Trouble flowing objects on surface

having trouble wrapping these series of tubes round the top profile, spacing turns out incorrect and objects become distorted.
trying to spilt the tubes using the surfaces, to end up with a ring, where the tubes match the spacing and shape when flat.
have tried flow along surface to no avail, is there another technique that will work?
any help is appreciated.

mcneal ring1.3dm (2.6 MB)

Hello - I think you want the ‘Rigid=Yes’ setting in FlowAlongSrf.

-Pascal

Hello - I’d make sure to arrange the outers surface, assuming that is the target, with U and V and Normal matching your base surface (Dir command).

then pick on corresponding locations:

-Pascal