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Cut feature A Cut feature may create multibodies, either intentionally or unintentionally. When it does happen, the Bodies To Keep dialog box appears to enable you to select which bodies you intend to keep. The Bodies To Keep dialog box is shown in Figure 26.17. This dialog box was formerly called Resolve Ambiguity, which was not as descriptive as Bodies To Keep. FIGURE 26.17 The Bodies To Keep dialog box Notice that the Bodies To Keep settings are also configurable, and so different bodies can be kept in different configurations, which is very useful. Split feature Of all of the features in SolidWorks, the Split feature is one of the most contentious and controver- sial. In some situations, it is positively dangerous, and can cause a lot of data loss if you are not aware of the workarounds to make it work properly. Endless forum discussions are devoted to this one feature that most SolidWorks users probably do not even use. The Split feature has essentially three functions: n To split a single solid body into multiple solid bodies using planes, sketches, and surface bodies n To save individual solid bodies out to individual part files n To reassemble individual part files that are saved out into an assembly where the parts are all positioned in the same relative position as their corresponding bodies 748 Using Advanced Techniques Part VI 36_080139 ch26.qxp 3/26/07 5:33 PM Page 748 The last two functions of the Split feature are addressed in Chapter 28, and these are the most con- troversial areas of its functionality. The part of the Split feature that concerns this chapter is the first function mentioned, which is splitting a single solid body into multiple bodies using a sketch, a plane, or a surface body. Splitting with a sketch When using a sketch, the Split process works like this: 1. Create a sketch with an open or closed loop; even a mixture of open and closed profiles will work. If it is open, then the endpoints have to either be on an exterior edge or hang- ing off into space; they cannot actually be inside the boundaries of the solid. 2. Initiate the Split feature from the Features toolbar or from the menus at Insert ➪ Features ➪ Split. You can do this with the sketch active, with the sketch inactive but selected, or with nothing selected at all. 3. Click the Cut Part button. This does not actually cut anything; it only previews the split. When this is done, the resulting bodies appear in the window below, and callout flags are placed on the part in the graphics window. These flags are often useless because they tend to point to the borders between two different bodies in such a way that it is completely ambiguous as to which body they are indicating. However, in the example shown in Figure 26.18, the result is very clear. FIGURE 26.18 Using the Split feature 749 Modeling Multibodies 26 36_080139 ch26.qxp 3/26/07 5:33 PM Page 749 Check marks next to the body in the list indicate that the body will be split out. The lack of a check mark does not mean anything. For example, in Figure 26.18, notice that two boxes are checked, but this will result in a total of four bodies. Body 3 and Body 4 are free. If only Body 1 were selected, then the result would be only two bodies. The callout flags and the bodies list where <None> is shown are looking for a path and filename to save the body out to a file. Again, this functionality is covered in Chapter 28 with the Master Model information. The Save All Bodies button simply puts check marks in all of the boxes. If the Resulting Bodies box contains more than ten bodies, then the interface changes slightly, as shown in the image to the right in Figure 26.18. In past releases, the list box did not contain the slider bar; only the Next 10 button appeared, and it was easy to miss, not being a usual interface technique for accessing lists that were longer than the box in which they appeared. The Consume Cut Bodies option removes, or consumes, any of the bodies that have a check mark. If you used the Split feature a couple of releases ago, the default was for it to consume all bodies. The current situation is a big improvement. Splitting with a plane Splitting with a plane gives the same type of results and uses the same options as splitting with a sketch. However, you never have to worry about the plane being extended far enough, because the cut is made from the infinite planar extension of the plane. The only thing you have to worry about with a plane is whether it intersects the part. Splitting with a surface body Surface bodies are used to split solid bodies for a couple of reasons. In the part shown in Figure 26.10, a surface body was used to make the split instead of a sketch or a plane, because both of those entities split everything in an infinite distance either normal to the sketch plane or in the selected plane. A surface body only splits to the extents