Subsurf modeling problem/question

I’m modeling a lighter as a learning exercise and I’m running into the same problem I’ve run into in the past. Whenever I need to add a detail to something connected to the same mesh, and add a knife loop cut to alter the edge intensity, it creates ugly seams where I don’t want them.

Here’s a picture of my WIP lighter (notice the seam below the little notch at the top of the oval):

And my mesh:

Any idea how I can avoid this? I’m really new to blender, but just about every time try subsurf modeling, I end up with this same issue.:ba:


when using subsurf around holes or sharp things
you need to add up to 3 more loop near that edge to ensure that the subsurf will work fine

it should be fine - let us know what happen


Hi Ricky. Thanks for the reply. What do you mean exactly? Can you maybe draw on my mesh in MS Paint or something to show me where you mean to put the loops?

not certain witch detail in the pic

so can you show me with an arrow the details that you meant

then i might be able to help some more


Well, as much as I know, subsurf subdivides the mesh and smooths it with a strange algorythm. It subdivides ALL the edges the times you set, the small ones as well as the large ones. The algorythm a sort of averages the verts and creates the smooth surface from the average values. When you have mmany verts in the same area, they have very much influence on the new surface so they create ugly seams. I’ve already faced this problem, and I solved it by really low-poly model and some bump/normal/displace maps. Another way is sculpt smooth, but the maps worked well. Hope this helps!

PS: Sorry about the “average verts” thing, but I can’t explain better…

that’s the idea of subsurf on vertex inlfuence all the verticies around it
that’s why it is so powerfull and it also add verticies between exsiting one ( function of levels setting ) but also time consumming for the render time

but it will smooth things all over so if you need edges shrarp then you ahve to make them sharop with Ctrl-E