Having smooth shading problems

Hi folks. I expect I’m making very basic mistakes, but I don’t know what they are. I watched the CG Cookie YouTube videos that were linked in one of the stickies and that helped me improve the shading a bit, but it still isn’t right. I followed the general guidance of minimising the use of n-gons and tris, but I was still left with two tris (selected in the screenshot) that I couldn’t figure out how to get rid of. Given that the remaining tris are so small, though, are they actually what’s causing the uneven shading? I also thought it might be something to do with some of the quads being too rectangular, but if I split them I’m inevitably going to create n-gons elsewhere unless I start adding otherwise redundant geometry down the entire length of the blade. I’ve uploaded the blend file just in case it helps.The collections are a bit all over the place because I started making this thing in 2.79. I tried to simplify the modelling process by breaking the sword down into smaller parts, putting each part on a seperate layer, and then bringing them together into one mesh when I’d got the basic shope of each part right. When I tried connecting the blade to the brass/bronze connecting bit though, I started getting these shading problems. I thought I’d better ask for help on here before I try anything more, because I expect I’m more likely to just make it worse, rather than better.

katana-16.blend (837.4 KB)

Oh and I made certain it wasn’t caused by light bouncing off the blade and on to the bronze-iish block by deleting the blade’s polygons and seeing what that looked like. The shading still looked the same without the blade.

Bevel can help out with things like this, umm I would try the modifier, and add in a vertex group to control it by if that helps out.

What version of Blender is it saved with? When trying to open the file, Blender 2.79 instant quit.

Oh that file was saved in 2.8 rc1. The colloections are a bit over the top because when I started it on 2.79, I had each part on a seperate layer. When I opened the file in 2.8 beta, though, it looks like it changed each layer to a different collection. Sorry about the confusion.

Edit: Haven’t tried the possible bevel solution yet. I’ll be trying it in a little while.

i’m doing some guesses from the screenshot given. First check if the faces are planar. If not, you can select the face ring or both boundary loops and scale them to 0 on the appropriate axis. You can also select both boundary loops and mark them sharp. This will split the shading between the sections.

Looks like a non-planar quad there. The loop tools add on (ships with blender) has a “make planar” function. Possibly it will affect adjacent faces as well and you have to tweak a bit. Or you adjust your vertices manually until the shading looks right, as the mesh is still quite low poly.

Is your goal quad modeling, especially to be used with subdivision surface modifier?

It seems that you did not do that correctly here:
katana-16_mod.blend (849.9 KB)

Bridge the selection there (Bridge Edge Loops). So then you can add subsurf modifier and add supporting edges:

Quick way where to place sharps