Circle round shape wobbles when rotating

as you can see in the image, there si circular shape in the middle - if i try to rotate it along its round side it wobbles up and down

it seems to be perfect circle and even if i take outline (edge) and compare it with newly created circle it both creates an object, that perfectly fits (the rounded object in the front)

the point is, that if i duplicate the middle object and keep rotating one - it is visible form isometric view (right/left in this case) that they do not cover each other perfectly

furthermore, if i join the last object (quater-egg-like shape in the back) to to cicrle one, it wobbles even more. The back shape does not exceed the circle dimension, so i expected that these two object together will share the same center of rotation given from the full circular shape. The difference is quite big at that moment and even shaper calculate different position after rotation

I checked that the back object does not exceed the circle object by using the outer circle outline to cut any exceeding parts on the back one - but it did not cut anything, it simply created a new object around the back one. (i would add an explanation screenshot in the comment)

the outer oultine of the circle is clear with no parts exceeding in or out. I get, that this could change the center of the mass, but this is not the case

the object is 89.7mm in diameter and the difference is 0.2mm

the origin of this possibly comes from the fact, the object was created from rotation of a sketch, then shell.

But why does it translate to clean circle in one case and then behaves like this … or is it only display glitch?

as mentioned above - checking that no part of the last object does not exceed the diameter of the middle one …

Can you try and share the Shapr file?

hey @JakubUrban! Can you tell me what is the axis of the rotation?

I may not fully get the description, but I guess that the misalignment is the result of the default placing of the pivot point. If you select the full body, the pivot will be placed in the CG of the part which may be different than the center point of the circular edges if there are cutouts in the body.