Corner curves on tapered extrude from Ilustrator paths

Hi I am trying to do tapered extrudes on some curves I imported from Adobe illustrator.

I used the Extrude Planar Curve (ExtrudeCrvTapered) command with a draft angle of 25 and checked the create solid check box.

Many of the resulting solids have hard edges for the rendered geometry but their wireframes look correct.

Does anyone know what is happening here and how this can be fixed? Do I have to rebuild the curves I imported from illustrator?

I am using Rhino for Mac on a 2014 MacBook Pro.

I am also looking for tips on the best way to build this sort of complex 3D texture. I want to save time and not have to extrude each individual curve by running the Rebuild command on each problematic curve. (I have been through this.)

So what is the best way to do a tapered extrude on multiple curves of different sizes?

After the extrusion I also need to do a Fillet Edge on the outer edge of every top surface. I have ran into issues with this also. Some of the smaller “lizard scales” in the texture cause problems for the Fillet Edge command when the fillet radius is set to a “larger” value.

Is there a way to calculate the largest fillet radius that can be used on a curve or a group of curves?

Thanks for the help.

Best regards,


Hi Leo,

Can you post an example file?

Thank you.

This looks like your mesh settings - the wireframe looks OK in the bottom picture. Try setting your display mesh (Settings>Mesh) to Smooth and slower or Custom… Some of the custom settings will be object-size dependent.

Here is more info on meshing. (applies to both Mac and win Rhino)


textura colar.3dm (17.5 MB)

Thank you Helvetosaur that fixed it.