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Core Out the Part 119 FIGURE 3.48 Defining the bottom wall thickness of the cutout 3. Do the same on the two vertical rectangle segments that are closest to the part edges. 4. Now all that is left is to define the height of the cutout. Select one of the two segments on the side of the rectangle, and place the dimen- sion. Set the height of the rectangle to be 2 inches in the Modify win- dow, as shown in Figure 3.49. FIGURE 3.49 Fully defined sketch of the cutout 5. Exit the sketch by clicking the Exit Sketch button in the confirma- tion corner. Cut Out the Cavity Since you started the process by clicking the Cut-Extrude button prior to cre- ating the sketch of the cutout, when the sketch was exited, the Extruded Cut command automatically initiated. This approach reduces the number of mouse clicks and in the long run will save you time while you are modeling, which is always a good thing. 505434c03.indd 119 1/27/10 1:50:25 PM Chapter 3 • Creating Your First Part 120 1. Press Ctrl+7 on your keyboard, or select the isometric view in the Heads-up View toolbar. 2. In the Extrude PropertyManager, set the depth of the extrusion to be 1.00 inch deep, and click the green check mark to complete the action, as shown in Figure 3.50. FIGURE 3.50 Setting the depth of extrusion in the Extrude PropertyManager 3. Press Ctrl+S on your keyboard or press the Save button on the menu bar to save the changes you have made to the model. Figure 3.51 shows an isometric view of the model so far. FIGURE 3.51 Part model showing a rectangular-shaped cavity cut out from the bottom Add Cutout for Electronics Cover When the lamp is manufactured and in use, the electronics and wiring will be housed in the cavity and cannot be allowed to just fall out. This could be a huge issue for the consumer, not to mention a hazard. This is why you need to add a 505434c03.indd 120 1/27/10 1:50:31 PM Core Out the Part 121 cutout that a small plastic cover will sit in. The cutout has to be recessed since this is the side of the base that will ultimately be placed on a desktop, and if it is above the surface of the base, the base will tilt to one side and be very unstable. To add the cutout, do the following: 1. Press Ctrl+6 or select the bottom view in the Heads-up View toolbar. 2. Press S on the keyboard, and select Cut-Extrude in the shortcut bar. 3. Select the bottom face of the lamp base model to insert a blank sketch. 4. Since the cutout for the cover will follow the outline of the cavity cutout, you’ll offset the edge rather than create a new rectangle. Press S on the keyboard, and select the Offset Entities button on the shortcut bar. The Offset Entities command allows you to create sketch entities that are offset by a specified distance from existing sketch entities, model edges, or model faces. Using the Offset Entities tool, you’ll off- set the edges of the cavity you created earlier to ensure that the geom- etry for the cover cutout will be updated as dimensions are changed. 5. In the Offset Distance field in the PropertyManager, enter the value .1. This is the distance a line will be created from the edge of the cavity. 6. Ensure that the Add Dimensions option is selected in the PropertyManager. Without this option selected, the newly created sketch entities will not be defined. Also, make sure that the other selected options shown in the previous image are selected. 7. In the graphics area, select the bottom face of the cavity to offset the four edges by the specified dimension. 505434c03.indd 121 1/27/10 1:50:35 PM Chapter 3 • Creating Your First Part 122 8. Click the green check mark to exit the command and create the off- set, shown in Figure 3.52. FIGURE 3.52 Creating an offset entity The lines that are created by the Offset Entities command take on the Offset Entities relation, eliminating the need for additional relations such as Horizontal or Vertical since these relations should have been applied to the original edges. Also, by selecting the Add Dimensions option in the PropertyManager, you’re able to create a fully defined sketch without the need to add more dimensions. With the sketch fully defined, all that is left to do is to create the extruded cut. 9. By clicking the Extruded Cut command prior to creating the sketch, you eliminated a couple of extra steps. Once the sketch is complete, click the Exit Sketch icon in the confirmation corner to initiate the Extruded Cut command. 10. In the Depth field in the PropertyManager, enter the value of .1, and make sure that the Blind end condition is selected. Since these are the only options you need for this feature, click the green check mark to make the cut. Figure 3.53 shows the part model with the offset entity. FIGURE 3.53 Part model showing extruded cut to use for cover cutout 505434c03.indd 122 1/27/10 1:50:41 PM Core Out the Part 123 Add Holes for Wiring In the previous couple of sections, you created a cavity that will eventually be used to house the wiring and electronics for the lamp. But you may have noticed that there is nowhere for the wiring to go. Well, you do, in fact, need to remedy that, and you are going to do it by creating a hole in the boss from earlier in the chapter to pass the wires up to the bulb subassembly. You’ll also create a hole in the back of the lamp base that will be used for the AC plug cord. First is the hole for running the wires up to the bulb assembly and the counterbore that will be necessary for the shaft nut. Sketch a Circle with a Defined Diameter Here are the steps for adding a hole for the counterbore: 1. If you changed the display style of the part back to Shaded With Edges, you will need to return to the Hidden Lines Visible view in order to cre- ate the next couple of features. In the Display Style pull-down on the Heads-up View toolbar, select the Hidden Lines Visible option. 