Curves workbench

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Chris_G
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Re: Curves workbench

Post by Chris_G »

drmacro wrote: Tue Nov 08, 2022 4:49 pm Attempting a sweep on 2 rails with the green edges:
sweep on 2 rails is really old crap.
I would suggest to try Gordon first.
But, indeed, both tools fail at choosing the right circle arc.
By setting the Tolerance of the Freehand_BSplines at 1e-7, it is also possible to use Surface->Fill.
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Re: Curves workbench

Post by drmacro »

Chris_G wrote: Wed Nov 09, 2022 5:52 pm ...
sweep on 2 rails is really old crap.
I would suggest to try Gordon first.
Yes I knew sw2p is old.

I tried it as a fallback after Gordon failed...
But, indeed, both tools fail at choosing the right circle arc.
By setting the Tolerance of the Freehand_BSplines at 1e-7, it is also possible to use Surface->Fill.
The tolerance setting seems to work. I'll proceed with the rest and see if it continues to be the magic sauce.

Thanks!!
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drmacro
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Re: Curves workbench

Post by drmacro »

I was able to complete the surfaces and convert to para solid.

But, Surface and Surface004 fail geo check. Any tips on getting them corrected?
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Vincent B
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Re: Curves workbench

Post by Vincent B »

you have forgotten a surface for the solid. ;)
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Re: Curves workbench

Post by drmacro »

Vincent B wrote: Thu Nov 10, 2022 5:37 am you have forgotten a surface for the solid. ;)
The surfaces I mentioned fail geo check on their own...and are the same errors (same face/edge) on them or the solid.
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Re: Curves workbench

Post by bleber »

How to make periodic regular b-spline like the screenshot.
Screenshot_20221111_233302.png
Screenshot_20221111_233302.png (30.35 KiB) Viewed 1003 times
I can build the basic shape but the end and the star joint is not regular as other points.
b-spline curves workbench
Screenshot_20221112_000742-1.png
Screenshot_20221112_000742-1.png (17.09 KiB) Viewed 1003 times
b-spline draft workbench
Screenshot_20221111_233212.png
Screenshot_20221111_233212.png (9.23 KiB) Viewed 1003 times
chrisb
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Re: Curves workbench

Post by chrisb »

bleber wrote: Fri Nov 11, 2022 11:10 pm How to make periodic regular b-spline like the screenshot.
Use addon Parametric Curve FP or 3D Parametric Curve.
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hammax
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Re: Curves workbench

Post by hammax »

... I also found this problem some time ago, but there is no "wiki"
about handling periodic and tangency at the closure ???

pBSpl.PNG
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Chris_G
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Re: Curves workbench

Post by Chris_G »

bleber wrote: Fri Nov 11, 2022 11:10 pm How to make periodic regular b-spline like the screenshot.
I can build the basic shape but the end and the star joint is not regular as other points.
Unfortunately, OpenCascade doesn't seem to support all types of periodic curve interpolations.
I looked for possible solutions this morning, but without success.
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Re: Curves workbench

Post by bleber »

The problem to be a wrong tangency in the junction knot.
Screenshot_2022-11-12-12-26-35-52_8218ad734a8157e87572f0f6e2674adf.jpg
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