It’s been quiet here for a little while but work has quietly been progressing on the arc fitting code. I got feedback from a number of users who demonstrated cases where my code failed to produce good results. I would call my first release of the code a “one-pass” arc fitter. My new code is taking the output from that code and trying several optimizations on the toolpath to make it as smooth as possible. I ran my first real toolpath today using the code and it seemed to run really well. The mill seemed to handle the arcs much better than the linear paths. The testing was very non-scientific because my mill just got a control upgrade because of a blown VFD; it might also have been the corresponding upgrade from Mach 2 to Mach 3. (A word of warning to Tormach users- if you have the analog VFD then you can look forward to a failure like mine when the pots get old and dirty) Testing will continue and I expect a release in a week or so.
One other change is an upgrade in toolpath quality. I tweaked some internal constants to give a better toolpath for a given tolerance value. You may find that you can backoff the tolerance value a little and still get an equally good toolpath in the next release. If you choose to keep your tolerance value then you will see a smoother toolpath if you know where to look but it will take longer to calculate. This will improve the flaws that Gerry found and posted in the forum.