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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] : 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 ssss1 and fillets in ssss1.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] : .75Select object to offset or [Exit/Undo] : 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] : 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] : 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.