Help! A failed Donut loft

Hello there!

Very new to grasshopper and i’m wracking my brains over how loft are very inconsistent with more complex surfaces…failed%20donut

I’m trying to make a loft off catenary arcs arrayed on two circles alternated in height as variables. But it seem there is a few values of the arcs randomly flipped for unknown reasons to me!

Advice and help would be much appreciated on where to go from here!

Donuttt (36.9 KB)

in your loft options, try setting the “Adjust seams” option to True.


Donuttt (38.2 KB)

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All you need is a little seam adjustment like @chanley suggests.

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I thought that only applies to closed curves? This requires the flipping of some curve directions. Sadly they all radiate so you cannot use a single guide curve to perform the flipping.

You may have to create a guide for every catenary, or split the list into thise sections with start points closer to the centre and only flip those ones.

  • End Points
  • Distance
  • Smaller Than
  • Sift
  • Flip Curve
  • Combine
  • Loft

You may also consider rebuilding the catenaries so they are no longer polylines.

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I thought that only applies to closed curves?

It works on open as well it seems.

Many thanks for the indepth direction to the nature of catenary!

Thank you so much! :slight_smile:

i feel like an idiot… i tried doing this earlier in the day and it did not work hmm… that was on rhino 5. Rhino 6 seems to work fine or i just missed it!