing selection window encompassing only the right half of the top portion of the objects, and the far-right image shows the result of stretching the objects upward. Some objects cannot be stretched, such as circles, ellipses, and blocks.
Complete the following steps to fix the rear deck and stairs by using the STRETCH
command:
I05-08-MirrorDeck.dwg
(M05-08-MirrorDeck.dwg
) is open.STRETCH
command from the Home tab ⇒ Modify panel ⇒ Stretch tool, or enter S
↵ at the command line.Select objects:
prompt, place the cursor above the deck and to the right of the stairs, but be sure the point is to the left of the threshold (see Figure 5-30).Specify opposite corner:
prompt, click a point outside and to the left of the deck, as shown in Figure 5-30. The deck objects glow to indicate that they are selected. Press ↵ to discontinue selecting objects.
Like the MOVE
command, STRETCH
requires you to specify a base point and a second point to define the result of the stretch. The selected objects are stretched to the same distance and angle as the relationship between those two points. For example, after selecting objects to stretch on the right side of the drawing area, you can select a base point on the left side of the drawing area and a second point 2″ above the base point. The selected objects on the left are stretched upward 2″.
You can reference objects or features in the drawing area or select a random point for the base and specify the angle and distance for the second point.
4
′↵(1220
↵). The deck is stretched 4′-0″ (1220 mm) to the right.I05-09-StretchDeck.dwg
(M05-09-StretchDeck.dwg
).To complete the back deck, you need to align the center of the stair with the center of the door. To do this, we’ll combine what you already know about object snaps with the STRETCH
command and a feature named point filters. Point filters, also called coordinate filters, are tools that allow you to use only the X, Y, or Z value of a selected point in the drawing area.
For example, suppose you want to stretch an object to the center of a rectangle but you don’t know where that center is located. You could draw a bunch of construction lines, only to erase them in a few minutes, or you could forgo all of that with point filters. In this scenario, you would use the X point filter and pick the midpoint of a horizontal line from the rectangle; then you’d use the Y point filter and pick the midpoint of a vertical line from the rectangle.
The resulting location is at the intersection of the midpoints of the two sides of the rectangle at the center point. More important is that you didn’t spend any unnecessary time drawing and then erasing construction lines. Let’s take a look at how you can employ this same method to finish the back deck. Follow these steps:
I05-09-StretchDeck.dwg
(M05-09-StretchDeck.dwg
) is open.Specify base point or:
prompt, use the Midpoint osnap and pick the midpoint of the top step.
Specify second point or:
prompt, hold the Shift key down and right-click to open the Osnap context menu. Choose Point Filters ⇒ .X (see Figure 5-34).
This allows you to pick a point that is horizontally (X) equal to the same location as the point you selected in step 4 and vertically (Y) equal to the midpoint of the threshold.
The prompt in the command-line interface has .X appended to indicate that AutoCAD will use only the X component of the next location picked.
Move the cursor around in the drawing area, and you’ll see that the movement of the stairs is now restricted to the y-axis. In the command-line interface, the notation (need YZ)
is appended to the prompt, indicating that AutoCAD will use only the Y and Z components of the next location picked. (Only the y-axis is referenced if you are using the Autodesk® AutoCAD LT® program.)
I05-10-PointFilter.dwg
(M05-10-PointFilter.dwg
).The kitchen for the cabin will have a stove, a refrigerator, and a counter with a sink. The refrigerator is set 2″ (51 mm) away from the back wall. Approaching this drawing task, your goal is to think about the easiest and fastest way to complete it. The first step in deciding on an efficient approach is to ascertain what information you have about the various parts and what existing elements in the drawing will be available to assist you. Figure 5-37 gives you the basic dimensions, and you’ll get more detailed information about the sink and stove as you progress through the exercise.
Although the counter is in two pieces, you’ll draw it as one piece and then cut out a section for the stove. You can try two different ways to draw the counter to see which method is more efficient.
The first drawing method uses Object Snap Tracking and direct entry:
I05-10-PointFilter.dwg
(M05-10-PointFilter.dwg
) from the book’s web page.LINE
command to begin drawing the counter.8
↵ (204
↵) to start the counter line 8″ (204 mm) from the corner of the jamb (see Figure 5-39).2
′↵ (610
↵).4
′↵ (1220
↵).
At this point, you have drawn two line segments defining the counter on the back wall of the cabin. You can see the dimensions in Figure 5-37, shown earlier.
5
′1
″↵ (1550
↵) to draw the long counter line that runs in front of the sink.
LINE
command.As with launching commands, most tasks in AutoCAD give you options galore for completing them. Although some methods are considered more efficient than others, the “best” method is often a matter of personal preference. In this exercise, you’re going to draw the same counter you drew in the previous exercise, this time using the OFFSET
and FILLET
commands.
To complete this exercise, you’ll need to erase the countertop you just drew. You could use the ERASE
command to do this, but because all four of the line segments were drawn in one cycle of the LINE
command, you can also use the UNDO
command. Follow these steps to begin using the OFFSET
and FILLET
commands:
U
↵ at the command line, or use the standard Windows keyboard shortcut Ctrl+Z.
Alternatively, you can open I05-10-PointFilter.dwg
(M05-10-PointFilter.dwg
) from the book’s web page.
The counter you just drew should disappear. If you ended the LINE
command while drawing the counter and had to restart it before you finished, you might have to click the Undo button more than once.
If you undo too much, click the Redo button, which is just to the right of Undo.
Now you’ll draw the counter again, this time using the OFFSET
and FILLET
commands.
OFFSET
command. This time, offset the inside left wall line 7′-1″ (2159 mm) to the right.FILLET
command with a radius of 0 to clean up the three corners. Be sure to click the portions of the lines that you want to retain.
I05-11-KitchenCounter.dwg
(M05-11-KitchenCounter.dwg
).Now that you have tried both methods of creating the counter, you can decide which one is more practical for you. Both are powerful techniques for laying out orthogonal patterns of lines for walls, counters, and other objects.
The stove and refrigerator are simple rectangles. Here you will use the Temporary Tracking Point osnap to locate the first corner of each shape:
I05-11-KitchenCounter.dwg
(M05-11-KitchenCounter.dwg
) is open.REC
↵ at the command line.2
↵ (51
↵), as shown in Figure 5-42.
This starts the rectangle 2″ (51 mm) from the back wall, along the side of the counter.
36,-36
↵914,-914
↵.
The Rectangle (RECTANG
) command ends, and the refrigerator is drawn at the end of the counter that is running along the back wall. Next you’ll use a similar process to draw a basic outline of the stove.
1
′5
″↵ or 17
↵ (432
↵). Then enter 26,27
↵ (660,686
↵) to complete the rectangle.TRIM
command to trim away the front edge of the counter that passes through the stove.
Your kitchen should look like Figure 5-43.
I05-12-Refrigerator.dwg
(M05-12-Refrigerator.dwg
).At this point, the cabin is really starting to take shape with the numerous lines, arcs, and polylines that you have drawn. There is, however, a significant disconnect between what you see and what AutoCAD sees while viewing the cabin. To you, it’s a cabin; you see how the stairs are spaced equally, how the wall intersections form perpendicular angles, and in general how objects relate to other objects within your drawing.
AutoCAD, on the other hand, sees nothing more than a collection of lines, arcs, and polylines. It doesn’t know that walls should form 90° angles where they intersect or that the two lines representing door openings should be parallel and spaced a certain distance apart. Currently, every object inside your drawing is independent from the other objects in your drawing.
Parametric drawing offers a solution to this disconnect; it allows you to assign both geometric and dimensional constraints to the objects inside your drawing. Whereas dimensional constraints must be applied manually, geometric constraints may be applied manually, automatically, or inferred while drawing. Using the dimensions shown in Figure 5-44, you’ll have the chance to explore each of these methods as you use parametrics to complete the stove.
The first step in using parametric drawing is to define how objects should interact geometrically. This is done by assigning geometric constraints to your model. These constraints will reinforce the use of tools such as object snaps to define the intersection of two lines as coincident, or two lines forming a right angle as perpendicular. Because you’re not yet dealing with size, the primary focus in this exercise is to ensure that objects that should intersect do so, objects that should form right angles are indeed perpendicular, and parallel lines are truly parallel.
Assuming you were diligent in creating your linework, the AutoConstrain tool will automatically determine and assign the necessary geometric constraints. Follow these steps to autoconstrain your stove:
I05-12-Refrigerator.dwg
(M05-12-Refrigerator.dwg
) is open, and zoom in to a closer view of the stove.After you invoke AutoConstrain, a series of icons appear along the perimeter of the stove, as shown in Figure 5-45. These icons illustrate the geometric relationships AutoCAD has established between the four lines that define the outline of your stove.
