Gordon surface vs Filled boundary surface

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Piero69
Posts: 473
Joined: Thu Jul 04, 2019 1:22 pm
Location: Parma - Italy

Gordon surface vs Filled boundary surface

Post by Piero69 »

i tried to model a solid in which a circular top base turns into an elliptical lower one with two different paths.
Missing the necessary feature (a loft driven by curves) a direct solid modelling is impossibile because also the sweep with additional curve gives an absolute incorrect outcome.
The only way i found is a "step by step" surface modelling in which i create 1/4 of external skin and then mirroring it around the axis to get the entire shell after knitted them into an only one. To close the shell i create the top and lower planar surfaces with filled boundary surface and after knitted all them i solidify the model.

I tried to work both with "gordon surfaces" from Curve WB and with "filled boundary surfaces" from Surface WB finding an important difference (or maybe a bug), gordon surfaces don't keep (or don't have) the end condition "normal to edge". The section of model shows how the surfaces are convex in the junction point (see images)

on the contrary the filled boundary surfaces (by coons) seems to keep this end condition

what do you think?

also, do you have a different process to get such model in a better (and quick) way?
Attachments
Modelling with Gordon.FCStd
(132.74 KiB) Downloaded 12 times
Modelling with Filled boundary surface.FCStd
(48.44 KiB) Downloaded 12 times
Filled Boundary Surface.png
Filled Boundary Surface.png (94.89 KiB) Viewed 1483 times
Gordon.png
Gordon.png (99.63 KiB) Viewed 1483 times
imm
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Joined: Wed Nov 03, 2021 1:00 pm

Re: Gordon surface vs Filled boundary surface

Post by imm »

You may wish to review this thread.

viewtopic.php?t=78678
domad
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Joined: Mon Jun 22, 2020 12:16 pm

Re: Gordon surface vs Filled boundary surface

Post by domad »

Piero69 wrote: Wed Jun 07, 2023 9:15 am ....
Hello @Piero69, greetings to the Community!

A dynamic example (without the need to use the "Curves" wb) of how to manage the guided "Loft" (better defined as "Additive pipe") of three geometries (two ellipses and a circle) along a path, in this case path curved, in which the central ellipse automatically redefines itself as it moves along the curved path.
It is simply an example whose parameters can be expanded by creating new ones.
It is recommended to change the parameters using small increments in order not to send the solver into error.
Un saluto
Attachments
Modelling_no_Gordon_domad.FCStd
(50.44 KiB) Downloaded 9 times
Modelling_no_Gordon_domad.gif
Modelling_no_Gordon_domad.gif (504.77 KiB) Viewed 1299 times
Piero69
Posts: 473
Joined: Thu Jul 04, 2019 1:22 pm
Location: Parma - Italy

Re: Gordon surface vs Filled boundary surface

Post by Piero69 »

yes.. but the second paths is uncontrolled and not defined, sections must follow two definite paths to turn one into others. that's indeed the current limitation of solid modelling in FC.

Currently there is no way to make it in FC but an intricate work by surfaces that gives back just an approximative outcome.


domad wrote: Thu Jun 08, 2023 7:55 pm
Piero69 wrote: Wed Jun 07, 2023 9:15 am ....
Hello @Piero69, greetings to the Community!

A dynamic example (without the need to use the "Curves" wb) of how to manage the guided "Loft" (better defined as "Additive pipe") of three geometries (two ellipses and a circle) along a path, in this case path curved, in which the central ellipse automatically redefines itself as it moves along the curved path.
It is simply an example whose parameters can be expanded by creating new ones.
It is recommended to change the parameters using small increments in order not to send the solver into error.
Un saluto
paullee
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Posts: 5097
Joined: Wed May 04, 2016 3:58 pm

Re: Gordon surface vs Filled boundary surface

Post by paullee »

Interesting loft workflow :)

When the R_curvature_Path become smaller, the path on one side become uncontrollable.


Screenshot from 2023-06-10 16-20-36.png
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Screenshot from 2023-06-10 16-20-45.png
Screenshot from 2023-06-10 16-20-45.png (196.7 KiB) Viewed 1146 times
paullee
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Re: Gordon surface vs Filled boundary surface

Post by paullee »

How about simple Part Loft? No control of the path right ?



Modelling_no_Gordon_domad_R.FCStd
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Screenshot from 2023-06-10 16-51-36.png
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Screenshot from 2023-06-10 16-52-13.png
Screenshot from 2023-06-10 16-52-13.png (245.13 KiB) Viewed 1129 times
domad
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Re: Gordon surface vs Filled boundary surface

Post by domad »

Piero69 wrote: Fri Jun 09, 2023 5:47 am .... but the second paths is uncontrolled and not defined, sections must follow two definite paths to turn one into others. that's indeed the current limitation of solid modelling in FC.

Currently there is no way to make it in FC but an intricate work by surfaces that gives back just an approximative outcome.
Hello @Piero69, greetings to the Community!
A good compromise.
Another alternative, still using the "guided-dynamic loft" function (Additive pipe-dynamic) through the two paths (one curved, the other straight sloping), in this case the central geometry (the ring) is It has been realized using a spline that adapts to the sliding along the two paths giving rise to a good approximation of the curvature of the surface.
Attachments
Modelling_no_Gordon_domad_2.FCStd
(91.7 KiB) Downloaded 13 times
Modelling_no_Gordon_domad_2.png
Modelling_no_Gordon_domad_2.png (184.49 KiB) Viewed 1063 times
paullee
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Re: Gordon surface vs Filled boundary surface

Post by paullee »

@domad Thanks for the model.

Wondering but can't find how the straight edge is included in the loft path? Thanks.
drmacro
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Re: Gordon surface vs Filled boundary surface

Post by drmacro »

paullee wrote: Sat Jun 10, 2023 4:30 pm @domad Thanks for the model.

Wondering but can't find how the straight edge is included in the loft path? Thanks.
Each sketch (007, 009. 006) have external references to Sketch002.
Star Trek II: The Wrath of Khan: Spock: "...His pattern indicates two-dimensional thinking."
domad
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Re: Gordon surface vs Filled boundary surface

Post by domad »

paullee wrote: Sat Jun 10, 2023 4:30 pm ...
Wondering but can't find how the straight edge is included in the loft path? Thanks.
Hello @paullese, greetings to the Community!
I couldn't answer earlier, but @drmacro (many thanks! :) ) answered exactly
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