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Part III: Working with Assemblies 546 Other types of valid in-context relations include in-context sketch planes and end conditions for extrude features such as Up to Face and Up to Body. Beyond that, you can copy surfaces from one part using the Knit Surface feature or the Offset Surface feature. I discuss surfacing in more detail in Chapter 27. Working in-context When you are working in-context or using in-context data, visual cues offer information about the part that you are working on. The following topics are meant to help you understand what is going on while you are working in-context. Text color When you are working in-context, the FeatureManager text of the part that you are working on turns blue. This should make it immediately obvious first that you are working in-context, and, second, which part is being edited. Part color and transparency You can control the color and transparency behavior of parts in the assembly where a part is being edited in-context by choosing Tools ➪ Options ➪ Colors page. Figure 16.2 shows a detail of this page. The option at the bottom of the dialog box determines whether the colors specified in the list at the top are used or ignored. If they are ignored, the parts are the same colors they would be if you were not using in-context techniques. FIGURE 16.2 Part-color settings for in-context control Chapter 16: Modeling in Context 547 The Tools ➪ Options ➪ Display/Selection Assembly transparency for in context edit controls the transparency of the parts not being edited. Figure 16.3 shows this setting. Forcing the non-edited parts to become transparent helps you keep focus on the part you are editing in the assembly. FIGURE 16.3 Part transparency for in-context control The options in the Assembly Transparency drop-down list are l Opaque Assembly. All parts that are not being edited when an assembly component is being edited in-context turn opaque, even if they are otherwise transparent. l Maintain Assembly Transparency. Leaves all assembly components in their default transparency state. l Force Assembly Transparency. Forces all the parts, except for the one being edited in the assembly, to become transparent. These options reflect personal preference more than anything else, but it is useful to have a reminder as to whether a part is being edited in the assembly or the assembly document is being edited in its own window. Tip The color selected in the box shown in Figure 16.2 controls both the text color and the color of the part shown in the graphics window. n Edit Component button You can use the Edit Component button in two ways. First, after you have created a part in-con- text, seeing the Edit Component button depressed serves as a reminder that you are editing the part rather than editing the assembly. Along with the part color and transparency displays, this is important feedback because assembly functions such as mates, exploded views, and others are not available when you are editing the part. Part III: Working with Assemblies 548 Second, you can use the Edit Component button to begin or finish editing a part that is already in an assembly. When you are editing a part in the context of an assembly, the title bar of the SolidWorks window reflects the fact that you are editing a part in an assembly, the toolbar changes to a part-editing toolbar, and the lower-right corner of the taskbar displays the words Editing Part, as shown in Figure 16.4. Third, a confirmation corner image exists in the upper-right corner of the graphics window when you are editing a part in the context of the assembly. This makes it easier to exit Edit Component mode. FIGURE 16.4 Indicators that you are editing a part in-context Editing a component can also mean editing a subassembly in the context of the top-level assembly. You can create in-context assembly features and mates if necessary; however, you will do this far less frequently than editing parts in-context. Note Creating in-context relations is not the only reason to edit a part or subassembly in the context of the top-level assembly. Sometimes it is simply more convenient to do normal editing when you are in the top-level assembly; this way you can see how the part relates to other parts after making changes in the assembly without making relations between the parts. Editing a subassembly in the context of the upper-level assembly is often useful as well, to see how changing subassembly mates affects the top level. n Chapter 16: Modeling in Context 549 Probably the most common mistake you can make with in-context editing has to do with editing the part versus editing the assembly when they add a sketch. If you intend to add a sketched fea- ture to a part in the context of an assembly, but you fail to switch to Edit Part mode before creating the sketch, then the sketch ends up in the assembly rather than the part; you can only do limited things with a sketch in an assembly. Likewise, if you intend to make an assembly layout sketch, but you do not switch out of Edit Part mode, you end up with a sketch in a part that cannot do what you want it to do. Fortunately, SolidWorks has added a remedy for the first situation. When you make a sketch in the assembly but need to make a feature in the part, you can choose the Propagate feature to parts option in the Feature Scope area of the PropertyManager for the feature, as shown in Figure 16.5. FIGURE 16.5 Propagating an assembly feature to the part Notice in the image on the right that the last sketch in the part appears as derived. This means that the sketch and the feature are still driven from the assembly, but they have been propagated to the part enough to allow the feature to be edited in the part. I wouldn’t go this route just because you made a mistake and it’s simpler to do this than to move the sketch to the part, but it is an option that is valid in some situations. Part III: Working with Assemblies 550 Interestingly, this feature cannot be deleted from the part; you must delete it from the assembly. External reference symbol The external reference symbol appears as a dash followed by a greater-than sign (->). External refer- ences indicate more than just in-context features. You can also create external references by using the Split Part command as well as the Insert Part (base or derived part) or the