Hey,
I've been dipping my toes in Fusion360's CAM lately, given that I finally own a 4-axis machine. However there are certain things that I can't seem to figure out. One of them is that when I make a pocket in a cylinder, with a cylindrical bottom, the paths generated by Fusion are not good for me, as I need very good surface finish on the bottom. The 2D Pocket operation, wrapped on cylinder looks like this:
The parts that are in line with my 4th axis turn out very well, however those perpendicular not so much. There is a cusp showing up (a little ragged) after the endmill. The endmill I'm using is a single flute fi2,5mm. I thought this could be an issue with the spindle not being perfectly perpendicular, but when facing flat surfaces there is only a very slight ridge, barely noticable to the touch. I am also doing a finishing pass with very little axial dept of cut, tried different parameters, no dice.
So I would like to have a path that does not have those perpendicular parts. AFAIK there are no CAM operations for that, so I thought of drawing the path manually and then using 2D contour and wrapping it. What I'm looking for is something like this:
so that I can get most of the bottom the better way and then just do a 2d contour to finish the edges. To create such a path I would like to unwrap the pocket to get something like this on a flat sketch:
which will be done by creating an offset to the inside, then pattern some lines, trim them and get what I want.
How do I go about getting the unwrapped pocket surface? I tried projecting it etc, but the results are no good, since this pocket is more than 180 degrees of the whole cylinder.
I would really appreciate your help in this matter, thanks!
EDIT: Also, the pocket is created like this:
I'm doing split face with that, then offset surface and my pocket is done.
