About Toolpaths

A toolpath is a series of movements that the cutting tool follows as it removes material from the model.

Toolpaths are created in RhinoCAM using CAD geometry. There are a variety of different types of toolpaths available, those listed below are used within RhinoCAM and intended for use in milling on the K2 and Forest Scientific Routers.With the correct CAD geometry a combination of the toolpaths below will result in an efficiently milled and finished looking model. In some cases contour toolpaths may also be desired, such as in cutting out an irregularly shaped model from the stock or in creating texture on terrain. Drill toolpaths may also be desired for different texture.

 

Rough Parallel

Removes bulk of material from all surfaces.

The rough parallel toolpath moves the tool in equally spaced parallel passes in the XY plane across the surface. Like all rough toolpaths, it cuts the surface in several Z steps. Rough toolpaths are done with coarse tools and settings in order to remove material before cutting a finish pass with finer settings.

This example shows a rough parallel pass, which is easy to set up but has limitations. It works for blue foam but may not be suitable for harder materials since it may leave too much material behind in some places for the finish tool to cut. Other types of roughing passes are available.

 

Surface Finish Contour

The surface contour toolpath works much like a topographic map, cutting along a series of paths at incremental heights (stepdowns). As a surface becomes more steep the paths get closer together; as a surface becomes more shallow, the paths are spaced farther apart. It is generally unsuitable for clearing material from a horizontal surface, but is excellent for removing material from vertical or very steep surfaces prior to other finish toolpaths.

This is different from the contour toolpath.

 

Surface Finish Constant Scallop

The constant scallop height toolpath moves the tool over the surface in a spiral motion, from the inside-out or the outside-in. The stepover is a fixed amount, but it is calculated parallel to the surface at the location being milled (rather than in the XY plane as with the parallel toolpath. It will make small pockets in some places, if necessary.

This is an excellent toolpath for rolling terrain. It gives a very uniform, consistent result on all surfaces when used with a ball endmill. Use with one large blanket terrain surface with smaller road surfaces below.