Hardsurface modeling tip and are NGons bad?

In this video I show some hard surface techniques and I ask the question if ngons are to be avoided in general.

Would be nice to read your optinions and to discuss this topic.

There’s two things that can go wrong with n-gons. Distorted UV unwrap with normal unwrap method, and triangulation when the n-gons are concave or non-planar.

Unwrap with the seams like in the video. The side pieces aren’t unwrapped correctly.

Different seams, having less cuts, same

Side n-gons selected, mesh -> clean up -> split concave faces, then unwrap. The unwrap doesn’t get distorted sides anymore.

In this case it’s quite trivial to get rid of the n-gons and get the unwrap fixed, and without having to unwrap them separately with projection. That’s not always so easy. If the mesh has a lot of n-gons, can’t really go and unwrap each from view, and bevel doesn’t always agree with n-gons with or without splitting them. Let alone using it to get a nice perimeter loop around hard edges to support subdivision.

With non-planar polygons the usual culprit is that the structure flow doesn’t follow the form and have to redirect it so it does, or in some cases add more geometry to make the angles between faces smaller like in the linked example.

Yes. It’s not always necessary to remove n-gons, but there’s a whole lot to it.

I am no UVW expert but can that UV layout be packed better with the separate rect fitting under the lower arm of the main face set then scale it up to 1:1

Yes, this is true, thx for pointing this out, but it’s more a Blender bug than that ngons-concept is bad. What often helps in this case is to add a triangulation modifier, apply it, then turn tris to quads with all polys selected.