Trying to add molding in lunette vault arch

Hello everyone. In the reference images you can see the top arched lunettes i am modeling but the problem comes when i try to add those golding moldings to it.

Now the front molding is somewhat manageable but the one inside the vault curved part (I’ve marked it red in picture 4) i cannot make it because when i try to use different tools to make the profile follow the curve, it always messes the geometry from the sharp ends and i just cannot wrap my head around what to do.

I know i doing something wrong and there must be some rules i have to follow in order to successfully model this. I will share the model of the exact arched lunettes so if anybody wants to try it would be exact measurements and also the molding should start after the 4inch space from all the sides.

Thanks in advance.

Model link: https://drive.google.com/file/d/1D8VlfVg33ZHedbs2FmE4UnB1MNKEyG3f/view?usp=sharing

As an idea, with Fredo Tools on Surface, Fredo Spline, QuadFace Tools and Flowify.

:fast_forward_button: arcada.skp (450.6 KB)

@mihai.s Thank you soo much for your time. 2ndly what you are doing is running the profile on the front edge of the arch but what i want is to run the profile inside the vault like this image and you can see the problem i am facing. The profile does not follow the path and the end points becomes glitchy. Also this is how and where i want to run the profile inside the arch after 4inch spacing

The principle is the same, you offset where you need to.

:fast_forward_button: arcada2.skp (680.3 KB)

But even if i do it this way the sharp joint will not continue like the reference and if you say i should divide the molding in 2 parts then intersect it from the sharp joint it still wouldn’t give me smooth continues molding

@mihai.s I want to run the profile along this red path i’ve marked like the reference image

What you actually want is to follow that path but also a surface. Flowify helps you with this.

Ok I’ll play with it hope i’ll get the desired result thank you so much for your help

Considering that the shape of the vault allows it, you can create that molding in plan using Offset and Follow Me, and then, Flowify to give it the desired shape.

At the end of the video, I also showed how it can be done in Blender using a modifier (Surface Flow).

Adding molding to a vaulted ceiling in SketchUp and Blender