Face Vs Feature patterns for holes

michal_raviv

In the basics tutorials both face and feature patterns are used to create holes. In what cases should I use each option?

Jake_Rosenfeld

Hi @michal_raviv

In general (as of recently), Face pattern and Feature pattern (with the "apply per instance" turned OFF) should do exactly the same thing.  The only difference is that for Face pattern you will select the interior faces or the hole (create selection is a good tool to help make this selection), and for Feature pattern you will select the hole feature itself.

The real difference comes when "apply per instance" is turned ON.  As an example, take this hole feature definition:


Notice that the feature is doing a "Blind" with "Start from sketch plane" turned off.  This feature is telling the system to make 2 inch deep holes measuring two inches from the start of the material, not from the sketch plane.

On the left is a feature pattern with "apply per instance" ON.  On the right is a face pattern:


You'll notice that the feature pattern is patterning the feature itself (it is making four holes that are each 2 inches deep from the start of the material).  The face pattern (which executes the same way as a feature pattern with "apply per instance" turned OFF), is just doing a pattern of the geometry, not a pattern of the feature.

So, if you do not need a pattern that re-executes the feature for each pattern instance, use face pattern or feature pattern with "apply per instance" turned OFF.  This will be fast because it is doing a simple pattern of existing geometry.  If you NEED the pattern to re-execute the feature for each pattern instance (this need should be a rare occurrence), turn "apply per instance" ON.  Generally, this will be a lot slower than leaving it OFF or using face pattern.