The positioning of these icons may be slightly different from what’s shown in Figure 5-45, but you should have the same geometric constraints as shown.
The geometric relationship is displayed as you hover over each Geometric Constraint icon. For instance, the parallel geometric constraint highlights both the adjacent Geometric Constraint icon and the line to which the two lines are parallel. This inquiry method is an especially helpful way of visualizing which objects relate to other objects inside your drawing.
LINE
command and the Nearest and Perpendicular object snaps to draw a vertical line, as shown in Figure 5-46.
I05-13-AutoConstrain.dwg
(M05-13-AutoConstrain.dwg
).
Don’t worry about being accurate as you draw the stove at this point. You’ll apply dimensional constraints in a moment. Right now you’re interested in only the geometric relationships between objects.
The next step is to draw the circles that represent the burners. As with the previous exercise, you don’t have to be overly concerned about size at this point. Instead, focus on getting the geometry correct first, and then you’ll come back to further constrain the stove with dimensional constraints.
I05-13-AutoConstrain.dwg
(M05-13-AutoConstrain.dwg
) is open.You have six options for constructing a circle:
Notice that each circle construction method has a unique icon on the left side of the flyout menu. Whichever method was used last becomes the default method when you click the Circle button, and its icon appears on the button.
Specify center point for circle or:
to Base point:
. Draw four circles as shown in Figure 5-48.
I05-14-StoveBurners.dwg
(M05-14-StoveBurners.dwg
).
Once again, your intent at this point is to develop a solid geometric representation of the stove. Before you apply dimensional constraints, I’ll show you how to add some geometric constraints.
You’ve seen how the AutoConstrain and Infer Constraints features make it easy to add geometric constraints to your drawing. Although both are incredibly powerful features, sometimes you need an extra degree of control over how geometric constraints are added. For this reason, you have the option of manually adding geometric constraints to objects inside your drawing.
Even if you had been more deliberate in drawing the burners with the proper alignment and size, the AutoConstrain feature would still have a difficult time establishing how the four burners truly interact with one another. Consequently, to ensure that the constraints are correctly applied, the best approach in this case is to define the necessary geometric constraints manually. To do so, you’ll use many of the individual constraint icons on the Parametric tab ⇒ Geometric panel.
I05-14-StoveBurners.dwg
(M05-14-StoveBurners.dwg
) is open.Select an object or [2Points]:
prompt, press the down arrow to select 2Points
, as shown in Figure 5-49.
Select second point:
prompt, use the same method to select the center point of the top-right burner, as shown on the right in Figure 5-50.
The two right burners (as if you were working at the stove and facing the rear deck) are now constrained horizontally; this means that although the two burners may be located anywhere along the y-axis, they will always be aligned along the x-axis. You can try this by using the MOVE
command to move either one of the burners. Notice how the second burner also moves even though it was not selected.
All of the burners are now constrained horizontally; however, there is no relationship between the left and right burners. To fix this, you will continue constraining the burners, this time applying Vertical constraints between the right and left burners.
Select an object or [2Points]:
prompt, click the down arrow to select 2Points
using Dynamic Input.Each of the burners is now fully constrained horizontally and vertically. Notice how moving a single burner also moves the two adjacent burners. Also note the Constraint icons under each of the burners. Your stove should look like Figure 5-51.
Because three of the burners will be the same size, you can use the Equal geometric constraint to build a relationship between the two right burners and the back-left burner. It’s important to remember that the focus here is to get the geometry correct. In the next exercise, you’ll apply dimensional constraints to size each of the burners correctly.
Your stove should look like Figure 5-52.
I05-15-GeometricConstraints.dwg
(M05-15-GeometricConstraints.dwg
).The previous several exercises gave you the opportunity to focus on geometry, not dimensions. Although the stove is geometrically correct, it’s drawn with a series of arbitrary dimensions. Dimensional constraints let you assign real values to the geometry in your drawing. Thanks to the geometric constraints you already applied to the stove, you’ll need to apply dimensional constraints to only a few key points. The geometric constraints will handle the rest for you automatically, ensuring that the integrity of the relationships is retained.
Dimensional constraints function similarly to regular dimensions in AutoCAD. You’ll take a closer look at dimensions in Chapter 12, “Dimensioning a Drawing,” but your experience with parametrics will certainly provide a great foundation from which to build. One core difference between regular dimensions and parametric dimensions is that parametric dimensions require you to select both an object and a point. In contrast, regular dimensions require you to specify only a point. You’ll use the dimensions shown earlier, in Figure 5-44, to apply the necessary dimensional constraints.