mirrored part functions. Figure 16.6 shows the expanded FeatureManager for a part with an in-context reference in a sketch. External references can have four states, which Figure 16.6 shows. These are l In-context (->) l Out-of-context (->?) l Locked reference (->*) l Broken reference (->x) FIGURE 16.6 The in-context “carrot” on Extrude1 and Sketch1 In-context -> The in-context symbol signifies that the relation created between two parts within the current assembly is fully resolved. It can find both parts involved in the relationship and the assembly where the relationship that was created is active. Chapter 16: Modeling in Context 551 Out-of-context ->? Out-of-context means that the document — usually but not necessarily an assembly — where the reference was created is not open at the time. It is indicated by an in-context symbol followed by a question mark. You can open the document where the reference was created by clicking the right mouse button (RMB) and selecting the Edit In Context option from the menu. Edit In Context opens either the parent part of an inserted part or the assembly where the reference was created for an in-context reference. When you open the referencing document, the out-of-context symbol changes to the in-context symbol. Locked reference ->* You can lock external references so that the model does not change, even if the parent document changes. The symbol for this is ->*. Other features of the part may be changed, but any external reference within the part remains the way it is until the reference is either unlocked or removed. In the top and base example I mentioned earlier, this means that if the Bottom part is changed, and the external reference on the Top is locked, then the Top will no longer fit the Bottom. One of the best things about locked references is that you can unlock them. They are also flexible and give you control over when updates take place to parts with locked references. Broken reference ->x The broken reference is another source of controversy. Some users believe that if you make in-con- text references, the best way to respond to them is to break them immediately. However, I would argue that using the Break References function is never a good thing to do. I believe that you should remove the reference by editing the feature or the sketch or change it to make it useful. The problem with a broken reference is that it has absolutely no advantage over a locked reference. For example, while locked references can at least be unlocked, broken references cannot be repaired. The only thing that you can do with a broken reference is to use Display/Delete Relations or to manually edit features to completely remove the external reference. Perhaps it would be bet- ter for SolidWorks to replace Break References with a function called Remove References. Would anyone like to make an enhancement request? Best Practice Best practice is to not put yourself in a situation where you are using broken references. Parametric relations should not change if the driving geometry does not change. You cannot selectively lock or break external relations. For example, all the external relations in the part can be locked, all the external relations can be broken, or none of them can be locked or broken. If you need to selectively disable relations, then you should consider suppressing features, sketch relations, end conditions, or sketch planes. n Part III: Working with Assemblies 552 List External References You can access the locked and broken references through the List External References option on the RMB menu of any feature with an external reference symbol. Figure 16.7 shows the name and path of the assembly where the external reference was created, as well as the part names and entity types. FIGURE 16.7 The External References dialog box No External References To access the No External References button on the Assembly toolbar, choose Tools ➪ Options ➪ External References ➪ Do Not Create References External To The Model from the menus. As its name suggests, this setting prevents external relations from being created between parts in an assembly. When you offset in-context edges or use Convert Entities, the resulting sketch entities are created without relations of any type. This lack of references includes the InPlace mate, which is not created when a part is created in- context. As a result, when you add the part to the assembly, if you exit and later re-enter Edit Part mode, SolidWorks reminds you that the part is not fixed in space by displaying the warning shown in Figure 16.8. This message should remind you that in-context features should be used only on parts that are fully positioned in the assembly. Chapter 16: Modeling in Context 553 FIGURE 16.8 The dialog box that warns you about adding in-context relations to an underdefined part External reference settings in Tools ➪ Options The Tools ➪ Options ➪ External References pane of settings controls many aspects of the behavior of external references. I discussed one of these references earlier — No External References — and I discuss the other reference, Multiple Contexts, next. This page in the Tools ➪ Options dialog box is shown in Figure 16.9. FIGURE 16.9 The Tools ➪ Options ➪ External References pane In-context best practice suggestions However, this is a technique that requires a fair amount of discipline, restraint, foresight, and judg- ment. The potential problems associated with overuse or misuse of in-context techniques primarily include performance problems (speed) and lost references due to file management issues. Users may also experience problems with features or sketches that change with each rebuild. The follow- ing section contains best practice suggestions that can help you avoid these situations. Part III: Working with Assemblies 554 Multiple contexts Multiple contexts occur when a part has references that are created in multiple assemblies. By default, multiple contexts are prevented from happening. If you place a part that already has exter- nal references into a different assembly, a warning appears, as shown in Figure 16.10. FIGURE 16.10 The warning message that appears about multiple contexts Although SolidWorks displays many warnings about multiple contexts, you may still run into situ- ations where you need to use them. For example, you may have a subassembly where a part, such as