Why does adding a subsurf modifier cause this large flat face to deform?

Question

I'm very new to blender so this might be an easy fix, but I have a little problem with the model of my guitar. Here's what I'm working with right now:

But when I add the subdivision surface modifier, the tops go crazy, the big flat faces are not completely flat any more, and there's something wrong with the top and bottom of that carved out part... I would also like to make the edge of that less sharp but I haven't found a good way yet.

For reference, here's a picture of the guitar I'm trying to recreate:

What would you suggest to improve my model? Thanks for the help!

Subsurf works best with quads, and doesn't like ngons (faces with more than 4 vertices). — batFINGER, Mar 29 '20 at 15:21
Hello and welcome :). There seem to be more problems present, as others pointed out. You can share your .blend file so others can take a closer look at the model. — jachym michal, Mar 29 '20 at 15:28

score 4 · Answer 1 · answered Mar 29 '20 at 17:15

4

Thanks everyone! I now know that i should stick to four points as much as possible and I fixed it! I tried to make a grid on the huge faces and I got rid of as many triangles as possible and I'm very happy with the result :)

Now onto the rest of the guitar!

answered Mar 29 '20 at 17:15

Shanna Henselmans

71
3

Good one. Just restrung my strat.... I wish, strat copy. – batFINGER Mar 29 '20 at 17:31

score 1 · Answer 2 · answered Mar 29 '20 at 15:29

Subdivision-surface work best with quads. Triangles and ngons causes artifacts. Checkout this answer. Generally, use quads if you plan on using subdiv.

For example, you can probably form quads in the main body face of your guitar. And if you were planning to use subdiv, you could start off with fewer geometry to form the silhouette. Advice at this point is to look for tutorials on 3D modelling.

score 0 · Answer 3 · answered Mar 29 '20 at 15:25

You need to get rid of the N-gons(the triangles) in your topology, you can do this by adding an edge loop around where the triangles are, so something that goes over this area. If you can't add an edge loop that'll go over all of them try to get an even number of triangles there, that way it won't mess up your topology.

Why does adding a subsurf modifier cause this large flat face to deform?

3 Answers3