2. Press S on your keyboard, and select Extruded Cut from the shortcut bar. 3. Rotate the part to show the bottom, and select the face on the bottom of the wiring cavity to insert a sketch for the extruded cut, as shown in Figure 3.54. FIGURE 3.54 Selecting a face for an extruded cut sketch The following step is another example of how design intent affects how a sketch is created. In the next step, you can easily decide to offset the edge of the round boss to specify the wall thickness, if that was indeed what your design intent required. Since the hole going through the boss and counterbore require that the shaft and shaft nut have enough room, you must instead specify the hole diameter. 505434c03.indd 123 1/27/10 1:50:44 PM Chapter 3 • Creating Your First Part 124 The easiest way to do this is to create a circle and specify the circle diameter in the sketch. 4. Press S on your keyboard, and select the Circle button in the shortcut bar. Press Ctrl+8, or select Normal To in the Heads-up View toolbar. 5. To ensure that the circle drawing in the sketch is concentric with the boss, you will specify that the center of the circle shares the same cen- ter point of the boss. Without clicking the mouse button, hover over the edge of the boss with the mouse pointer until the four quadrants of the circle are shown with small yellow diamonds and the center is displayed with a small circle with a cross, as shown in Figure 3.55. FIGURE 3.55 Drawing a circle concentric with the boss 6. Move the mouse pointer over the center mark for the boss, and press and release the left mouse button. 7. Drag the mouse slowly from the center point to create the circle. When the radius value displayed next to the mouse pointer shows the R value to be somewhere close to 0.500, click and release the left mouse button, as shown in Figure 3.56. 8. Press the S key, and click the Smart Dimension button in the shortcut bar. 9. Select the circumference of the circle with the mouse pointer, and click and release the left mouse button. Place the dimension on the outside of the circle, and enter 1 in the field of the Modify window. If you properly selected the center of the circle, the circle will be shown as black after applying the dimension, since the location and size of the circle will be fully defined, as shown in Figure 3.57. 505434c03.indd 124 1/27/10 1:50:47 PM Core Out the Part 125 FIGURE 3.56 Drawing the circle, continued FIGURE 3.57 Fully defined concentric circle The sketch with the 1.00≤ circle is what will become the counterbore that makes room for the shaft nut. When the lamp is assembled, the threaded end of the shaft will be held into place securely fastened to the lamp base with a nut. Execute an Extruded Cut for the Counterbore Now it is time to create the actual extruded cut feature that will become the counterbore. Here’s how: 1. Click the Close Sketch icon in the confirmation corner in the upper- right corner of the graphics area. Once the sketch is exited, the Extruded Cut command will automatically be initiated. To make the next couple of steps easier, press Ctrl+7 on your keyboard to switch to an isometric view. 2. In yet another example of design intent dictating the modeling of fea- tures, instead of creating a blind extrusion, you will create the feature 505434c03.indd 125 1/27/10 1:50:56 PM Chapter 3 • Creating Your First Part 126 to ensure that a specified wall thickness is met. To do this, you will need to select another end condition in the PropertyManager for the Extruded Cut command. Click the End Condition field to display the available ways to terminate the feature. 3. To ensure that the wall thickness is properly specified, select the Offset From Surface option in the End Condition field. 4. Although you should not have to select it, you should at least be aware that the Face/Plane field in the PropertyManager is highlighted and expecting the selection from the graphics area, as shown in Figure 3.58. FIGURE 3.58 Face/Plane field in PropertyManager The Face/Plane field, when using the Offset From Surface end con- dition, is the one that will be used to create the theoretically offset terminating plane for the feature created. Select the top face of the boss at the top of the lamp base, as in Figure 3.59. 