a top plate of a stand, has in-context references to locate a set of mounting holes for legs of the stand. When you place the subassembly into the top-level assembly and mount another assembly to the top plate, another set of in-context holes is required in the top plate. Figure 16.11, at the top, shows the first table and points out the in-context relations. At the bot- tom, the large bracket appears for the machine that is mounted to the table top using more in-con- text relations. The External References dialog boxes for the two different in-context features appear in Figure 16.12. Notice that the Assembly fields at the top of the External References dialog boxes are different. You can only achieve this by selecting the Allow multiple contexts for parts when editing in assembly option shown in Figure 16.9. Note The Tools ➪ Options setting for multiple contexts is a system option. This means that this option is either on or off for every document on a single machine, but when the assembly is used on another machine, the option may be off. n Multiple context modeling is something that should be the exception rather than standard practice. If you do not have all the assemblies open where the in-context references were created, then you will have some out-of-context references. This can make for a troubleshooting nightmare if some- one ever has to try to reconstruct how the assembly is driven. Best Practice The best practice is to avoid creating multiple-context references. If you need to do this, then be very careful about naming files, and remember to turn off the multiple-context option when you have finished creating the reference. n [...]... the assembly from the CD-ROM named Chapter 16 Tutorial Table sldasm 2 Set the colors that are to be used during in-context editing Remember that two settings control this — one at Tools ➪ Options ➪ Colors, and the other at Tools ➪ Options ➪ Display/Selection — as shown in Figure 16. 16 566 Chapter 16: Modeling in Context FIGURE 16. 16 Setting in-context colors 567 Part III: Working with Assemblies Set the... Figure 16. 27 5 76 Chapter 16: Modeling in Context FIGURE 16. 27 Saving the internal virtual components to external parts 21 Exit Edit Part mode using the icon in the ConfirmationCorner 22 Double-click the Plate Layout sketch, and change the 5.8 36 inch dimension to 6 inches Change the 7.244 inch dimension to 7 inches Make sure the model rebuilds, and watch the individual parts update Figure 16. 28 shows... context of an assembly with layout sketches 6 Follow this procedure for four remaining plates, as shown in Figure 16. 24 To summarize the steps again, they are add new part, create sketch, extrude block FIGURE 16. 24 All of the plates controlled by the layout sketches 1 7 8 5 4 3 2 574 6 Chapter 16: Modeling in Context Note Be careful with the plates labeled 5, 6, 7, and 8 There is a clearance gap between... the same rules as the Hole Wizard 9 Place two sketch points at the centers of the circles, as shown in Figure 16. 25 Make sure that the two points are both over the same plate 5 or 6 You cannot cut both plate 5 and 6 in the same Hole Series feature Use the settings shown in Figure 16. 25 FIGURE 16. 25 Placing screw holes through multiple parts in the die Place points for holes Make sure the holes are Counterbored,... Prompt User To Select Document Template n Cross-Reference I discuss the function of Mirror/Insert part in more depth in Chapter 26 n 571 Part III: Working with Assemblies FIGURE 16. 20 The Machine Base Bracket part, ready for mirroring FIGURE 16. 21 The Mirror Part PropertyManager 16 Notice that the new part is indeed a mirrored copy of the original You can see that the “MADE IN USA” text on the bottom is... remove in-context sketch relations is by using the Display/Delete Relations tool You can sort the relations by selecting the Defined in Context option, as shown in Figure 16. 14 FIGURE 16. 14 Sorting sketch relations by type 560 Chapter 16: Modeling in Context If you are considering using the Break Relations tool, then you should either reconsider and use Lock Relations instead or simply remove all the in-context... Front plane, and convert the four edges of the holes, as shown in Figure 16. 18 569 Part III: Working with Assemblies FIGURE 16. 18 Creating holes in-context 13 Cut the holes using the Through All setting Again, be aware of the direction of the cuts Toggle out of Edit Component mode and press Ctrl+S to save the assembly Figure 16. 19 shows the finished assembly 14 Open the Machine Base Bracket part in... window by selecting Open Part from the RMB menu The part is shown in Figure 16. 20 15 Select the Front plane and choose Insert ➪ Mirror Part This creates a new part and opens a new PropertyManager interface, as shown in Figure 16. 21 In this case, select Solid bodies and click OK 570 Chapter 16: Modeling in Context FIGURE 16. 19 The assembly as of Step 13 Note Notice that I used the Insert ➪ Mirror Part... Edit Component mode using the confirmation corner and save the tutorial assembly 7 Now open the file named Chapter 16 Tutorial Machine Assembly.sldasm Notice that the Table Top part in this assembly is using the Wireframe display state, which is assigned in the Display pane 568 Chapter 16: Modeling in Context 8 Right-click the part and select Edit Part from the list, or select the part and click the... demonstrated in an earlier chapter This also means that any in-context references will not update The part will show the out-of-context symbol 558 Chapter 16: Modeling in Context Best Practice For best practice, you should use either the SolidWorks Save As command or SolidWorks Explorer to rename parts and assemblies This applies to all parts and assemblies, but doubly to in-context documents n In-context and . part functions. Figure 16. 6 shows the expanded FeatureManager for a part with an in-context reference in a sketch. External references can have four states, which Figure 16. 6 shows. These are l. creating the reference. n Chapter 16: Modeling in Context 555 FIGURE 16. 11 Using multiple contexts In-context feature Part III: Working with Assemblies 5 56 FIGURE 16. 12 External References dialog. selecting the Defined in Context option, as shown in Figure 16. 14. FIGURE 16. 14 Sorting sketch relations by type Chapter 16: Modeling in Context 561 If you are considering using the Break Relations tool,