Your object has a few kinks / imperfections. It’s not symmetric. To be able to fillet and maybe other things that follow, I think you’d benefit from reconstructing the object from scratch, on the origin.
I used sections and split parts of your object and the BlendSrf command set to curvature. 1 on the top surface and 0.4 on the perimeter in the XY mid plane.
Ok, even then I’d suggest to create just one of the two objects. It needs to be closed before you copy / mirror and boolean union the two objects. Then fillet.
Hey @sach A one step process is probably not going to work for this model.
you may want to review the pipe trim trick. It’s often the answer for fillets that won’t do what you expect due to some underlying geometry issue, and offers a lot more finate control than do fillets.
Thanks @theoutside yes, I’ve used this trick also (for years). I was really wondering if this simple scenario for automatic filleting will work in one go in rhino 8….
Cool, It’s a good one that a lot of folks don’t know.
Sadly, what you say is simple is actually not… I’d have to point you to the math folks for a more intelligent answer, but scenarios like this are problematic for surfacing on a number of levels. I’m not a math guy so I’m not even going to venture an attempt other than to say what appears simple here as drawn isn’t actually very simple. BUT… if you’d permit me to do so, I’d love to share this model with the math folks to spark a discussion about how we can do this better.