5. The Offset Distance setting must now be specified in the PropertyManager. As with the Face/Plane field, you should not have to select the field in order to input the value since it should automatically gain focus after specifying the face of the boss. In the Offset Distance field, enter the value .125 to represent the thickness 505434c03.indd 126 1/27/10 1:50:59 PM Core Out the Part 127 of material that will be spared after creating the cut, as shown in Figure 3.60. After entering the value, click the green check mark to create the extruded cut. FIGURE 3.59 Specifying the face for the Extruded Cut offset FIGURE 3.60 Offset Distance field in PropertyManager The last feature was the counterbore that will be used for the shaft nut. Now you need to create the hole that allows the shaft to mount to the lamp base. Create the Through Hole for the Lamp Shaft This feature, like the counterbore, will be defined with another sketch of a circle with the diameter specified in order to ensure that the shaft will fit properly in place. At this point, you can also switch the view display back to Shaded With Edges since it will no longer be necessary to see the hidden lines of the model. 505434c03.indd 127 1/27/10 1:51:07 PM Chapter 3 • Creating Your First Part 128 1. Once again, press S on your keyboard, and click the Extruded Cut command in the shortcut bar. This time, select the top face of the boss to insert a sketch for the extruded cut, as shown in Figure 3.61. FIGURE 3.61 Selecting a face on which to draw the sketch 2. While in the sketch, open the shortcut bar, and click the Circle command. 3. Display the center mark for the edge of the boss by hovering over the edge with the mouse pointer. Specify that the center point of the circle will share the center point with the boss, as in Figure 3.62. FIGURE 3.62 Creating the concentric circle for the thru hole 4. Create the circle, and specify the diameter to be .7, as in Figure 3.63. Exit the sketch to initiate the Extruded Cut command. 505434c03.indd 128 1/27/10 1:51:13 PM [...]... feature in the FeatureManager, a red circle with an X is displayed This is how SolidWorks displays that there is an error with the feature 137 138 C h a p t e r 3 • C r e a t i n g Yo u r F i r s t P a r t There are many reasons a feature might fail, and sometimes trying to figure out the error can be a little frustrating SolidWorks does provide you with information about the error to aid you in debugging... A fillet is often an edge of a part that is rounded to a specified radius Depending on whether the fillet is on the outside or inside corner, the manufacturing process will differ, but the process in SolidWorks is the same A chamfer is is used a lot less often in consumer products because it is not as “soft” as a fillet, but removing the edge is the same A chamfer is used to break a sharp edge with... slightly larger than the space between the boss and the edge of the part There are two ways you could have avoided this issue; the first is using a smaller radius for the fillet If the fillet was smaller, SolidWorks wouldn’t have needed to change the geometry of the fillet to move around the boss The second way you could have avoided this issue was to create the fillet before you added the boss 135 C h... snapped into the hole to protect the cord, you should still make sure that the features on this lamp base are as accurate as possible At a later date when you become more comfortable with modeling parts in SolidWorks, it would be great practice to design these components to finish your assembly Here’s how to make that hole: 1 Click the Extruded Cut command in the shortcut bar, and select the back face of... FeatureManager This was caused because Fillet4 could no longer find the original edge that was used to create the feature Being able to fix errors in the FeatureManager design tree is an important skill when using SolidWorks, and this gives you a great opportunity to learn how easy it is to do Here’s how to correct the error by moving the fillet features back in time: 1 In the FeatureManager design tree, select... u r F i r s t P a r t F i g u r e 3 8 9 Adding a chamfer to the AC plug hole 12 Click the green check mark to create the chamfer Congratulations! You have just created your first 3D model in SolidWorks If you haven’t already done so already, save your model by clicking the Save button on the menu bar or by pressing Ctrl+S on your keyboard This model that you have created will be used in the... extremely helpful to be able to know how to quickly find and use the tools You can find a complete version of the exercise as Base,Lamp.SLDPRT on the companion website for this book: www.sybex.com/go /solidworks2 010ner.com or on this website: www.swner.com A r e Yo u E x p e r i e n c e d ? Are You Experienced? Now You Can… EE Create a new part model EE Start with a base extrusion EE Create simple sketches . accurate as possible. At a later date when you become more comfortable with modeling parts in SolidWorks, it would be great practice to design these components to finish your assembly. Here’s. is on the outside or inside corner, the manufacturing process will dif- fer, but the process in SolidWorks is the same. A chamfer is is used a lot less often in consumer products because it is. avoided this issue; the first is using a smaller radius for the fillet. If the fillet was smaller, SolidWorks wouldn’t have needed to change the geometry of the fillet to move around the boss. The