Offset on Surface Fail?

Anyone know why my offset on surface keeps failing?offsetfail.3dm (3.0 MB)

it does work in the latest wip, maybe update :wink:

Really? Strange… I do have the trial version of the mac rhino

Are you trying to offset the surface? Or are you trying to offset a curve on the surface?

How large is the offset, and in which direction?

I’m trying to offset the curve onto the surface. About 1.5cm upwards from the edge towards the center of the surface.

unfortunately it does not succeed very clean, it partially creates the tangential curves also gapping one edge out so you need a little workaround:

this all is just to get your offset curves so you can keep the initial surface duplicate it and hide for now. then use DupBorder on the existing surface, select the surface again and use rebuild, the following settings worked


it will untrim the whole surface with this setting (probably a bug) so this is where you use the duplicated boarder to retrim it again. OffsetCrvOnSrf works now.

Hi Jaquomatic- I guess that is a tough case with the curve passing right through the singularity of that surface - a reasonable, in this case, workaround might be to simply make a plane at elevation 1 and Intersect.


How exactly do you make the plane at elevation 1 and Intersect? I’m a beginner.

Thanks, but why does rebuilding the surface allow for the offset to work?

The easiest way would probably be to make the plane on the CPlane and then move it up one unit.
That or typing 0,0,1 when the plane command asks for the first point.

I’m actually still a little confused. The C-Plane for the perspective view or any plane? And how do I do that?

OH! Ok, so that rebuilt surface with those dimensions is the original shape I was working with before I split the surface. Do you think if I had offset the curve first, before I split the surface, the offset on surface would’ve worked? It’s interesting that it won’t work on this segmented surface.

The World XY CPlane - so either in perspective or top view.

actually you can skip that part with rebuilding it, untriming the whole surface and offsetting the duplicated curves already works.