Mirror + Subsurf = UFO

I wish to model a nemo but :frowning: wow…it ended up looks like a UFO. First I model half side of the nemo. Then I use mirror to create another side of the nemo (the 1st attachment) but when I add subsurf to smoothen my little fish, it smoothen even the joint part of the fish at the center and ended up look like the 2nd attachment. Anyone knows how to fix it?


In the mirror modifier select Clipping. It also looks like you have a face in the middel of your mesh along the mirror line, delete it, you do not want internal faces.


Dear Alice,
I think that one of the possible reasons is that your mesh has some vertexes in the middle (the face on which the mirror passes). I would make sure that the points in the center of symmetry are exactly aligned to the mirror, and I would remove the points in the “not visible” plane.
I hope that the following attachments explain what I’m saying:

fig 1: The solid WITH the internal vertexes, after the SubSurf
fig 2: The points I’m deleting
fig 3: The solid after the delete operation.

I hope it helps… Consider also the clipping parameters in the modifier (I don’t really know how to manage it, but try checking/unchecking).



Oops… I notice now that there was already an answer… I began working on it at 17:05 (I clicked “reply”), and finished at 17:30… in the middle Richard had answered…
Btw, the order of the attachments is opposite to the figure caption.

ho ho ho…it works. thanks alot.