I05-15-GeometricConstraints.dwg
(M05-15-GeometricConstraints.dwg
) is open.Figure 5-54 shows the result. You have created a total of five Linear constraints. These constraints have correctly positioned the rear control panel and each of the four burners for the stove. The only thing left to do is correctly size each of the four burners.
Because you used the Equal geometric constraint on three of the burners, properly sizing the burners will require only two Radius constraints.
Select arc or circle:
prompt, select the front-right burner and choose a position for the dimensional constraint.3 1/2
″ (89 mm
) for the rad1 constraint.
The Equal geometric constraint updates the radius of the back-right and back-left burners to match the 3 1/2″ (89 mm) radius you specified for the front-right burner.
rad1+1
↵ (rad1+25
).
Figure 5-55 shows the result.
Much like formulas can reference the values of other cells in Microsoft Excel, dimensional constraints can reference other dimensional constraints. In this example, you referenced a constraint applied to the front-right burner by entering its name (rad1). The expression rad1+1 is actually a mathematical expression telling AutoCAD to gather the value of rad1 (3 1/2″) and add 1″ to it for a total radius of 4 1/2″ (114 mm).
I05-16-CompleteStove.dwg
(M05-16-CompleteStove.dwg
).In this section, you’ll draw a double sink with one basin larger than the other (see Figure 5-56). You’ll use OFFSET
, FILLET
, and TRIM
to create the sink from the counter and wall lines.
I05-16-CompleteStove.dwg
(M05-16-CompleteStove.dwg
) is open. Zoom in to the sink area, keeping the edges of the refrigerator and stove in view.OFFSET
command:
OFFSET
command, and offset the top edge of the sink downward 1′-8″ (508 mm).This forms the top and bottom edges of the sink. Next, you will draw the left and right edges of the sink.
SELECTIONCYCLING
↵ at the command line and then entering 2
↵.
Selection Cycling is a useful tool that helps you select the right object in crowded areas of a drawing.
OFFSET
command, and set the offset distance to 16″ (406 mm).
You’re going to offset the right side of the counter 1′-4″ (406 mm) to the left, but it coincides with the left side of the refrigerator. You’ll use Selection Cycling to ensure that you select the correct line.
Select object to offset:
prompt, select the right edge of the counter. Because you enabled Selection Cycling in step 3 and both the right edge of the counter and left edge of the refrigerator coincide with one another, the Selection dialog box is displayed (see Figure 5-57).
OFFSET
command by picking a point to the left of the selected line. Notice how the object highlighted in the Selection dialog box is also highlighted (with dashes) inside the drawing (see Figure 5-57).FILLET
command so that you won’t need to restart the command continually.I05-17-KitchenSink.dwg
(M05-17-KitchenSink.dwg
).This completes the kitchen area. You drew no new lines to complete this task because you created most of them by offsetting existing lines and then trimming or filleting them. Keep this in mind as you move on to the bathroom.
The bathroom has three fixtures—a sink, a shower, and a toilet—as well as a mirror and a shelving unit. While you are drawing the bathroom, you’ll draw the hot tub in the main room as well (see Figure 5-59). When drawing these fixtures, you’ll use a few object snaps over and over again. You can set one or more of the osnap choices to run continually until you turn them off. That way, you won’t have to select them each time.
You’ll set three osnaps to run continually for now, until you get used to how they work:
I05-17-KitchenSink.dwg
(M05-17-KitchenSink.dwg
) is open.By default, the Object Snap tab is automatically displayed (see Figure 5-60).
Each of the 13 osnap options has a check box and a symbol next to it. The symbol appears as a marker in the drawing when you select a particular osnap and the cursor is near a point where you can use that osnap. You can select any number of osnaps to be running simultaneously.
The Endpoint, Midpoint, and Intersection osnaps will now be active any time you’re prompted to select a point on the drawing. You can deactivate them by turning off the Object Snap button in the status bar or by pressing F3.
Now you’re ready to begin drawing the bathroom. The shower determines the placement of the other two items, so let’s start there.
