Gradient black lines (CTRL+N don't correct)

2nd Edit this topic can be removed.
Not sure what I did wrong the first time I tried ctrl+N but didnt work for me. I decided to try again to see if there was a step or something that I missed, sure enough I missed something cause yes Ctrl+N worked (Removed Doubles did not play a part in it, there were none) - Thanks!

*Edited - Remove doubles do not help either

I have this bottle I am working on and it doesn’t (so far) affect the render but still it is deceiving while working on it.
Is there a way to remove them, or possibly prevent this from happening again if I start over (which really do not want to but if need be I will)?
Thanks for any suggestions/help that may be posted.

go to EditMode
select all (AKEY)
press (WKEY)
select “remove doubles”

I’m pretty sure this is a problem with normals. Try checking for internal faces. Or you could post the .blend so people can have a look at it

I get this problem too; it’s really annoying.

Hi Wolfprint,

Please post your .blend and we can take a look. All the usual
things have been suggested.

Kindest regards,


looks like a Normal prolbem

also you may see some dark bar in the viewport
but it doesn not mean that it will be visible in render
this is caused by lamps i think in viewport

but you could make a test by using the edgesplit modifier and chackout how it looks!

but if you can upload file we can look at it !
i did bottles like that before and there are no normals problem!

there might doulbes or the mesh may have some sort of tiwisted shape too!


It could be many things. if you tried to remove doubles, also Ctrl N to point Normals outside, also edge Split modifier, then i would suggest to check for vertex that are not connected.