Approximating a Spline as a Series of Arcs

You can create a series of arc entities that approximate a Spline according to a specified deviation tolerance.  This allows you to create 2ax Contour or 2ax Pocket toolpaths with arc segments to obtain a better surface finish, faster NC Verify speed, and shorter NC code without having to bother with the Arc Filter.

The procedure is as follows:

1. Set your active color to something different that the color of the spline you wish to approximate.
2. From the main menu, select Create-Arc-FromSpline.
3. Set the dialog box entries as shown below:

Notes:

The number of “Check Points Per Span” tells SURFCAM how many intermediate calculations to make to ensure the arc is valid.  If you increase this number you will get smaller arc segments.

The entire Spline must live in a plane parallel to the active Cview.

The “Fit Area Least Squares" checkbox uses slightly different mathematics; if this box is not checked, SURFCAM uses the Total Least Squares (TLS) method for fitting the arcs along the Spline.