Hi Pilou, yes that's normal that a blend curve is not exactly the same as a circular arc, is that what you are asking about?

A blend is a general spline curve, not a conic section, it can even get constructed as an S type shape completely and totally different in shape than an arc, like this:



Blend is meant to be more like a flexible bendy type thing that can smoothly connect any type of pieces, it's not meant to only generate an exact arc shape. If you want to make an exact arc, you should use one of the arc drawing tools for making that instead of Blend.

- Michael