Part III: Working with Assemblies
In some situations, configurations work well with in-context relations. One example of this would
be when an assembly has many configurations used for positioning parts. In this case, use one con-
figuration for the sole purpose of creating in-context relations.In-context with motion
You should make in-context references between parts where there is no relative motion. The parts
themselves can move relative to the rest of the assembly, but they should remain stationary relative
to one another. The parts should also be fully defined to ensure that they will not move; you
should not simply count on avoiding dragging underdefined parts.In some cases, such as an assembly of imported parts, it may make sense to fix parts in bulk rather
than to mate them. When you are using in-context relations, you need to take extra care to ensure
that the parts do not move around. When parts move around, in-context features also move.Obviously, if the motion is around a circular hole and the in-context feature is circular and is not
affected by the rotation of the referenced part, then it makes less difference; however, if there is a
keyway, that may change things. You need to pay attention when combining underdefined parts
and in-context features.Best Practice
For best practice, you should avoid in-context relations between parts when relative motion is allowed
between these parts. n
In-context with multiple instances
Another situation that can cause problems is when multiple instances of an in-context part are
being used in the assembly. In cases like this, you need to be careful and consistent, by always
using the same instance to create the in-context relations. You can do this by putting parts into
folders, or by giving the in-context part a special component color.One trick used by some people is to use one instance of an in-context part for the in-context rela-
tion, and a second instance of the part to allow motion. In-context relations are tied to one specific
instance of a part, regardless of how many of those parts are in the assembly. You might want to
set the driving in-context part aside by putting it in a folder, changing its color, or hiding it.In-context and file management
Understanding what you are doing with file management is imperative when working with parts
that depend on in-context features. Because the references are stored in both the part that is doing
the referencing and the assembly where the reference is created, improperly changing the name of
either document or even the referenced document is bound to cause problems. For example, if you
rename an in-context part using Windows Explorer, then the assembly will not recognize the part,
as I 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.