hello guys

When I simulate it, it appears normal at first, but from the frame of 4~50 there is a layer where the object has passed, and the edge is broken.

Why does this result? I have attached a file(Houdini 18).

And I'm following the lecture, but I don't understand the attached file, so I'm posting other questions.

1. If I don't use point cloud, I don't have to put in a normal node, right?

2. I have a question about divide node in ‘outline’ subnet. I checked the remove shared edge on the divide node and deleted a lot of sides, but when I test it by connecting it to another object, all of them disappear. I wonder what conditions can be used to partially delete it.

3. I created an outline of geometry on a subnet called ‘outline’ and used it for xyzdist in attribute vop node called ‘wrangel’. However, I wonder why there is no difference in the results shown in the viewport even if I sign on the ‘outline’ subnet called ‘outline’.