Part II: Building Intelligence into Your Parts
When SolidWorks puts the child feature at the top, it is, in effect, turning the relationship upside
down. In the SolidWorks FeatureManager, the earlier point in history is at the top of the tree, but
the children are listed before than the parents. The SolidWorks method stresses the importance of
solid features over other types of sketch or curve features.For example, you create an extrude from a sketch, and, therefore, the sketch exists before the
extrude in the FeatureManager. However, when you create the extrude, SolidWorks places the
sketch underneath the extrude. This restructuring can become more apparent when a sketch (for
example, Sketch1) is created early in the part history, and then not used to create a feature (for
example, Extrude5) until much later. If you roll down the FeatureManager feature by feature, you
arrive at a point at the end of the design tree where Extrude5 appears and Sketch1 suddenly moves
from its location at the top of the tree to under Extrude5 at the bottom of the tree.This scenario may cause a situation where many sketches and other features that are created
between Sketch1 and Extrude5 are dependent on Sketch1, but where Sketch1 suddenly appears
after all these other features. This can be difficult to understand, but is key to effectively editing
parts, especially parts that someone else created.The main point here is that SolidWorks displays many relationships upside down. You need to
understand how to navigate and manage these history-bound relationships.One way to get around difficulties in understanding the chronological order of features when com-
pared against the relationship order of features is to roll back a model tree item by item. This can
help you sort through the issues. Also remember that from SolidWorks’s point of view, the solid
feature is the most important item in the tree and is what the rest of the items in the tree support.
SolidWorks has made the solid features easily visible and accessible in the tree.Rolling back features with multiple parents
Take an example such as a loft with guide curves. If you create the guide curves first, and then you
create the loft profiles by referencing the guide curves, the loft automatically reorders these
sketches when they display under the loft feature such that the profiles are listed in the order in
which they were selected, followed by the guide curves in the order in which they were selected.
This is shown in Figure 11.3. This restructuring can be confusing if you want to go back and edit
any of the relationships between the sketches. You can find this example on the CD-ROM with the
filename Chapter 11 Loftwgc.sldprt.Note
In this example, the two guide curves were created as part of a single sketch, and the SelectionManager was
used to select them as individual open curves. This is why the Guide Curves sketch is represented with the
contour symbol rather than a regular sketch symbol. n