of the body. If you look closely at the part, you will notice that a plane or sketch would lop off one side of the sphere on top of the object, but the small planar surface is limited enough in size to only split what is necessary. Another advantage to using a surface body is that it is not limited to a two-dimensional cut. The surface itself can be any type of surface, such as planar, extruded, revolved, lofted, or imported. Taking this a step further, the surface is not limited to being a single face, or a body resulting from a single feature; it could be made from several features that are put together as long as it is a single body and all of the outer edges of the surface body are outside the solid body. If you examine the mouse part shown in Figure 26.1, you will notice that it has splits made from multi-feature surface bodies. Splitting with surface bodies is mentioned here because this is where the Split function is dis- cussed, even though the surfacing functions have not been covered yet. It may be useful to read parts of this book out of order; because of the interrelatedness of all of the topics, it is impossible to order the topics in such a way that nothing ever refers to a topic that has not yet been covered. 750 Using Advanced Techniques Part VI 36_080139 ch26.qxp 3/26/07 5:33 PM Page 750 For more information about surface bodies, see Chapter 27. Insert Part feature The Insert Part button can be found on the Features toolbar, or you can access this feature through the menus at Insert, Part. Insert Part enables you to insert one part into another part. When inserting the part, you have the option to also insert axes, planes, cosmetic threads, and surface bodies. All solid bodies from the selected part are automatically brought into the current part. The PropertyManager interface for the Insert Part feature is shown in Figure 26.19. FIGURE 26.19 The Insert Part PropertyManager This feature has two major functions: inserting a body as the starting point for a new part, and inserting a body to be used as a tool to modify an existing part. Notice that the basket part shown in Figure 26.11 and Figure 26.12 also uses Insert Part to put together bodies to form a finished part. When you use Insert Part, there is no Insert Part feature that becomes part of the tree. Instead, a part icon is shown with the name of the part being inserted. Also notice in Figure 26.19 that the Launch Move Dialog option displays at the bottom, and is on by default. This option launches the Move dialog box after you insert the part. This Move feature is the same as the Move/Copy Bodies feature, with the same options (translate or rotate by distance or angles, or use assembly-like mates to position bodies). Insert Part is used in many situations, some of which are covered in Chapters 11 and 28 in the sec- tion on Master Model and Skeleton techniques. CROSS-REF CROSS-REF 751 Modeling Multibodies 26 36_080139 ch26.qxp 3/26/07 5:33 PM Page 751 Secondary operations One of the commonly used techniques has to do with secondary operations. For example, you may have designed a casting that needs several machining operations after it comes from the foundry. The foundry needs a drawing to produce the raw casting, and the machine shop needs a different drawing to ream and tap holes, spot face areas, and so on. Although you can use configurations to do this, using Insert Part is another way. This has nothing to do with multiple body techniques, but this is the only place where Insert Part is covered in much detail. One of the advantages of using Insert Part is that you no longer carry around the overhead of all of the features in the parent part. It is as if the inserted part were imported. The configurations method forces you to carry around much more feature overhead. Of course, the downside is that now there is an additional file to manage, but this can be an advantage because many companies assign different part numbers to parts before and after secondary operations. Starting point Looking back to the mouse shown in Figure 26.1, the main part has been split into several bodies. You can use Insert Part to insert the whole mouse into a new part where all of the bodies except one are deleted, and then the remaining body serves as the starting point for a new part. Many additional features are needed on all of the bodies that make up the mouse, such as assembly fea- tures, cosmetic features, functional features, and manufacturing features. Managing Bodies Managing bodies in SolidWorks is not as clean a task as managing parts in an assembly. As you work with bodies, you will discover some real surprises in how bodies are managed. Hopefully in this section, I can prepare you for some of the more problematic surprises. Body folders The top of the FeatureManager includes a pair of folders, one called Solid Bodies, and the other called Surface Bodies. These folders are only there if you have