User Manual

UnDerstanDIng ParametrIc DesIgn

Using the Part in an Assembly

Just as well-constructed parts start with well-constructed sketches, well-constructed assemblies

start with well-constructed parts. Once the part model is built up from the features you create,

you can use it in an assembly of other parts created in the same manner. You can copy the part

to create multiple instances of the same part, and you can copy the part ﬁle to create variations

of the original part. To assemble parts, you create geometric relationships called assembly con-

straints deﬁning how the parts go together. The constraints are parameters that can be deﬁned

and revised by you at any time in the design process, as well. Part models can be arranged into

small assemblies and placed into larger assemblies to create a fully realized subassembly struc-

ture that matches the way your design will be built on the shop ﬂoor. Figure 1.4 shows the part

model from the previous illustrations placed multiple times in a subassembly, and then that sub-

assembly placed in a top-level assembly.

Making Changes

Parametric design is the process of creating parameter-based sketches in order to deﬁne parameter-

based features, which are used to construct a parameter-driven part. Once parts are built, they are

then used in assemblies, which also employ parameters to deﬁne the offsets and mating relation-

ships between assembled parts. Designing with the use of parameters allows you to make edits

quickly and lends itself to creating product conﬁgurations, where parameter values are changed to

create variations of a basic design.

Of course, as with building anything, there are general rules and best practices to be learned

and followed to prevent your work from “falling apart.” For instance, what if the pivot link used

in the previous examples were to incur a design change that made one leg of the link longer?

Figure 1.3

Adding features to

complete the part

model

Figure 1.4

A subassembly and

an assembly model

using the part

model

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