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When your drawing is properly set up, you’re ready to draw some objects. In this example, you use the Line command to draw a steel base plate and column, the Circle command to draw an anchor bolt, and the POLygon command to draw a hexagonal nut.

AutoCAD, like most CAD programs, uses layers as an organizing principle for all objects you draw. Chapter 9 describes layers and other object properties in detail. For now, think of layers as sheets of transparent plastic lying on top of the drawing. You can hide or display individual drawing elements by simply removing or replacing their particular sheet of plastic.

In this example, you create separate layers for the base plate, column, anchor bolts, nuts, and crosshatching. This might seem like layer madness, but when you’re creating complex drawings, you need to use layers properly to keep everything organized.

The following steps demonstrate how to create and use layers, as well as how to draw lines, circles, rectangles, and polygons. You also see how to move, copy, mirror, offset, and apply fillets.

1 Complete the drawing setup in the earlier section “A Simple Setup.”

2 Prepare to create the five layers you will use to organize the objects that will make up the base plate example by invoking the LAyer command.Do one of the following: On the Layers panel of the Home tab, click the Layer Properties button.The Layer Properties button is at the left edge of the Layers panel.Enter LA from the keyboard.As you type, a list of commands that start with LA appears near the cursor. The full command name is LAYER, but as soon as LA is highlighted, press Enter.The LAyer command starts and AutoCAD displays the Layer Properties Manager palette, as shown in Figure 3-4. If you want to move any palette to a different screen location, just move the cursor to the vertical bar on the palette's left edge and then drag the palette to a new location.FIGURE 3-4: Creating a new layer.

3 Follow these steps to create the needed layers:Click the New Layer button.It’s the leftmost of the group of four buttons that include the green check mark and the red X. AutoCAD adds a new layer to the list and gives it the default name Layer# where # is a number. For the first layer, the default name is Layer1 (see Figure 3-4).Name That Layer.Type Plate as the name of the first layer on which you’ll draw the base plate, and press Enter.Click the color swatch or name (white) in the Color column of the new Plate row.The Select Color dialog box appears, as shown in Figure 3-4.Click the fourth color square (cyan/light blue, index color 4), for the first layer in the single, separate row to the left of the ByLayer and ByBlock buttons, and then click OK.The Select Color dialog box closes, and the color for the Plate layer becomes cyan.With Layer Properties Manager still open, repeat Steps 3a through 3d to create four more layers with these names and colors:Layer NameColorColumn5 (blue)Anchor Bolts3 (green)Nuts1 (red)Hatch6 (magenta)FIGURE 3-5: Select Cyan from the standard color tiles.

You don’t have to create a separate layer for every type of object you draw. For example, you can draw both the anchor bolts and nuts on a Hardware layer. Layer names and usage depend on industry and office practices, in addition to a certain amount of individual judgment. Having too many layers is better than having too few, because lumping together two or more layers is much easier than dividing the objects on one layer into two or more layers. I cover working with layers in more detail in Chapter 9.

Start with the objects that will be drawn on the Plate layer by following these steps:

1 Make the Plate layer current before drawing the objects that make up the plate.Double-click the Plate layer name.A green check mark appears beside the layer name, indicating that it’s current. Anything you draw now will be on the Plate layer and will inherit its color.Click the Close button (the X at the upper-left corner of the palette shown in Figure 3-4) to close the Layer Properties Manager palette.The Layer Properties Manager palette can be left open on the screen or reduced to a vertical bar, but you might as well close it because you won’t need it again in this drawing session.

2 Draw the base plate.Start the Line command by clicking its button on the Draw panel of the Ribbon’s Home tab or by typing L and pressing Enter.Draw three lines by responding to AutoCAD’s prompts: LINESpecify first point: 68,7 and press Enter.Specify next point or [Undo]: Move the cursor to the left and then enter 36 You don’t need to enter a negative value for the second point. AutoCAD knows which way to draw the line because the cursor is located to the left of the first point. Because the Ortho (F8) button is turned on, AutoCAD constrains the cursor to move only exactly horizontally or vertically. In this case, a horizontal line exactly 36 units long is drawn, no matter how far away the cursor is from the first point.Specify next point or [Close Undo]: Move the cursor up and then enter 36Specify next point or [Close Undo]: Move the cursor to the right and then enter 36Specify next point or [Undo]: CEntering C (uppercase or lowercase) closes the line back to the starting point.

If you didn’t complete the previous steps, start from this point by using drawing afd03a-i.dwg, available in the afd03.zip download at www.dummies.com/go/autocadfd19. Download it to a suitable location, click the Application button, and then click Open. Browse to the file.

Time to add a bolt. You first need to change to the Anchor Bolts layer, and then draw the bolt:

1 Go to the Layers panel of the Home tab.

2 Click the arrow at the right-hand end of the Layer drop-down list.The current entry (from the running example) is Plate. Layer names are listed in alphabetical order, not in the order in which you created them.

3 Choose the Anchor Bolts entry to set the Anchor Bolts layer as the current layer. Using the Layer drop-down list, in the upper-right corner of the Layers panel of the Home tab of the Ribbon, saves you from having to open Layer Properties Manager, select the layer, click the Set Current button, and close Layer Properties Manager when you want to change to a different layer. Becoming an AutoCAD master is all about efficiency. The real heart of all human progress is laziness — we will work hard at finding ways to avoid work.

4 Draw the bolt:Start the Circle command, either from the Draw panel or by simply typing C and pressing Enter.Draw a circle by responding to AutoCAD’s prompts this way: CIRCLESpecify center point for circle or [3P/2P/Ttr (tan tan radius)]: intOf: Move the cursor until it is close to the lower-left corner of the rectangle and then click when a green X appears at the intersection of the two lines.Specify radius of circle or [Diameter]:AutoCAD defaults to the radius of a circle, but you want to specify the diameter, so enter D.Specify diameter of circle: 1.5

5 Save your drawing. AutoCAD automatically backs up your work, but you could still lose the last ten minutes or so. Now is a good time to press Ctrl+S.

Now add a hexagon nut for the bolt:

1 Make the Nuts layer current by using the Layer drop-down list from the Layers Ribbon panel.

2 Start the POLygon command.Its button is either in the upper-right corner of the Draw panel or on the drop-down list with the RECtangle button, depending on which command you last used. You can also type POL and press Enter.

3 Draw a hexagon.Respond to these AutoCAD prompts: POLYGON Enter number of sides <4>: 6Specify center of polygon or [Edge]: cenOf: Click anywhere on the circle.Enter an option [Inscribed in circle/Circumscribed about circle] <I>: C The Inscribed option draws a polygon whose corners touch the circumference of the imaginary circle. The Circumscribed option draws a polygon whose sides are tangent to the circumference of the circle and has nothing to do with a medical procedure. Bolt heads and nuts are normally specified by the width across the flats (unless you own a vintage British car such as a 1937 Rolls-Royce, where Whitworth wrenches are arbitrarily defined by the diameter of the thread), so choose the C option.Move the cursor.The hexagon rotates about its center. You should still have ORTHO turned on, so AutoCAD shows only two possible choices for the vertex of the polygon: horizontal or vertical from the center of the imaginary circle.Move the mouse until a vertex is horizontal from the center of the circle.Respond to this AutoCAD prompt: Specify radius of circle: 1.5Press Enter, and AutoCAD draws the hexagon.

Okay, suppose that you draw the circle and the hexagon in the wrong location. Easy enough. Just move objects to another location as follows:

1 Start the Move command, which is on the Modify panel.When AutoCAD prompts you, respond this way:MOVESelect objects: Click the circle or the hexagon. 1 foundSelect objects: Click the hexagon or the circle. 1 found, 2 totalSelect objects: Press Enter.Specify base point or [Displacement]: 6,6Specify second point or <use first point as displacement>: Press Enter.Like magic, AutoCAD moves the hexagon and the circle six units to the right and six units up.

2 Take a break.Press Ctrl+S to save the drawing. It may be time for a hydraulic break; remember that the mind can’t hold more than the bladder.

