Hi, I am required to round the edge made of pipes seen below in the screenshot. However fillet srf doesnt work and I am not aware other methods. I was wondering if anybody knew the answer to this problem. Much appreciated and thanks in advance.
Thank you for your report, could you give it a try with Pipe + Split + BlendSrf ?
I have logged this issue with our development engineers.
RH-89892 FilletEdge: Fillet on pipe edges failed
@jessesn
In this case, without further efforts, the transition becomes thicker than the pipes:
FilletSrf does the job.
Filleted pipes.3dm (2.7 MB)
Becomes a bit better, but not right.
Using _Boxedit, you can see that immediately.
Also, the shape is far from expected.
Some helper curves + NetworkSrf makes an acceptable result.
2025-10-13_Pipe_Fillet.3dm (1.3 MB)
V9 WIP is not any better in this situation, I hoped for FillSrf or FilletSrf.
Iâd expect such a simple situation fillet should work.
Cheers, I appreciate the answer.
Yes, but you have to be patient:
Patient? Worked for me instantly.
In V8 macOS, there is no âContinue across facesâ. In fact, I get the same result with V7 macOS. FilletSrf has always been rock solid.
my prefered solution
Pipe_corner_rounded_tomp.3dm (3.5 MB)
⊠not a fillet but the edges are roundedâŠ
If you aim for the perfect degree 2 pipes and a clean true radius round blend between the pipes, this is how I would do it. Check the macro in the video description, same as the one posted at the bottom of this post:
This method also works with non-round profiles, as long as they are the same shape that connects together.
In case that the pipes are already existing and you donât have their centerline, the following scripts and macro could be used to make that manually (the same macro is also used in the above method):
ExtractCenterline.py (6.5 KB)
ExtractPipeCL.py (4.0 KB)
Axis from arcs and circles:
! _CPlane _Object _Pause _ProjectOsnap _Toggle Enter _Pause _Line _Vertical 0 _BothSides _Pause _Pause _Cplane _Undo _ProjectOsnap _Toggle Enter
Look at his screenshot. This is the way. FilletSrf does the job well.
It depends on the intent. My approach maintains the diameter of the pipes, which is the most common usage scenario.
Pipe fillet.3dm (694.7 KB)
Well, the OP wants to âround the edgeâ and claimed that âfillet srf doesnt workâ, while it does work as shown above.
Perhaps the âFillet stfâ tool canât produce the expected result. âRoundingâ is a pretty loose term, especially when it comes to pipes where the most natural application is to connect the two straight pipe segments by a round segment that simulates an arc bending. 
Well, the OPâs screenshot shows how the pipes are joined, with a miter joint, ready for welding.