change isolated surface

[PiE81]

Good morning.
I should make a change to an isolated surface.
It is a rather extensive surface, but the modification about a small detail.
Attached a screenshot. the part has been realized by applying a thickness to the surface (isolated) that I would like to modify. the modification consists in making the curve end of the particular upper (clear grey) coincide with the similar end of the lower detail.
How do you advise me to proceed?
I know that the question could be trivial, but as a beginner on the subject, I ask your support.

thanks to all

 

[320i S]

there is a need for a little more info, because there can be different roads, from the modification to the previous cracks, to the reconstruction of the entire area.
so on the fly, I would copy the main surface, I would extend it, (even the other side) I would cut it with a curve that best connects the tangences, I would create the connection supercie via sweep, I would unite everything and solidify.

 

[gianni55]

Hi.

I would return to the isolated surface before applying the thickness
that isolated surface is formed by multiple surfaces, you must eliminate and rebuild what is not connected
extract only the lateral surface (the one that does not connect)
extract the edge of the extracted surface
hide the extracted surface
cut the isolated surface with the edge you extracted
hide the edge

Now you have to reconstruct the portion of the surface you have eliminated with one that fits better.. .

you can try to build a higher junction curve and a lower then with the multisection rebuild it

(first and second ray sections, guide the fitting curves)

Let me know.

 

[PiE81]

thanks to your suggestions I took it in an hour.
apart from extracting and cutting the surface to be changed, I solved with a multisection surface by applying the appropriate tangences on the guide curves and the section that connects to the modified surface.

I had to apply a slight change to the projected profile, the spline that defines the tip of the lower detail.
but now I don't remember what [emoji16]sent by my iPhone using tapatalk