Silhouette Boundary vs. Curve Edges

[Bill H]

If I use the Silhouette Boundary command to create wireframe geometry of a part's perimeter, curved edges are either a series of small arcs or (worse) a group of lines and arcs.  As examples, the edge of a hole will be created as four (or more) arcs of unequal length.  A simple 90-degree curve will be two lines plus an arc.  The Curve Edges command, on the other hand, creates arcs that accurately reflect the part's geometry.  A continuous arc on the solid model will be a single wireframe arc.  Why do the two methods produce different results?  Is this controlled by a setting?

[JParis]

The biggest difference between silhoutte boundary and create curve on edge, or create curve slice is that sihouette is a projection type creation...it will pick up on VERY slight variances in geometry. You see that reflected in how it sometimes catches corners and even straight geometry if it shares a common edge but at several Z depths...you can try tightening up the tolerance and using Arc fit....even with those however, you might find slightly "less" than perfect geometry.

I typically will not use silhouette boundary for anything beyond a roughing path.....if I need good clean geometry to cut, I'll use Create Curve edge or Create Curve slice..