Page 295 - Mastering SolidWorks

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Selecting a SPecialty Feature 267

Figure 8.8
a part created from a
composite curve

Using Split Lines
Split lines are not exactly curves; they are just edges that split faces into multiple faces. Split lines
are used for several purposes, but they are primarily intended to split faces so that draft can be
added. They are also used for creating a broken-out face for a color break or to create an edge for
a hold-line fillet, as discussed in Chapter 7, “Modeling with Primary Features.”
There are some limitations to using split lines. First, they must split a face into at least two
fully enclosed areas. You cannot have a split line with an open-loop sketch where the ends of the
loop are on the face that is to be split; they must either hang off the face to be split or be coinci-
dent with the edges. If you think you need a split line from an open loop, try using a projected
curve instead.
CAUTION a word of caution is needed when using split lines, especially if you plan to add or remove
split lines from an existing model. the split lines should go as far down the tree as possible. Split lines
change the face ids of the faces that they split, and often the edges as well. if you roll back and apply
a split line before existing features, you may have a significant number of feature references to fix.
Similarly, if you remove a split line that already has several dependent features, many other features
may also be deleted or simply lose their references.

Using the Equation-Driven Curve
An equation-driven curve is not really a curve feature; it is a sketch entity. It specifies a spline
inside a 2D sketch with an actual equation. Even though this is a spline-based sketch entity, it can
be controlled only through the equation and not by using spline controls. This feature is covered
in more detail in Chapter 3, “Working with Sketches and Reference Geometry,” with other
sketch entities.

Selecting a Specialty Feature
SolidWorks contains several specialty features that perform tasks that you will use less often than
some of the standard features mentioned in Chapter 7, “Modeling with Primary Features.”
Although you will not use these features as frequently as others, you should still be aware of
them and what they do—you never know when you will need them.