These Japanese precision made cutting guides are specifically designed so you can cut accurate shapes and strips of differing length and sizes. This allows you to cut complex curves and different thickness of strips of masking tape. These will work great along with Tamiya Masking Tape or similar washi tapes, or any adhesive tape for that matter!
This S guide makes 0.5, 0.6, 0.7, 0.8, 0.9 and 1mm line tapes. Be sure to use on a cutting mat to prevent damage.