how do you loft to a non-flat shape/surface?

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tsdexter
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Joined: Sat Jul 30, 2022 2:33 am

how do you loft to a non-flat shape/surface?

Post by tsdexter »

I want to make a shape similar to this:
Lampshade_800px_600px_4.jpg
Lampshade_800px_600px_4.jpg (138.06 KiB) Viewed 731 times


It looks like it can be done with a loft? For example, make a pentagon sketch, hexagon, and decagon and loft between them... However, the middle sketch is not flat, every other point is offset a little higher on Z... How can I do this?

If a loft is not the right approach for a shape like this, what would be?

I see lots of results looking up vase mode/lofting/etc on youtube and here but it's all simple flat sketches, no 3D surfaces.

Thanks!
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onekk
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Re: how do you loft to a non-flat shape/surface?

Post by onekk »

This resemble more a mesh than a solid.

I doubt Loft will make "facets" correctly

Probably the most easy way is to create "facets" extrude them and assemble using a boolean fusion, but you have to calculate all the "facets" position.

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hammax
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Re: how do you loft to a non-flat shape/surface?

Post by hammax »

... it's possible with facets and polar array:

Screen.PNG
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Last edited by hammax on Mon Oct 03, 2022 4:29 pm, edited 1 time in total.
chrisb
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Re: how do you loft to a non-flat shape/surface?

Post by chrisb »

I don't see a loft here, because in the middle the section is not on a plane. It looks rather like a base shape and some cutting arrays.
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tsdexter
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Re: how do you loft to a non-flat shape/surface?

Post by tsdexter »

hammax wrote: Mon Oct 03, 2022 6:33 am ... it's possible with facets and polar array:


Screen.PNG
thanks a lot, thats awesome for you to take the time to do that... unfortunately, I'm too much of a newb to understand exactly what you did to get to the final file... would love a screen record while doing it if you have the time, although I certainly don't expect you too... I will still try to reverse engineer from the file in the meantime. Thanks!
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hammax
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Re: how do you loft to a non-flat shape/surface?

Post by hammax »

... here a more simple parametric arrangement.
Draft lines are not parametric => CurvesWB lines follow changes of the cross sections.
The position of the vertex is adjustable, also the height position of cross sections.

Screen_3.PNG
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Shalmeneser
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Re: how do you loft to a non-flat shape/surface?

Post by Shalmeneser »

:idea:
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