Section in a Polar array

Rhino
1

Hi all

I am trying to make sections on this Mobius and the sections to be in a polar array , 60 sections. Is there a command for Section in polar array? I am trying to make the sections follow the shape of the Mobius as it goes around. I did a section in Polar Array but it does not follow the shape, it just multiply around without pivoting to follow the shape.

Thanks for your help.

Mobius.3dm (2.6 MB)

2

Hi Marcel,

I am unclear what you are seeking here. The centreline of your mobius is a planar circle. If you draw lines perpendicular from the centreline, they will lie on vertical planes. I sense that you do not want that.

Are you hoping for planes that are perpendicular to the centrelines of individual faces, as here?

image
image1373×868 95.4 KB

Unfortunately curves perpendicular to each mobius face do not lie in a plane - they spiral around the mobius:

image
image1373×868 117 KB

If instead you take a simple vertical section and skew it to suit one face at a particular point, it doesn’t suit the other three faces and becomes unsuitable to the original face as you progress around the form.

You can’t do better than this:

image
image1373×868 120 KB

Mobius 001.3dm (1.8 MB)

(This is created by making a polar array of planar surfaces and either using _IntersectTwoSets between the array and the mobius to create planar curves or using the mobius to trim the planes to create aligned surfaces.)

Regards
Jeremy

3

Hi Jeremy

Thank you for that! Starting with planar SRF is the key, I have never used -Intersect two set before, I have used -Intersect object many time but never this one. . Much appreciated, thank you again. Great help.