Flow a twisted shape along a helix joining problem

Rhino
1

Hello,
I am trying to make a mobius coil ring with two coils. I have tried two different ways but I can’t get the join to close.

  1. I created twisted profile curves along a base curve, flowed the profile curves along the target helix, used sweep 1 (with closed sweep checked) with no luck getting a solid.
  2. I extruded a square curve along the base curve, twisted this, then flowed this along the target helix. Still no luck. I’ve attached a screen shot of the problem area. As well as the file.

I really want the twist to only have a 90 degree twist, not the full 360.

Can anyone help me please?

TIA Anna
_ double helix for help.3dm (3.2 MB)

Screenshot 2024-10-01 at 2.17.10 pm
Screenshot 2024-10-01 at 2.17.10 pm1920×1259 74.7 KB

2

Hi @annadavern
Your target curve (the loop) has kinks where the ends meet - on both sides. You can use Gcon to check. Use Match to make sure that they are both at least G1 (tangency) and rejoin them. Redo the Flow operation, Explode and rejoin the result and all should be good.
HTH, Jakob

3

Thanks Jakob, I’ll have a play with those commands as I haven’t used them before, but I just remade the loop and it worked. Thanks again