Unroll & FlowAlong Surface Deformation

Hi everyone,

I can`t solve this problem with UnrollSurface and FlowAlong.
The curve from which the surface was created was rebuilt and FitCrv command applied.

Rebuild Curve


Hello - it is very hard to know what you are asking about without an example file - please export all the relevant objects to a new file and post it here, or send to tech@mcneel.com, with a link back to this topic in your comments.


Forum File.rar (10.4 MB)

Good Morning Pascal,

Please see attached file above. I will send this fine directly to the e-mail stated in your reply.

Hi Robert - I would not flow this, I’d build it in place, I think.

Forum File_maybe.3dm (5.8 MB)

(Green objects are extrusions, the white, Sweep1.)


Hi Pascal,

Any chance of sending the file in the Rhino 6?

Hi Robert -

Here’s that file in the Rhino 6 format.
Forum File_maybe-RH6.3dm (2.1 MB)

Note that there is a Rhino file converter that you can download here:

Thanks, Wim,

Converter installed. We never needed one as we had R5 & R6 installed. We are catching up with R7.

Hi Pascal,

I understand why are you saying that it would be better to build it in place. We sometimes do. In most of our cases, we need to have control over several components like spindles, glass panels, and other balustrade sections. FlowAlongSrf helps us line up, move and control all modeled groups into position. This is very important when creating manufacturing drawings or exporting to CNC file format.
That’s why we need to create a perfect surface without any wobbly edges. Rebuild & FitCrv does not always produce good results for some reason as it deforms or explodes the surface into sections.

I would be very grateful for any trick that would solve this irritating issue.

Hi Robert - in that case I would build the object with simple, more exact, surfaces rather than rely on a sweep one to do it all.

Forum File_maybe2.3dm (5.1 MB)