Fillet not Solid in STL

My trouble with the hub and fillets seem to be consistent & it builds no errors looks solid in Rhino, selected the surface in the first shot it’s really twisted & took careful work to have it fillet in one pass no chaining.

With a single surface and hub I offset both at one time to 1.3mm & trim, then do a variable fillet, chamfer also works @ 0.35mm that looks fine no errors but isn’t solid, it’s a mesh in other tools.

So now I need quick ideas on what may work, the rest are edge fillets, deadline is tomorrow & thought I was OK hadn’t checked as STL for a while & saw black so checked in FreeCAD same thing.

It’s the basic fillet against the hub and goes in one piece that isn’t solid, haven’t tried every combo of settings so could use advice there, my thought is I’m missing a step if not the wrong settings.


… in MeshLab:

Hi Tom - As always, it’s best to post the surfaces you’re dealing with, and the desired fillet radius, in this case.



Hi Pascal, it’s NDA stuff or I’d post the file & did post a radius of 0.35mm between two 1.3mm thick solids all curves, the two are almost normal for the entire length, spent time on that.

It’s a propeller and hub, attaching the wing to that. It fillets instantly at that diameter the whole way no errors and displays as a solid in Rhino, only a variable fillet/chamfer works.

This shot shows the shape of the boundary before a fillet, it makes this fine I have to taper the trailing edge down to 0.1mm from 0,35mm on the right near the finish & flush with the top of the barrel at that radius, wish I could post the file …

thx, just back from a mtg…

To put something to split on found I couldn’t split on iso’s so put in a tiny triangular piece same sizes, extruded it expecting the fillet to stop there.

Nope, it still did the whole fillet but it didn’t change direction !!! … so cool, luv Rhino it chugged on by and by some miracle that prevented the switch, deleted the piece and no space there.

And, did MeshLab it’s valid STL, no black in lattice … it’s a fine fillet on the most recent wing…

Sharing the joy … :yum:


Tom, you can send confidential files to


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