Hi Olga - it looks like this is due to some differing lengths between those 2 rails.

If you zoom in to the other non-rounded end of your sweep:



Notice how the initial profile between those 2 rails is quite slanted? One rail is sticking out more than the other one so the profile starts out slanted and continues slanted throughout the length of your sweeping, giving you that result that you don't want.

You might try trimming off the end of that longer part so that the profiles will be closer to starting more perpendicular to both rails rather than slanted between them.

Sweep also can currently be sensitive to the spacing between control points in the rail curves, which may introduce this kind of slanting as well. That is something that I plan to tune up in v2, but it kind of looks like in this case it is starting quite slanted at the beginning there due to the differing lengths so that is probably something to adjust first.

- Michael

Thanks Michael
Please notice this strange shape (simple way to draw cobra : ) )
In the area were rails are closer the height jump high up. Maintain Height option does not help. Rhino does not do this. Can you fix it in the next version? Or do you have any suggestion how to use better Maintain Height option. I know I can draw a curve defining the height and use it as scaling rail but instead I would think Maintain Height option should have helped but it does not.

Thanks
Olga

Hi Olga - those stretched shapes happen because of slanting connections in between the rails.

For example here is a cross-section taken from the center part of the MoI sweep:




Notice how that section is slanted between the 2 rails? That makes the section scaled up to be bigger, because a slanted section between 2 rails is longer than a section that is closer to perpendicular between 2 rails.

It looks like this is being caused by differences in control point spacing between the rails, which MoI's sweeper is currently sensitive to. But I am planning on doing some work to fix this up for v2 though, it is a fair amount of work so it won't be for the very next beta release but I plan to get it in before the v2 final release.

- Michael

Thanks Michael
I tried to redraw these rails with control points on oposite rails perpendicular but the same happens again. I even added more control points so that they coincide with the curve itself
I guess I will have to use another curve for scaling rail to control the height.
Could you please reply to my message #3

Hi Olga,

> Could you please reply to my message #3

Actually my previous reply was a reply to that message - did I miss something?

I was trying to show you there why that scaling happens - when doing a sweep, when the profiles stretch between the 2 rails they become scaled.

If "Maintain height" is set, that scaling happens only in one direction, otherwise in all directions.

When sections slide at an angle to one another, that creates a larger size of the section in the same way as if the rails were further apart or closer together to one another.


> I tried to redraw these rails with control points on oposite
> rails perpendicular but the same happens again.

Could you please post those curves so I can take a look?

- Michael