Weird smoothing issues???

When I try to smooth a surface with a Subsurf Modifier…sometimes the object gets these wierd lines with shadows around them when I hit set smooth… It’s an object like a tube. It should be smooth all the way around but it draws it like it has indented lines with shadows through the tube. I hope this makes sense. When I render it… it looks ok but it is hard to model with this problem. Has anybody else come accross this issue? I am using 2.46 and I have a GeForce Nvidia 6800 XT with the latest drivers. Thanks!

It may just be flipped normals. Cylinders seem to be bad about that. In Edit more select all (press A) and then press Ctrl-N to recalculate normals. See if this fixes the odd shadows.

The problem is probably not the normals, but triangles. Whenever possible try to use quads only. That’s kind of a pain with cylinders, but it can be done.

Just did a little test. If you have one vertice at the center of an end of a cylinder used to form faces with an outer ring of vertices, you can put a ring/rings of vertices between this center vertice and the outer vertices. Use quads. Hope this helps.

In edit mode select all and hit Alt+J to join all tris.

bah. No offense killer, but I dont like the logic the alt J uses to decide which tris to convert to quads. Druther do it myself…