Boundy vector offset limitation

[SawdustandSmoke]

Hello I have an interesting problem, I am cutting a 3d model that tapers down on two sides and is straight up and down on the other two sides, I must have a boundary vector offset so that the down curving parts will cut properly and not leave any flat areas at the bottom, the problem is that this causes my tapered end mill to cut the flat parts as well making them slightly curved. Is there any way to avoid this???

[TReischl]

Can't cut straight up and down sidewalls with a tapered end mill, the walls will at least have the angle of the bit on them.

Beyond that, not sure what you are describing. You said you had tapers, straight up and down along with curving down?

A vector file or crv3d file would clear those questions up.

[tmerrill]

I have approached this issue 3 different ways depending on the design and project. All three can work but without seeing exactly what your project looks like it is hard to recommend one over the others.

1. You don't need just one machining boundary and can break it up into regions. The region covering the tapered edges would have a boundary vector offset applied, the region covering the straight sides would have no BVO applied. You can combine the toolpaths into one when saving them and since you are using the same bit and haven't had to reset Z-zero the regions should match exactly.

2. Do some vector offsets and node editing to move the boundary vector inwards by the Boundary Vector Offset amount where you don't want the toolpath to cut the vertical edge. The tool will still go beyond the boundary vector in these areas but not go over the edge.

3. Add a simple 3D planar surface, or extend the straight edges farther outwards so the toolpath always keeps the bit on a 3D surface. Then the final 2D profile cutout toolpath will trim to size.

Tim

[SawdustandSmoke]

Thanks for the advice I had not thought of doing it that way, What I have been doing is to draw a vector over that straight areas and cutting on the line to flatten it back out, but that is causing some fuzzing on top that is difficult to sand out.