I'm making some decent progress on the model truck project, proofed a good portion of the program, and just working on the finishing toolpaths.
I ran into an interesting and complex problem that took quite a while to get my head around. There's a spot at the front fender of the vehicle that's got two 3D surfaces on two different planes meeting together at a 45deg angle, and I was working through how to machine that with a single contour pass. The problem is that Fusion360 only allows you to select line segments in the 2D contour toolpath, but you're only able to work with a single plane, and so can't have the contour follow a surface that curves in the z-axis.
After discussing it with my boss, he explained how to draw out the spline and use a trace toolpath to get that curve. Normally I wouldn't say I like creating manual sketch geometry for my CAM programs as they are very messy, and you can't change the original 3D model without throwing it off. But in this sencario, there isn't a better option.
The biggest complex problem was drawing this 3D line floating in space and figuring out how to have it flow with the edge of the tool just touching the surface and not gouging it. I couldn't just project a line from the existing curve, as the tool would follow the centerline of the path and not the edge so that the endmill would run fine while at the flat edge, then as it curved downward, the endmill would start cutting into the model. I drew up a quick sketch of what it would look like from a top-down view.
It turns out, creating this spline was much easier than you'd think. I was able to copy the model's arc and just shifted it to the side by half the tool diameter. Thus creating a delayed path that the endmill could follow.
Once I had the difficult 2D arc created, I was able to pull that line into a face and projected the other side geometry onto that surface, and I had my 3D curved arc spline! I did a quick trace toolpath to ensure that it worked like it should and got exactly what I was aiming for!