Subdivision Surface modifier destroys round shape

Hello everyone!

I’ve been working on a project and run into a few problems with the Subdivision Surface modifier.

So, let’s say I want a perfect round cylinder with three stripes attached to it’s sides. Something like this:
image

This is what happens when I apply Subdivision Surface modifier:
image


As you can see, the cylinder has lost it’s round shape when you’re looking at it from the top.
I was wondering if there’s a way to fix this, but keep using the Subdivision Surface modifier?

Here’s another example. I’ve been working on a transparent cylinder made from 2 acrylic sheets, wrapped around a top disc:

I created a model with all seams and cut offs (just like a real life object)

And applied the Subdivision Surface:

And this is the same problem with losing the round shape:


Here are me .blend files, if you need.


Thanks!

What I normally do is add a shrinkwrap modifier in the beginning to avoid having to use too dense meshes in cases like these. There are a lot of cad experts around here, I’m sure there are other/better ways.



Time Rotor_sw.blend (1.1 MB)
Cylinder With Stripes_sw.blend (786.5 KB)

1 Like

Thank you! This does seem to fix the problem