In some 2D ops like pocketing, there is a cut arc fitting checkbox on the advanced parameters tab. This will force the output to be arcs if the parameters are set correctly.
In principle, for 3D ops, the output will always be line segments, if you want to convert to arcs you need to do the arc fitting in the toolpath editor for each toolpath you generate. Double cick on the toolpath icon in the browser, that opens the editor, there is a button for convert to arcs. There is a dialog with settings.
In actual practice, for 3D ops, I found it very hard to set VM's arc fitting up so that it actually works, so I never bother. Part of this may be due to the fact that a number of VM's 3D routines don't really produce toolpaths smooth enough to be arc fit in one plane, no matter how you set the operation up. Or maybe their arc fitting routines are just poor.
My machine doesn't really need arc fit for 3D stuff, having a high speed control capable of processing large amounts line data quickly. The files are big, but so what... --ch  |