You have a flaw in one of the components. Have you welded the vertices? Have you run 'Mesh Cleaner' or 'STL Check' on them to make sure they are clean and manifold. Once you clean up the mesh I'm betting it will boolean properly.
Rob Holmes
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3ds Max (2023-2025), V-Ray 6.2, Ryzen 9 3950-X Processor, DDR 4 128MB, Gigabyte Aorus X570 Master motherboard, Sabrent Rocket NVMe 4.0 M.2 drives, NVidia RTX 4090, Space Pilot Pro, Windows 11 Pro x64, Tri-Monitor, Cintiq 13HD, Windows 11 x64
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