Hi niko,

> a result of imperfect tangency or simply the outcome
> of having a second surface created inside another one?

Looks like imperfect tangency.


> If I were to manufacture that part would those lines
> be there?

It really depends on which manufacturing method you were using.

But it's not too likely that such a small subtle detail like that is actually going to come through the manufacturing process.

- Michael

Ok what can I do to perfect this, short of using the cut and blend method?
The middle (kink curve) is the outcome of a projected curve on the bigger surface(after the initial cut), then blended and then points moved or cutting and orienting a smaller section curve and then blending it again.
I hope that makes sense Michael..
Thanks in advance.

Hi niko - the easiest thing is to not worry about it - if you are manufacturing this part there is no way that tiny level of detail is going to make it into the end result.

Otherwise if you want to get a smooth result between pieces you need to use Fillet or Blend to generate continuous surfaces, other techniques won't work.

- Michael

Or also you might want to use Rhino and try the MatchSrf command in Rhino which is an editing tool that adjusts an untrimmed edge of one surface to be smooth with another. It could help you in this kind of situation.

- Michael