Rotating family to curve

Hey guys, im having trouble rotating these families to the curve…
I have already tried to follow some of the treads about the subject, but i was out of luck :frowning:

I uploaded the scipt aswell, together with the Helix… If anyone can give me a solution and or a lesson then i would be a happy man :slight_smile: Thx in advantage and mad love for the Dynamo brains out there :slight_smile:

Helix.rfa (2.2 MB)
Helix mullions placing.dyn (475.5 KB)

It is unlikely that someone will give you a complete solution.

But as a start, you probably want to

  • calculate the direction of the curve (or normal of the arc) in the xy plane at each point
  • then rotate each family instance by that angle

alternatively, use an adaptive family where the placement points are determined by your curve geometry


@Phanse17, oh, I’ve got a working solution for this :grinning:
I’ve already made a custom node to deal with such rotation problems, so there’s no need to reinvent the bycicle. You can either install my package (, or download that single ‘Element.GetRotation’ node and place it in the same folder with your Dynamo graph (see attachments).

This is how your helix looks like after some modifications to the graph (also see attachments):

Hope this helps.

Element.GetRotation.dyf (6.7 KB)

Helix mullions placing ( (165.2 KB)


Zhukoven, you are the MAN! Thx a ton… I wondered if anyone dident do a custom node for this job :slight_smile:

That was exactly what i needed :slight_smile:

I know, but still was hoping someone with the same problem, had a soltuion so i dident have to put in hours for something that where already done :slight_smile:

But thx for leading me on the way tough…

:point_up: What does this mean exactly?

I received a complete solution for a very similar problem a while back.