Toolpath selection help

[4Lester (Lester Haury)]

I am trying to find the right tool path strategy for the top half of an airfoil. The geometry is basically 1/4 of an ellipse and the tool is a ball end mill (0.25" or 0.125"). When the tool is transitioning from the horizontal to the vertical I cannot keep the tool on the contour to the vertical. I have contact point boundary on. I can see it is related to the tool not going past the bottom of the wing, but the part is much thinner than the stock to allow the bit to overcut but it does not. in the past I think I used steep and shallow but with personal license it is not there any longer.

Any advice is appreciated.

[Julien (Julien (Carbide 3D))]

@4Lester

but the part is much thinner than the stock to allow the bit to overcut but it does not

When I have this situation, I usually force the toolpath to go deeper that the bottom edge of the part by:

• setting a stop depth to stock/model bottom minus a few mm (negative value in the “offset” field)
• and also adding a radial offset to the selected outer contour (can’t remember to name of the option/menu and I can’t run Fusion right now, but it’s where you tell it the containment boundary for the toolpath, whether the tool should be inside/on/outside the boundary: select outside plus add a positive offset at least half the diameter of the tool)

Last time I had to do that was to cut a half-sphere, letting the cutter go lower than the base, such that the side of the ballnose endmill used for finishing would go down to the base

[4Lester (Lester Haury)]

Thanks, lowering the bottom height did the trick.