solids or surfaces in the model, and they reflect the state of the model at the current position of the Rollback bar. As a result, the folders can change and even disappear as you roll the tree back and forth in history. Figure 26.20 shows the top of a FeatureManager that has both solid and surface body folders. Notice that the number in parentheses after the name of the folder shows how many bodies are in that particular folder. An odd fact about these folders is that you are allowed to rename the folders, but the name changes never remain. If you go back to rename the folder again, the name that you assigned is dis- played; you cannot name another feature with the name that you assigned, but it is never displayed as the name of the folder. 752 Using Advanced Techniques Part VI 36_080139 ch26.qxp 3/26/07 5:33 PM Page 752 FIGURE 26.20 Body folders in the FeatureManager By right-clicking either of the bodies folders, you can select the Show Feature History option, which shows the features that have combined to create the bodies. This view of the FeatureManager is shown in Figure 26.21. This option is very useful when you are editing or troubleshooting bodies. FIGURE 26.21 Using the Show Feature History option Figure 26.21 also shows the other options in the RMB menu. All of the bodies in the folder can be alternately shown or hidden from this menu, as well as deleted. While the Hide or Show state of a body does not create a history-based feature in the tree, the Delete feature does, as discussed previously. The Insert Into New Part feature and the Save Bodies feature are discussed in Chapter 28. 753 Modeling Multibodies 26 36_080139 ch26.qxp 3/26/07 5:33 PM Page 753 You can expand the Display pane in parts, in order to show display information for bodies. In Figure 26.22, the Display pane shows the colors assigned to the solid bodies, as well as the fact that several surface bodies exist but are hidden. FIGURE 26.22 The Display pane showing information about solid and surface bodies The folders also make bodies easier to identify, especially when combined with the setting found at Tools, Options, Display/Selection, Dynamic Highlight From Graphics View. This setting quickly turns the body outline red if you move the mouse over the body in the body folder. Hide or show bodies You can hide or show bodies in one of several ways. I have already described the method of using the bodies folders to hide or show all of the bodies at once, but you can also RMB click individual bodies in the folders to hide or show from there as well. Also, if you can see a body in the graphics area, then you can RMB click the body and select Hide under the Body heading. This works for both solids and surfaces. When you are hiding or showing bodies from the FeatureManager, and not using the bodies fold- ers, but rather using the features themselves, things get a little complicated. If you want to hide or show a solid body, then you can use any feature that is a parent of the body to hide or show the body. For example, you can use the Shell feature in the mouse model to hide or show all of the bodies of which it is a parent. Although this technique works well for solid bodies, surface bodies are a different story. In order to show or hide a surface body using features in the FeatureManager, you have to select the very last feature that was used on that particular body. For example, in the mouse model, Fillet 5 was the last feature to touch that particular body, but Surface-Offset1 was the first feature of that body, and it cannot be used to hide or show anything. This is an example of the inconsistency that causes confusion with managing bodies in SolidWorks. 754 Using Advanced Techniques Part VI 36_080139 ch26.qxp 3/26/07 5:33 PM Page 754 Other facts that you need to know about bodies and their hide or show states are that the Hide or Show feature is both configurable and dependent on the rollback state. As a result, if you hide a body, and then roll back, it may appear again, and you will have to hide it. Then, if you roll for- ward, the state changes again. Also, a body can be hidden in one configuration, and then when you switch configurations, it remains hidden. This makes it rather frustrating to work with bodies. To me, it would be nice if bodies had simple on/off toggles that were neither intelligent nor tricky. Some features exclude bodies if the bodies are hidden when you edit the feature. Be careful of this, and be sure to show all of the bodies that are used in a particular func- tion before you edit it. For example, if a body is hidden, and you create a new extrude that touches the hidden body, then the new body does not merge with the hidden one even if the Merge option is on . If the hidden body is then shown and you edit the second body, then the bodies will merge upon the closing of the second body. Deleting bodies I have already mentioned that you can delete bodies using the