You’ll start the shower unit with a rectangle and then trim away one corner. As you start this exercise, check the status bar. The Polar Tracking, Object Snap, and Object Snap Tracking buttons should be in their On positions. The rest of the buttons should be off. Follow these steps:
I05-17-KitchenSink.dwg
(M05-17-KitchenSink.dwg
) is open.Z
↵E
↵ or click the Zoom Extents button to zoom to the drawing’s extents. Then use the zoom window or the scroll wheel to view the bathroom close-up.RECTANG
) command and use the following settings:
-40,40
↵ (-1016,1016
↵).CHAMFER
command from the Home tab ⇒ Modify panel. If the Chamfer tool isn’t visible on the Ribbon, click the down arrow next to the Fillet tool, as shown in Figure 5-61.
Select first line or [Undo/Polyline/Distance/Angle/Trim/mEthod/Multiple]:
prompt, enter D
↵, or select Distance
to set a chamfer distance.1
′-8
″ (508 mm
) for the first and second chamfer distances.As you hover over the second line, a preview of the resulting chamfer is displayed, similar to the display for the FILLET
command. This allows you to confirm the chamfer distance values before completing the command.
I05-18-Shower.dwg
(M05-18-Shower.dwg
).Next, you’ll draw the sink to the right of the shower.
You’ll offset a line and draw an ellipse for this fixture while you practice using the Temporary Tracking Point osnap option in the process. The Endpoint and Midpoint osnaps are still running.
I05-18-Shower.dwg
(M05-18-Shower.dwg
) is open, and zoom in to the sink area with a zoom window.Your sink area should look like Figure 5-64.
FILLET
command to clean up the lines to form the sink counter and mirror. You will have to zoom in to each end of the mirror to select the correct end of the mirror’s sides and fillet the lines properly. Figure 5-65 shows the partially completed sink and mirror.EL
↵C
↵ to start the command from the command line.Instead of using the direct entry method to define a point with the Object Snap Tracking tool, you just used two different object snaps to define one point.
ELLIPSE
command requires you to specify a distance for each of the major and minor axes:
The ellipse is constructed, and the sink fixture is nearly complete.
Leave the view on your screen as it is for a moment.
I05-19-BathroomSink.dwg
(M05-19-BathroomSink.dwg
).
The toilet and the shelves are the final fixtures necessary in the bathroom. You’ll use the ELLIPSE
command again, along with the RECTANG
command, to draw them. You’ll also learn about a couple of new display options.
The shelves are a simple rectangle measuring 3′ × 1′ (914 mm × 305 mm). The toilet consists of a rectangle and an ellipse centered between the sink and the wall. The tank is offset 1″ (25 mm) from the back wall, and it is 9″ × 20″ (229 mm × 508 mm). The ellipse representing the seat measures 18″ (457 mm) in one direction and 12″ (304 mm) in the other. Follow these steps to add the shelves and toilet to the bathroom:
I05-19-BathroomSink.dwg
(M05-19-BathroomSink.dwg
) is open.Z
↵↵ at the command line to execute the Zoom Realtime operation. Back in the drawing, the cursor changes to a magnifying glass with plus and minus signs.Position the cursor in such a way that you have a good view of the toilet area and then release the mouse button. Right-click again and choose Exit from the context menu to end Zoom Realtime.
These zooming options are convenient tools for adjusting the view of your drawing. Let’s move to the toilet first. You need to find a way to position the toilet accurately, centering it between the wall and shower. The midpoint of the left wall line isn’t useful because the wall line runs behind the shower. You’ll have to use a reference point to locate the starting point for the toilet tank. The lower-left corner of the tank is 5″ (127 mm) from the bottom wall and 1″ (25 mm) from the left wall. Because there is no osnap feature to define the location on the left wall, you will use the From osnap to locate the corner. Follow these steps:
I05-19-BathroomSink.dwg
(M05-19-BathroomSink.dwg
) is open.RECTANG
) command, and choose the From option on the right-click Object Snap menu.
At the Base point:
prompt, click the lower-left inside corner of the bathroom.
@1,5
↵ (@25,127
↵) to place the first corner of the rectangle and then 9,20
↵ (229,508
↵).
The 9″ × 20″ (229 mm × 508 mm) toilet tank is drawn centered on the left wall (see the left of Figure 5-68).
ELLIPSE
command. If you start it from the Ribbon, be sure to select the Axis, End Ellipse tool from the Home tab ⇒ Draw panel. The command line displays a default prompt of Specify axis endpoint of ellipse or:
.
Using the Specify Axis Endpoint option and the running Midpoint osnap, you can easily define the ellipse’s location and first axis from one end of the ellipse to the other.
1
′6
↵ (457
↵). This sets the first axis.
Now, as you move the crosshair cursor, you’ll see that a line starts at the center of the ellipse, and the cursor’s movement controls the size of the other axis.
