# Complex Geometry Offset with Consistent gap - Kangaroo?

Hi all,

I am having trouble creating a clean offset of a complex surface.
The base surface is created as a network surface, which I then used Kangaroo to get a nice smooth form

I am now trying to offset the surface inward to have a consistent 600mm gap between the two.

I have got as far as manually creating a second inner surface, which now has a pretty consistent distance when measuring from outside edge to inside edge, although I am having difficulties making that distance consistently 600mm all over.

I have tried dividing both surfaces into the same # of points, draw lines between them, use line SDL to create 600mm lines, rebuild surface from endpoints. The problem with this is I couldnâ€™t get a clean result.

The design intent is to have the inner surface offset inwards (when viewed in plan) and to have the base/stem that runs vertically to be more or less the same as the outer srf.

My hunch is that there might a way with kangaroo?

I have attached the rhino file with the geometry. Any advice would be much appreciated.

OFFSET.3dm (1001.4 KB)

Your surface have some part with curvature radius smaller than 600, how do you expect to have a â€śconsistentâ€ť gap? With creases?

Regardless of surface curvature radius, is it not possible to make the distance between the two surfaces 600mm?

I got close using Line SDL and surface from points, but I was definitely missing a few steps.

No. I think @maje90 meant that if the curvature radius is less than 600mm (as illustrated below = 500 mm) then going inward along the surface normal (the red arrows), the normals cross over, meaning that a surface cannot be built intersecting itself (or whatever that would be called). Like so:

// Rolf

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Thanks @RIL
Maybe I am using the wrong terminology.
What if you think of it as a move of 600mm rather than an offset?

Heres where I have go to by used line SDL and points from SRF.
Still needs to be refined.

Any thoughts?

So you want a correct distance between borders but not on the actual surface?