There are several different ways to produce additional nuts and bolts. The next two procedures combine to demonstrate one method:

1 Start the COpy command, which is on the Modify panel. Then follow these prompts. COPYSelect objects: p Selects the Previous selection set, being the objects you selected to move. 2 foundSelect objects: Press EnterCurrent settings: Copy mode = MultipleSpecify base point or [Displacement/mOde] <Displacement>: 0,24Specify second point or [Array] <use first point as displacement>: Press Enter.Presto! AutoCAD creates a copy of the circle and the hexagon 24 units above the first set.

2 Start the MIrror command, found on the Modify panel. Then follow the prompts. MIRRORSelect objects: p Selects the Previous selection set, being the first nut and bolt. 2 foundSelect objects: Click the upper circle or the upper hexagon. 1 foundSelect objects: Click the upper hexagon or the upper circle. 1 found, 4 totalSelect objects: Press Enter.Specify first point of mirror line: midof: Select the upper horizontal line.Specify second point of mirror line: Make sure Ortho (F8) is still on and pick a point above or below the upper line.Erase source objects? [Yes/No] <N>: Press Enter.That was a little faster than drawing four circles and four hexagons by hand, wasn’t it?

3 Draw the column. Start by selecting Column to set it as the current layer.On the Layers panel of the Home tab, click the Layer drop-down list to display the list of layers. Select Column to set it as the current layer.Now you’re ready to create the hollow column, starting with its outside profile. Be sure to keep the cursor in the drawing area during this step and the next one.Start the RECtang command, found on the Draw panel. RECTANGSpecify first corner point or [Chamfer/Elevation/Fillet/Thickness/Width]: 44,16Specify other corner point or [Area/Dimensions/Rotation]: @12,18A rectangle is drawn in the middle of the square base plate.Start the FILlet command, on the Modify panel, and watch the command line closely.In this step, you round the corners of the column with the FILlet command and then use OFFset to give it a wall thickness.FILLETCurrent settings: Mode = TRIM, Radius = 0.0000Select first object or [Undo/Polyline/Radius/Trim/Multiple]: rSpecify fillet radius <0.0000>: 2Select first object or [Undo/Polyline/Radius/Trim/Multiple]: pSelect 2D polyline or [Radius]: Move your cursor over the new rectangle and observe how AutoCAD shows you a preview. Click the rectangle.4 lines were filletedYou can pick the lines at each corner that need to be filleted (that’s eight picks), but because the column is a continuous polyline, a more efficient method in this case is to use the FILlet command’s Polyline option to fillet all four corners in one fell swoop. I discuss polylines in Chapter 6 and fillets in Chapter 11.Now give the column a ¾-inch wall thickness. Start the OFFset command. Once again, it’s a Modify item. OFFSETCurrent settings: Erase source=No Layer=Source OFFSETGAPTYPE=0Specify offset distance or [Through/Erase/Layer] <Through>: .75Select object to offset or [Exit/Undo] <Exit>: Click the filleted rectangle. Make sure that the Object Snap (F3) status bar button is toggled off for these next prompts, or AutoCAD may offset the object back on top of itself:Specify point on side to offset or [Exit/Multiple/Undo] <Exit>: Move your cursor over the new rectangle and observe how AutoCAD shows you a preview. Click inside the rectangle.Select object to offset or [Exit/Undo] <Exit>: Press Enter.There you go! You created a hollow structural shape with wall thickness and radiused corners (see Figure 3-6) in just four simple steps.

4 Press Ctrl+S to save the drawing.AutoCAD saves the drawing and renames the previously saved version drawingname.bak — for example, My Plate is Base.bak. AutoCAD uses the filename extension .bak for a backup file. When (not if) things get out of hand, you can always rename the .bak file to .dwg to return to the most recent version.

FIGURE 3-6: Give the column some thickness with OFFSET.

Now that you’ve given Dynamic Input a test drive, turn it off for the rest of this chapter by clicking its button on the status bar so that the button looks dimmed or by pressing F12. If you like using Dynamic Input, toggle it back on.

The drawing afd03b-i.dwg contained in the afd03.zip download includes the base plate and column and one anchor bolt.