Delete Bodies feature, and that this feature sits in the tree at a specific point in the history of the part. Delete Bodies does not affect file size or rebuild speed. In fact, I find it difficult to come up with examples of when you should use it, other than the situation already mentioned with the Rib fea- ture, or if a throwaway body somehow remains in the part. Some people use this feature to clean up the organization of the tree, which could be useful if there are many bodies in the part. Other users insist on keeping the tree free of extraneous bodies, and so they immediately delete bodies that have been used. To me, this technique replaces one kind of clutter with another, and means that tools that should be available to you (solid or surface bodies) are not available unless you reorder the Delete Body feature down the tree and/or roll back. In any case, this is really a matter of personal working style, and not of any great importance. Renaming bodies Notice that the bodies that you see in the folders have been named for the last feature that touched that body. That naming scheme is as good as any, except that it means that the body keeps chang- ing names. Even if you deliberately rename a body, the name will change with the next feature that is added to it. This is particularly true when a feature results in a body being split into multiple fea- tures or when the feature combines bodies. This means that body names are also rollback state- dependent, like body colors, and the Hide or Show feature. Tutorials: Working with Multibodies This tutorial contains various short examples of multibody techniques in order from easy to more difficult. CAUTION CAUTION 755 Modeling Multibodies 26 36_080139 ch26.qxp 3/26/07 5:33 PM Page 755 Merging and local operations This tutorial gives you some experience using the Merge Result option and using features on individ- ual bodies to demonstrate the local operations functionality of multibody modeling. Try these steps: 1. Start a new part, and sketch a rectangle on the Top plane, with the Origin at the midpoint of the line at one end of the rectangle. Size is not important for this exercise. 2. Extrude the rectangle to roughly one-third of its smaller dimension. 3. Open a second sketch on the Top plane. Hide the first solid body by right-clicking it in either the FeatureManager or the graphics window. 4. Show the sketch for the first feature, and draw a second rectangle on the far side of the rectangle from the Origin. Make sure that the second rectangle gets two coincident rela- tions to the first sketch, at two corners so that the rectangles are the same width. When the sketch is complete, hide the sketch that was shown. 5. Extrude the second rectangle to about two-thirds of the depth of the first rectangle. Notice that the Merge option was not changed from the default setting of On for the second extrude, but because the first extrude was hidden, the second extrude did not merge with it. Be careful of subsequent edits to either of the features if the first body is shown, because this may cause the bodies to merge unexpectedly. In this tutorial, the bodies are later merged intentionally. In this case, the tutorial uses a bug in the software as an advantage, but ideally what you should do (in case the bug is fixed at some point) is to deselect the Merge option of the second extrude. 6. Shell out the second extrusion by removing two adjacent sides, as shown in Figure 26.23. One of the sides is the top and the other is the shared side with the hidden body. The body that should be hidden at this point is shown as transparent in the image for refer- ence only. The body was made transparent to make it easier to select the face of the sec- ond body. FIGURE 26.23 Shelling two sides of a block NOTE NOTE 756 Using Advanced Techniques Part VI 36_080139 ch26.qxp 3/26/07 5:33 PM Page 756 7. Show the first body either from the Solid Bodies folder at the top of the tree or from the RMB menu of the first solid feature in the tree. 8. Shell the bottom side of the first body, so that the cavities in the two bodies are on oppo- site sides. 9. Combine the two bodies using the Combine tool found at Insert ➪ Features ➪ Combine. Select the Add option and select the two bodies. Click OK to finish the feature. Figure 26.24 shows the finished part. FIGURE 26.24 The finished part Splitting and patterning bodies This tutorial guides you through the steps to delete a pattern of features from an imported body, separate one of the features, and then pattern it with a different number of features. This intro- duces some simple surface functions, in preparation for Chapter 27. Follow these steps: 1. Open the Parasolid file from the CD-ROM called Chapter 26 – Bonita Tutorial.x_t. 2. Using the Selection Filter set to filter Face selection (the default hotkey for this is X), select all of the faces of the leg. You can use window selection techniques to avoid click- ing each face. 3. Click the Delete Face button on the Surfaces toolbar, or access the command through the menus at Insert ➪ Face ➪ Delete. Make sure that the Delete And Patch option is selected. The selected faces and the Delete Face PropertyManager should look like Figure 26.25. Click OK to accept the feature. 