Logarithmic Spirals/Golden Spirals

Does anyone know how to sketch a logarithmic/golden spiral in Shapr3D? I’ve checked the online documentation and searched the forums and cannot find anything. Thoughts?
Be well. Stay safe.

I would think you would need scripting capabilities for that.

Hi. I use the 90 degree approximation of the “golden spiral” in handrail making.

Most people drawing these use an approximation. But as @Oregonerd says, the genuine version would at least require a formula input of some kind.

There have been a few posts on the subject in the past, but mostly using a 180° approximation.

Let me know if you’re needing help with the 90° version.


Guidance for drawing the 90 degree approximation would be incredibly welcome. Thank you!

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Start with a box 1 unit (inch, cm, mi, etc). Lock it’s sides and location make a box 1.61 times that next to and lock it also. Repeat that multiple times. Then draw arcs in the appropriate corners of each box whose radius is = to the side of that box….

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1̶.̶6̶1̶ ̶i̶s̶n̶’̶t̶ ̶p̶e̶r̶f̶e̶c̶t̶ ̶b̶u̶t̶ ̶c̶l̶o̶s̶e̶ ̶e̶n̶o̶u̶g̶h̶?̶ ̶Y̶o̶u̶ ̶w̶i̶l̶l̶ ̶n̶o̶t̶i̶c̶e̶ ̶s̶o̶m̶e̶ ̶a̶n̶n̶o̶m̶o̶l̶i̶e̶s̶
Try 1.618 as your multiplier.

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Thank you for the link and guidance! You all are the best!

I think my solution is closer to the Fibonacci, less Golden ratio.

Helping you was a fun rabbit hole for me! :slightly_smiling_face:

This was quite fun for me as well! Thank you so very much!