Datasheet

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Chapter 1: Introducing SolidWorks
Best Practice
It is considered best practice to fully define all sketches. However, there are times when this is not practical.
When you create freeform shapes, generally by using splines, these shapes cannot easily be fully defined, and even
if they are fully defined, the extra dimensions are usually meaningless, because it is impractical to dimension
splines on manufacturing drawings.
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FIGURE 1.25
The fully defined sketch cannot be dragged, and there are no degrees of freedom.
Parametric relations within a sketch control how the sketch reacts to changes from dimensions or
relations within the sketch or by some other factor from outside the sketch. Other factors can also
drive the sketch, such as equations, other model geometry that is external to the sketch, and even
geometry from another part in an assembly, as you shall see later.
Understanding Design Intent
Design Intent is a phrase that you will hear often among SolidWorks users. I like to think of it as
“design for change.” Design Intent means that when you put the parametric sketch relations together
with the feature intelligence, you can build models that react to change in predictable ways. This
gives you a great deal of control over changes.
An example of Design Intent could be a statement that describes general aspects that help define
the design of a part, such as “This part is symmetrical, with holes that line up with Part A and thick
enough to be flush with Part B.” From this description, and the surrounding parts, it is possible to
re-create the part in such a way that if Part A or Part B changes, the part being described updates to
match.
Some types of changes can cause features to fail or sketch relations to conflict. In most situations,
SolidWorks has ample tools for troubleshooting and editing that you can use to repair or change the
model. In these situations, it is often the Design Intent itself that is changing.
Best Practice
When editing or repairing relations, it is considered best practice to edit rather than delete. Deleting often causes
additional problems farther down the tree. Many users find it tempting to delete anything that has an error on it.
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