Loft over multiple sketcher bsplines fails

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microelly2
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Loft over multiple sketcher bsplines fails

Post by microelly2 »

I want to create a loft over some sketches
it is possible to create a loft between two sketches but not over all of them.
there is no error message.
what is the reason?
loft_error.fcstd
(73.89 KiB) Downloaded 18 times
the geometry check for the fusion of all lofts is okay.
abdullah
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Re: Loft over multiple sketcher bsplines fails

Post by abdullah »

I do get an error (appearing in the middle of the 3D viewer):

BRepFill profiles are inconsistent

I fact I can loft everything but the top profile. I have done it with part loft and with partdesign loft:
skip1_section6.png
skip1_section6.png (29.1 KiB) Viewed 1099 times
skip1_finalresult.png
skip1_finalresult.png (30.71 KiB) Viewed 1099 times
My modified file:
loft_error.fcstd
(237.12 KiB) Downloaded 11 times
abdullah
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Re: Loft over multiple sketcher bsplines fails

Post by abdullah »

The first two sections give weird results when including the top one:
section1.png
section1.png (11.21 KiB) Viewed 1099 times
section2.png
section2.png (20.3 KiB) Viewed 1099 times
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microelly2
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Re: Loft over multiple sketcher bsplines fails

Post by microelly2 »

thank you, so I have to understand what is different in the first profile.
the profiles are generated from a scan,
I want to have on this way a first view of the scan result, where still no user intervention was done.
thats why I have to modify the splines by script on the first try.
abdullah
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Re: Loft over multiple sketcher bsplines fails

Post by abdullah »

microelly2 wrote:thank you, so I have to understand what is different in the first profile.
the profiles are generated from a scan,
I want to have on this way a first view of the scan result, where still no user intervention was done.
thats why I have to modify the splines by script on the first try.
Welcome!

It would help tons to identify what OCC considers to be an "inconsistent profile" for BRepFill. I did a cursory search without any satisfying result.

The fact that it combines just fine the top two sections, and then when adding the a third one it goes nuts is very frustrating. I was thinking of orientation and seam, but then why is ok for the tool to loft the top two sections and go wild with the third?
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microelly2
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Re: Loft over multiple sketcher bsplines fails

Post by microelly2 »

There is always a workaround for loft and sweep.

I will discretize all curves and build a grid what I can use for a bpline surface or at least for a quad mesh. this is good and fast enough for the first step.
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