PolarPattern with Z-axis shift depending on the function of angle

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JackkDBA
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PolarPattern with Z-axis shift depending on the function of angle

Post by JackkDBA »

Hi All!
I'd like to make 20 holes in a cylinder. The main problem is that the holes must be shifted in Z-axis using sinus function like this:
- hole number 1: shift = sin(0 * 360/20) * shift_amplitude = sin(0deg) * shift_amplitude
- hole number 2: shift = sin(1 * 360/20) * shift_amplitude = sin(18deg) * shift_amplitude
- ...
- hole number N: shift = sin((N-1) * 360/20) * shift_amplitude

How to make such PolarPattern?

Best regards,
Jacek
test1.FCStd
(239.54 KiB) Downloaded 15 times
Zaznaczenie_001.jpg
Zaznaczenie_001.jpg (145.62 KiB) Viewed 991 times
Last edited by JackkDBA on Wed Nov 30, 2022 10:52 am, edited 2 times in total.
Best regards,
Jacek
chrisb
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Re: PolarPattern with Z-axis shift depending on the angle

Post by chrisb »

PolarPattern cannot do this. Have a look at Draft PolarArray if it fits your needs. It can do Z offsets.
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JackkDBA
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Re: PolarPattern with Z-axis shift depending on the angle

Post by JackkDBA »

Thank you for the answer, chrisb.
Unfortunately, I can't find PolarArray tool. May you direct me, please?
Best regards,
Jacek
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papyblaise
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Re: PolarPattern with Z-axis shift depending on the angle

Post by papyblaise »

it's that :?:
Attachments
hole helix.JPG
hole helix.JPG (29.83 KiB) Viewed 948 times
hole helix.FCStd
(138.74 KiB) Downloaded 19 times
chrisb
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Re: PolarPattern with Z-axis shift depending on the angle

Post by chrisb »

JackkDBA wrote: Tue Nov 29, 2022 7:57 am Unfortunately, I can't find PolarArray tool. May you direct me, please?
Draft PolarArray
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drmacro
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Re: PolarPattern with Z-axis shift depending on the angle

Post by drmacro »

This is also possible with Lattice2 workbench.

https://youtu.be/cjBBse52Z5s
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JackkDBA
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Re: PolarPattern with Z-axis shift depending on the angle

Post by JackkDBA »

drmarco, thanks for the answer.
However, how may I reference current angle to make the position dependent on it?
Best regards,
Jacek
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JackkDBA
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Re: PolarPattern with Z-axis shift depending on the angle

Post by JackkDBA »

papyblaise wrote: Tue Nov 29, 2022 8:19 am it's that :?:
Thanks! It looks very nice. I will take a look :)
Best regards,
Jacek
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JackkDBA
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Re: PolarPattern with Z-axis shift depending on the angle

Post by JackkDBA »

papyblaise wrote: Tue Nov 29, 2022 8:19 am it's that :?:
Unfortunately, the holes are placed linearly, not in positions pointed by the sinus function. Any idea, how to fix it?
Best regards,
Jacek
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papyblaise
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Re: PolarPattern with Z-axis shift depending on the angle

Post by papyblaise »

you need a powerful counter to calculate Z = Z Total /Number of Holes :!:
Attachments
hole helix Z.JPG
hole helix Z.JPG (59.08 KiB) Viewed 698 times
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