HI All, I can’t figure out what is wrong with the hawk curve in this file. I can’t seem to extrude it as a closed planar curve. How can I see where there is something that is not joined on the curve? After extruding, I want to fillet the edges.
_CrvStart and _CrvEnd will put a point at the start or end of a curve. If it is open, the start or end will be the open spot, zoom in to look. Also check for overlaps at that point.
Hi, Here’s the file. I tried CrvStart and CrvEnd and they ended up on the same point. I still can’t make a surface from closed planar curves because it says they must be closed and planar. The curve is the one in dark purple.
???rounded corners hawk.3dm (69.1 KB)
Well, as I have often said before… If you need a closed, planar curve to make a surface and it wont…
If you know it’s closed… it must not be planar.
In this case you have a non-planarity of about 0.074mm, looks like the outer wingtips are the most out. You can also see this easily by calling BoundingBox on the curve, if it’s planar and on the Z0 plane, BoundingBox will make a rectangle; if it’s not planar, BoundingBox will make a surface box.
You can also see the non-planarity if you zoom in from Front view.
You can fix your curve by using ProjectToCPlane.
Hi Mitch, Thanks for the help! I have one more question for you. What is the best way to go from my planar curve to an extruded curve of .8mm with filleted edges? I have a very hard time understanding how to fillet something–it never works for me! I know how fillet the curves when they are 2d but when it gets to 3d…
Let me know!
Well, 3D fillets on your object are going to be… problematic. You have a lot of little inside corners and kinked spots, which Rhino’s edge filleter won’t like particularly… plus, even the tiniest fillets are going to be too big to “turn the corner” on some of the tighter bends, some of which are under 0.1mm in radius.
So first you will need to modify your original curve to accommodate the fillets you want - smoothing/eliminating the kink zones and opening up the radii so that your filleted edges will actually fit without self-intersecting…
I’ve marked some of the trouble spots in the file below… But it will take a good bit of work to make this “filletable”.
rch-markup.3dm (51.6 KB)
Thanks. I might just go with bare edges since a client already liked this particular design.