Problems with smooth shading can you please help me? I need to fix this to make weapons for my game, I use boolean operators, and then active the smoothing, after activating the smoothing appears strange artifacts in my mesh, an example image - first image:



Then I add the Edge Split modifier or activate Auto Smooth, so the artifacts disappear, but when I add bevel, the artifacts appear again, only weaker or stronger,
example image - second and third image:




these artifacts are visible in unity, and in other programs, and this is very bad, is there any method that can fix this, please help me, can solve using flat shader, instead of smooth shader, it seems that the problem is smooth shader, but I need to use smooth shader.

sorry about my english, I'm from Brasil.
Try using bevel modifier with weight rather than edge split.

Select the sharp edges and assign mean bevel weight to 1 in side properties panel(n). Then change in bevel modifier bevel limit method to weight. play with width and segments. It works fine in blender, but I don't know in unity. Because of huge ngons in middle