757 Modeling Multibodies 26 36_080139 ch26.qxp 3/26/07 5:33 PM Page 757 [...]... 27 37_ 080 139 ch27.qxp Part VI 3/26/07 5:35 PM Page 7 78 Using Advanced Techniques FIGURE 27.12 Using Replace Face Untrim Surface The Untrim Surface is discussed in the terminology section of this chapter You can use it either selectively on edges or on the entire surface body 7 78 37_ 080 139 ch27.qxp 3/26/07 5:35 PM Page 779 Working with Surfaces Parting Surface The Parting Surface is part of the SolidWorks. .. option In previous versions, when this option was turned on, SolidWorks did not notify you if it did not work If the selection could not be knit into a solid, then it would simply turn off the option You would have to look into the bodies folder to see if it was turned into a solid or remained as a surface In SolidWorks 2007, this 771 27 37_ 080 139 ch27.qxp Part VI 3/26/07 5:35 PM Page 772 Using Advanced... to SolidWorks 2007 It most resembles a loft, but also has elements of the fill surface It is limited to a four-sided patch, and requires you to select edges or sketch elements in two different directions, directly relating to the NURBS scheme that was discussed earlier in this chapter This feature works with only one set of edges selected 767 27 37_ 080 139 ch27.qxp Part VI 3/26/07 5:35 PM Page 7 68 Using... a history-based feature in the model tree FIGURE 26.26 Using the Delete Hole option 7 58 36_ 080 139 ch26.qxp 3/26/07 5:33 PM Page 759 Modeling Multibodies NOTE Delete Hole is really a surface feature called Untrim Untrim is discussed more in Chapter 27, but you can use it to restore original boundaries to a surface 8 Once you delete the hole from the surface body, change the color of the surface body... few basic ideas, but you will find as many surfacing techniques as you will find surfacing designers The topic for this section could be the topic for an entire book on its own 780 37_ 080 139 ch27.qxp 3/26/07 5:35 PM Page 781 Working with Surfaces Instead, what I show here are a few broad categories of techniques that you can apply to particular situations Up to Surface/Up to Body Some situations seem... a part using an offset surface to extrude text up to where the text spans more than a single surface This is a very common application, even if it is not text that is being 781 27 37_ 080 139 ch27.qxp Part VI 3/26/07 5:35 PM Page 782 Using Advanced Techniques extruded The part that was used in Figure 27.15 is on the CD-ROM in the materials for Chapter 26, and is called Chapter 26 – Up To Body.SLDPRT FIGURE... could make the cut with multiple cut features, or even with a surface Figure 27.16 shows a part that is cut with a surface FIGURE 27.16 Using the Cut With Surface feature on a part 782 37_ 080 139 ch27.qxp 3/26/07 5:35 PM Page 783 Working with Surfaces When cutting with a surface, the edges of the surface must be outside of the body that is being cut With sketches, it is advisable to have more sketch than... modeling is point mesh data This comes from systems such as 3DSMax, which create a set of points that are joined together in triangular facets, and can be represented in SolidWorks as an STL (stereolithography) file When displayed in SolidWorks, this data looks very facetted or tessellated into small, flat triangles, but when viewed in software that is meant to work with these kinds of meshes, it looks... not a coincidence that these are the types of shapes that can be flattened by the Sheet Metal tools 765 27 37_ 080 139 ch27.qxp Part VI 3/26/07 5:35 PM Page 766 Using Advanced Techniques Ruled surface Developable surfaces are a special type of a broader range of surface called ruled surfaces SolidWorks has a special tool for the creation of ruled surfaces that is described in detail in the next section...36_ 080 139 ch26.qxp Part VI 3/26/07 5:33 PM Page 7 58 Using Advanced Techniques FIGURE 26.25 The Delete Face PropertyManager 4 Repeat the process for a second leg, leaving the third leg to be separated from the rest of the part and . corresponding bodies 7 48 Using Advanced Techniques Part VI 36_ 080 139 ch26.qxp 3/26/07 5:33 PM Page 7 48 The last two functions of the Split feature are addressed in Chapter 28, and these are the. indicating. However, in the example shown in Figure 26. 18, the result is very clear. FIGURE 26. 18 Using the Split feature 749 Modeling Multibodies 26 36_ 080 139 ch26.qxp 3/26/07 5:33 PM Page 749 Check marks. tree. FIGURE 26.26 Using the Delete Hole option TIP TIP 7 58 Using Advanced Techniques Part VI 36_ 080 139 ch26.qxp 3/26/07 5:33 PM Page 7 58 Delete Hole is really a surface feature called Untrim.