I’m trying to build an arcade machine for fun and I realized that when I make a union for the ball to fall and go through a part so the person can grab it the union doesn’t physically change anything only the appearance. I know that it’s just what union does and makes in useless and annoying but is there another tool I can use?
Try changing the union’s CollisionFidelity to PreciseConvexDecomposition. This will produce the most accurate (and most expensive, so use sparingly) collision geometry. You can learn more about fidelity settings, their costs, and their applications here.