Why there is no Control point in loft?

Why there are no control points to twist the shape on the left example when trying To loft it?

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The control points are only showing up in specific cases. What is the desired Model you are trying to create?

iā€™d Like to make this kind of bowl but no idea how to do in shapr IMG_1086

You can create multiple cross sections and use the loft tool to create this shape.

For the cross sections:

  • use construction planes at different levels
  • offset the original sketch at every level and rotate them
  • loft the sketches
  • shell the object if you need to (if you were using full sketches)

Do you want me to show this in a tutorial?

I tried that way you said. But the it shows like this ā€˜ zigzagā€ curve not I planed ā€œsā€ curve from bottom to top. I tried to rotate 10 degree of each slice sketch, so that from bottom to top including 21 slices which will have 270 degree twist to make the ā€˜sā€™ shape twist. But it shows the twist of every two slices but not twist from bottom to the top slice. Can you show me how to deal with this?

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Not sure where things go wrong for you. I suspect that you donā€™t rotate accordingly as it looks like one sketch is rotated, the other is not, the next one is rotated, but the next one is not. Thatā€™s why you get the zigzag.

Attached a very basic twisted loft I did just now. Only 3 cross sections, scaled and rotated (40 degrees than +50, so 90 degrees).

loft

Can you share your .shapr file? Iā€™ll take a look at what goes wrong for you.

I think the problem here is that you are using too many profiles. Try do the same with less, eg. delete every second profile or even more.

I have tried doing it with a LOT of profiles. Works perfectly.

I am pretty sure the ā€œtransform + rotateā€ part is where things got mixed up for you. Every other profile is rotated, but then the other ones are not. Thatā€™s why you get a zigzag.

With bad and good transform at the same time I could recreate the zigzag (bottom) + the correct twisted loft (top) as well.

I intentionally created a ā€œbad partā€ in the middle. I think you make this mistake too.

zigzag

And I tried a new file , still can not work. This time only 6 slices and 20 degree increased each , from 0 degree twist to 100degree. Can I send you my shapr file to you and help to check please? Could you leave your email to me that I can send, thank you.

And one more question if I need to a precisely bowl side curve as like the sketch, it really need many slices to meet the curve. Do we have easier method to do this kind of shape?

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/ sorry I canā€™t get it, where are the profiles? How to delete ?

Send it to gabor@shapr3d.com.

Currently there is no easy way to match the S curve, you have to do it
manually. In the future we plan to improve this feature too.

G

Sent it to you just now. Please check

Btw, why canā€™t I see the reference image inputted before update the app? But click it , it shows up, /??

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Yes, thanks. This is a bug, we will fix it. Thanks for the report :slight_smile:

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Hereā€™s a video how to do the twisted + lofted vase:

There is no audio, just the video. Hope itā€™s useful.

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Thank you very much for your reply . And I tried to follow your tutorial with exactly same number and the same degree and got the same results as you, very happy about that .

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But when I try to do again with different degree for example 30Ā° twist of each section, I got the ā€œzigzag: again. ;(

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we really donā€™t know what happened , I just did that exactly follow your tutorialā€™s process but just change the rotate degree number . One problem I have to mention is that when I do the sketch ,I frequently use the ā€œundoā€™ button during some manipulations , for example when I do move and copy one slice up but I got the wrong distance so I click the ā€œundoā€ to try to back but the purple color axis instructors of free transform can not to follow the center of before, it stays the center of last cancelled.

And I tried some other test of the twist loft from simple shape of the Square , when I twist like a 45Ā° of each slice increased the loft result looks good after,
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but I do another example that the twist 90Ā°, to become a straight one,

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the 3rd test I did is I didnā€™t change rotation axis to front view, each slice twisted 90 degree increased from 0 to 270 degree, the loft result became like this no idea about that . I did not move them front or back or right or left just rotate those sketch slices.

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The problem with ā€œround number rotationā€ and ā€œregularā€ sketches is that the
program doesnt know which edge is which one.

You have a rectangle for example. Rotate it by 90 degrees. Its the ā€œsameā€
rectangle, not a rotated one. Because you cant assign which angle is which
one.

So when you rotate by 20, 30 degrees in some cases you end up perfectly
aligning the sketch, just they are vertically moved. In these cases these
look like that they are not really rotated.

If you move a rectangle and rotate it by 90 degrees, is the same as if you
only move it.

Itā€™s the same with your vase. Going with 20-30 degree rotations will
alwalys result in a zigzag. You have to go with ā€œnot roundā€ numbers to
avoid this for regular shapes.

With irregular shapes, this problem doesnā€™t exist.

G

Btw you can expect improvements in every tool, including the loft tool in the next few months.

Ok, I see. Thank you very much for your explanation, wish we can twist in any degree later.

yes, looking forward to having that later. Thank you, btw, if you need Chinese help free to tell me, I found the your feedbacks in Chinese on App Store seem like robot generated. :wink:

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Well, we are google translating them :slight_smile: