Ofsetting closed curve fails

I want to offset a closed curve which is an import of a DXF file. But when I do that, I only get several open curves (black in the image) around a part of the green curve which I wanted to offset. How can I get a good offset on this green curve?

The file I was working on is:28.3dm (1.2 MB)

Hi @Hans2,

your larger closed curve is a polyline made from over 7000 line segments. I am afraid, the only way to offset this by a larger distance is by breaking the polyline into multiple sub-polylines and first convert these to smooth curves, then do the offset.

There are some scripts posted here to do the breaking part…


You can use clipper plugin

Or bowerbird plugin

For clipper there is a rhino command

I just installed Clipper in Rhino and it works perfectly. Thanks a lot for this tip.