Lofting problem
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URL: https://www.cadforum.cz/forum_en/forum_posts.asp?TID=10659
Printed Date: 05.Sep.2026 at 04:16
Topic: Lofting problem
Posted By: Mali Zeleni
Subject: Lofting problem
Date Posted: 06.Sep.2014 at 16:36
I prepared closed profiles for lofting, but I encountered a problem. Can somebody tell what could be the problem?
Here are some picture illustrating the problem:
 Profiles in red denote the place of irregularity in the lofted 3D solid.


 Thank you for any help.
------------- Kind regards, Hrvoje
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Replies:
Posted By: John Connor
Date Posted: 06.Sep.2014 at 18:16
A copy of the drawing would be needed to troubleshoot the problem.
------------- "Humans have a strength that cannot be measured. This is John Connor. If you are reading this, you are the resistance."
<<AutoCAD 2015>>
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Posted By: Mali Zeleni
Date Posted: 06.Sep.2014 at 19:57
Thank you John for your answer. Here is the file with the drawing:
uploads/497931/VL_za_krmenu_protustatvu_-_2.dwg" rel="nofollow - uploads/497931/VL_za_krmenu_protustatvu_-_2.dwg
In the meantime I found out that the closed profiles are not of the same type. There are polylines (green), splines (yellow) and 3D polylines (blue).
 In the next step I added one profile on the place where the solid has discontinuity in the form. The first blue line, lower. Also, I started to loft from the top (!?) and the form was better. On two places I have the irregularity in the surface. I don't know yet, how to solve this problem.


------------- Kind regards, Hrvoje
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Posted By: Mali Zeleni
Date Posted: 06.Sep.2014 at 21:02
 If I avoid critical part of the solid it looks fine.  Now must find the way how to close the gaps.
------------- Kind regards, Hrvoje
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Posted By: John Connor
Date Posted: 06.Sep.2014 at 22:18
I guess you aren't going to upload a copy of the drawing. OK. Good luck.
------------- "Humans have a strength that cannot be measured. This is John Connor. If you are reading this, you are the resistance."
<<AutoCAD 2015>>
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Posted By: Mali Zeleni
Date Posted: 06.Sep.2014 at 22:19
If I use each third profile solid looks much better. Also the geometry is not accurate as it can be.
------------- Kind regards, Hrvoje
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Posted By: Mali Zeleni
Date Posted: 06.Sep.2014 at 22:21
John Connor wrote:
I guess you aren't going to upload a copy of the drawing. OK. Good luck.
| Yes, I uploaded the copy of the drawing in one of the previous posts (at 20:57). I will check if I can open it.
P.S. I checked: it is possible to open the drawing.
------------- Kind regards, Hrvoje
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Posted By: Mali Zeleni
Date Posted: 07.Sep.2014 at 21:43
I refined the geometry and the 3D solid looks better.

 I still have two places on the solid which should be put in order. Is the lofting bad approach for such body? I see that only one surface is not good: all surfaces located in one plane are OK. The flow of lines on curved surface seems to be "drunk".
 Here is the copy of the drawing:
uploads/497931/VL_za_krmenu_protustatvu_-_2_-_Copy.dwg" rel="nofollow - uploads/497931/VL_za_krmenu_protustatvu_-_2_-_Copy.dwg
I thank for each answer.
------------- Kind regards, Hrvoje
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Posted By: John Connor
Date Posted: 08.Sep.2014 at 12:24
Looks like you are getting helped over at CADTutor so there is no need to continue the conversation here.
------------- "Humans have a strength that cannot be measured. This is John Connor. If you are reading this, you are the resistance."
<<AutoCAD 2015>>
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Posted By: Mali Zeleni
Date Posted: 08.Sep.2014 at 13:26
John Connor wrote:
Looks like you are getting helped over at CADTutor so there is no need to continue the conversation here.
| Consequently, because I am the member at CADTutor forum, there is no need to be the member of this one. Right?
------------- Kind regards, Hrvoje
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Posted By: John Connor
Date Posted: 08.Sep.2014 at 14:34
Mali Zeleni wrote:
John Connor wrote:
Looks like you are getting helped over at CADTutor so there is no need to continue the conversation here.
| Consequently, because I am the member at CADTutor forum, there is no need to be the member of this one. Right?
|
That's entirely up to you. No one is suggesting you leave.
------------- "Humans have a strength that cannot be measured. This is John Connor. If you are reading this, you are the resistance."
<<AutoCAD 2015>>
|
Posted By: SEANT
Date Posted: 09.Sep.2014 at 09:54
I suggest isolating loft operations to just the pertinent geometry. Extend the geometry as needed to create a surface large enough to slice a solid made from more basic (Box) primitives.
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