One way is to orient the object facing exactly the way you want to see it. Go to the 'Faces' sub-object level (Edit Poly) and in the 'Selection' section, turn on 'Ignore Backfacing'. Now, markee drag around your object. The backfaces won't be selected. Now just hit 'Ctrl+I' to invert the selection and hit 'Delete' on the keyboard. The backfaces will be deleted.
Depending on the shape, some faces you want might still get selected so sometimes you have to manually alter the selection set to make sure you don't delete something you really want to keep. But this can save you a lot of time if there are 100 or faces to delete.
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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