Fillet fail (open brep from closed)

Hi! I am trying to fillet the following brep (must keep the settings: continuity, radius value, metric). The problem is, this fillet creates open brep.

Could someone please take a look? I checked related posts and it seems my brep is among the simple cases (does not have more than three fillet running into each other, so perfect job for gh). I’m wondering what could have gone wrong.

Thanks a lot! (185.3 KB)

This is confusing because, I don’t see any causes of failure mentioned in other posts.


The problem seems to come from this very small edge here.


If you have access to the original Brep, maybe try to move that seam somewhere else…

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Hi magicteddy, thanks for helping me!

Are you talking about this edge here?

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This is where it came from:

I fillet these walls. In this picture, I fillet the top right corner. I can’t get the fillet to end exactly at the opposite side (the bottom side in the picture), so I end up with that tiny edge. Could you recommend some alternatives for situations like this?

Thanks again!

Also, my gh says the result is an open brep (the fillet module doesn’t give errors) because the top face is missing

What is the tolerance of your file ?
I get an invalid Brep with the top face having problems to be trimmed.
Rhino WIP leaves it open indeed, so you can add the remaining face by splitting the untrimmed version of it with the naked edges of the filleted Brep :man_facepalming:

And Merge is as frustrating as ever, but that is a side problem. (191.7 KB)

R7 version with the filtering of invalid faces (192.1 KB)

You could try to fillet the base curve (the wall seems to be an extrusion) instead of the Brep to remove that tiny edge ?

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Thank you for this solution. I get these from some code and, every time the result is different so, I’m trying to figure how a ‘universal’ solution to these. I just realized that the tiny edge can go away if I let the fillets run into each other (see picture)

For filleting the base curve (in this picture a rectangle), gh doesn’t allow curvature, which I need. I will have a bunch of these walls going in different directions (and that aren’t straight), so I need more tryings to figure out how to do these curves in a universal way

remove arcs
Connect Curves (9.5 KB)

I can’t see any of your pictures BTW.

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Just fixed (picture)

Thanks for this very good solution. This is better than the fillet edge actually (the curvature fillet is very pointy, and there’s no indexing for edges)

It must be extremely difficult for McNeel to make Rhino a modern CAD.

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Awwwww maaaan! Even CONFUSion 360 gets ahead on this task!