Can I use bird's nest putty nails without antirust paint?

You can't. Rust-proof paint must be applied to the ceiling of the putty-scraping nail, especially in engineering projects. Nails on the ceiling will not pass the acceptance without painting, because the nails used in gypsum board ceiling seem to have oil. In fact, these oils are used to prevent nails from rusting before use, and once they are used on gypsum boards, they lose their antirust effect. After the ceiling is completed, nails should be coated with antirust paint mainly to prevent rust.