Help with failing FilletEdge

I’m a fairly inexperience Rhino user. I am trying to fillet some edges on my model. Some edges behave well, but I have spend hours already on others.

This is my model:
Fail.3dm (416.5 KB)

I am trying to fillet this edge:

and I get this after EdgeFillet:

Any suggestions on why it is failing and how to fix it?

Are you trying to fillet that entire edge loop or just the segment indicated in your second image? What size fillet are you trying to use? Is it 0.5mm? If so I’ve just put a 0.5mm fillet along that whole edge loop without problem, which slightly surprised me as you have non-tangent segments.

There is no obvious way for a computer to know how to finish the fillet there. Like @MisterB says, continuing the fillet around the loop works…if that is what you’re after.

Try using that fillet result and model the ends of the fillet manually if that is the extent of the fillet you want.

Also, try these websites for hints.

Thanks for that.

The biggest problem had been my reasoning. I tried to fillet the whole loop, but had some issues with that. Then I thought I can isolate the problematic section by filleting just 1 edge at a time. Of cause that created other problems.

I got this fixed in the end by applying the fillet on the whole loop and setting small values for the side sections and bigger values for the middle section.

Thanks for pointing me in the right direction.

I don’t however completely understand MisterB’s comments on the non-tangent segments. So to help me understand that can you please indicate:

  1. Which sections are non-tangent.
  2. How do you know they are non-tangent. To me all the loop’s edges appear to cut the vertical side walls at 90 degrees. Doesn’t that make them tangent?
  3. Why is this a problem when filleting edges?

Conrj, the three edges indicated in the image are non-tangent. In this case the fillet still works but generally fillets works best if the edge loop is tangent continuous. That’s my experience anyway, hopefully a more expert user will chip in to explain why this is the case (if it is indeed the case).

Use the Gcon tool to check continuity. It will tell you if edges are tangent.

Thanks, that makes a lot of sense now.

Will keep that in mind for the next model.