Problem: I'm making a brake-caliper, and I wanted to cut out these engraved shapes from the brake surface using boolean modifier. It first crossed my topology, which I thought creating the mistake, so I changed that the rotation angle and number of arrayed object are matching and they never cross each other. The problem still occurs. I've watched a Blender tutorial of a brake caliper where the guy makes it with exactly this method and it works for him. I'm stuck because I don't know what am I doing wrong. I've had a similar question in the past where my topology was messy and I thought at the end that was the cause. I've also tried to apply the subdivision on the caliper itself - result was the same. The cutting objects go through the brake and come out on the other side.
Question: How could I use the boolean difference in this case to just simply cut out these objects? How's it possible that the same method works in the tutorial and not for me?