Body Finish & Rough Centerline Toolpaths

FYI: After the design of an edge element is complete, we normally lock that layer.

As we will be using a 1/2" DIA downcut spiral router bit to cut out the body, the offset value will be the cutter's radius or 0.250". Push that new object to Layer 0 (or your favorite "working layer" and then lock the body edge layer.

ETSU's Design Standards & Best Practices for CADD/CAM/CNC

Now... Where to curl on and curl off?

As (a) the neck pocket and "horns" are important elements of the body and (b) the direction of the cutter will be counterclockwise, an excellent place to begin and end each pass would be the "waist" on the lower (right) side of the body. In fact, we have a natural "fly off" if we curl in prior to the lower horn geometry right at the Ogee point.

Turn off the visibility of the CPT_0500-Body-Rough layer

Draw a line snapping to the center of the "waist" arc and the adjoining lower horn arc.

Zoom in on the area as shown above. The line should pass through the Ogee point of the toolpath. If not, fix the edge geometry then recreate the two toolpaths.

Create a circle somewhere on the center-to-center line with a radius of, say, 0.250".

Using Object Snap -> Intersection, move that circle from the appropriate intersection of the circle and line to the intersection of the toolpath and the line.

Select the body edge and the curl on circle then use the Modify -> Trim command to trim the line as shown above.

Rotate the line down to where it intersects the toolplath before the curl on (nominally as shown above).

Select all three objects and then activate the Modify -> Trim command to remove (1) the unnecessary "back side" of the curl on arc and (2) stop the body polyline short.

Use the Modify -> Join command to create a single curl on and body tool path.

Use the Modify -> Extend command to "fly" the waist arc through the ogee point and off the body.

Now we are set up to repeat, more or less, the process for the roughing pass.

Use the Draw -> Circle -> 2 Point command to Snap -> End to the (finish pass') curl in point and then Snap -> Intersection to the center-to-center line and the toolpath.

... pivoting around the finish pass' curl in point

Trim off the "back side" of the curl on arc and, once again, cut short the body rough polyline.

and use the Modify -> Join command to make the curl on and Body Rough polyline one continuous polyline.

swing the line until it intersects the Body-Finish toolpath about halfway between the rough and finish toolpaths. Select the line and use the Modify -> Extend command to fly the rough toolpath through the Ogee point a little bit.

Just like a golf or baseball/softball swing, it's all about the #FollowThrough

and trim off the excess of the Body-Finish tooolpath.

Nice.