To designate the second axis, you need to enter the distance from the center of the axis to the end of it, or half the overall length of the axis.
6
↵ (152
↵).
The ellipse is complete, so you’ve finished the toilet (see the right side of Figure 5-68).
Figure 5-59 earlier in the chapter shows the proper orientation. Zoom out, and your completed bathroom should look like Figure 5-69.
I05-20-BathroomToilet.dwg
(M05-20-BathroomToilet.dwg
).
What is a cabin without a hot tub in which to relax? You’ll complete the cabin fixtures by using a polyline to draw the outside perimeter of the hot tub, offsetting this polyline to the inside, and then filleting the appropriate corners. Here’s how it’s done:
I05-20-BathroomToilet.dwg
(M05-20-BathroomToilet.dwg
) is open, and verify that the Polar Tracking button is still turned on in the status bar.PLINE
) command, and click the bottom-left inside corner of the pop-out to the right of the bathroom, as shown in Figure 5-70.4
′5-5/8
″↵ (1362
↵) to draw the first vertical line. Refer to Figure 5-59 for the dimensions of the hot tub.
Earlier in this chapter, you set the Polar Tracking Increment Angle value to 45.00 in the Drafting Settings dialog box. This setting lets you easily place the cursor at 45° increments from a set point rather than at the 90° increments provided by using Ortho mode.
3
′6-7/8
″↵ (1089
↵) to draw the diagonal line (see Figure 5-71).
Close
or enter C
↵ at the command line to close the polyline and end the Polyline (PLINE
) command.OFFSET
command to offset the polyline 4″ (102 mm) to the inside.FILLET
command, and set the Radius value to 3
″ (76
).FILLET
command, but this time choose the Polyline option.I05A-FPLAYO.dwg
(M05A-FPLAYO.dwg
).
The following exercises will give you the opportunity to practice the skills and techniques you have learned.
As is true for almost any skill, the key to mastery is practice. Redrawing the entire cabin might seem daunting at this point, when you think of how long it took you to get here. But if you try it all again, starting from Chapter 3, “Setting Up a Drawing,” you’ll find that it will take about half the time that it did the first time. If you do it a third time, it’ll take half that time again. Once you understand the techniques and how the commands work, feel free to experiment with alternative techniques to accomplish tasks and with other options for the commands.
If you have a specific project in mind that you would like to draw in AutoCAD, so much the better. Try drawing the floor plan of your home or a classroom.
Once you put some furniture in the cabin, you’ll quickly see how small it is! But it can still accept some basic furniture without seeming too cramped. You should be able to add the following:
Use a tape measure and go around your office or home to determine the approximate dimensions of each piece of furniture. The goal here is not so much to ensure accuracy of scale but to practice drawing in AutoCAD. Figure 5-74 shows the floor plan with these pieces of furniture. If you draw the bed shown here, try using the Spline tool for the curved, turned-down sheets. It’s on the expanded Draw panel. You’ll see how it works after a little experimentation.
Figure 5-75 shows a gasket that is symmetrical around its vertical and horizontal axes. This symmetry will allow you to use the MIRROR
command to create much of the drawing.
The diagram in Figure 5-76 summarizes the steps.
To draw the gasket, set Linear Units to Engineering with a precision of 0′-0.00″. Set Angular Units to Decimal with a precision of 0.00. Now, follow these steps:
LINE
command to draw a rectangle 4″ wide and 3″ high.FILLET
with a radius set to 1″ on the upper-left corner of the original rectangle.FILLET
with a radius of 0.50″ on the intersection of these two lines, retaining the right and lower segments.TRIM
to remove unneeded lines.MIRROR
to flip the shape down.MIRROR
again to flip the shape to the right.05-Gasket.dwg
.Figure 5-77 shows a parking lot partially bordered by sidewalks and streets.
You’ll get a lot of practice using the OFFSET
and FILLET
commands while completing this drawing. Guidelines will help you, so don’t be afraid to use them. Note the tip at the end of this section. Here’s a summary of the steps:
90
°, and turn it on.10
, Grid to 0
, and Drawing Limits to 400, 250
.LINE
command and relative Cartesian coordinates, as you did in Chapter 3.FILLET
and TRIM
to finish the drawing.I05-ParkingLot.dwg
(M05-ParkingLot.dwg
).
STRETCH
commandCIRCLE
and ELLIPSE
commandsMOVE
and COPY
commands3.138.120.136