Which sanding grit is typically used last before priming on metal panels?

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Multiple Choice

Which sanding grit is typically used last before priming on metal panels?

Final prep for primer on metal should yield a very smooth, uniform surface with minimal visible scratches. Using an ultra-fine grit like 1200–2000 gives the finest scratch pattern, which helps the primer adhere evenly and reduces the chance of show-through or texture in the final paint job. This step often involves wet sanding to keep dust down and to further soften any minor imperfections, creating a clean substrate for priming. Coarser grits leave deeper scratches or a rougher surface that can hinder adhesion or telegraph through the finish, while slightly coarser grits (600–1000 or 320–400) are better for shaping and removing larger imperfections but not for the final touch before primer. Thus, the last sanding before priming on metal is best done with very fine grit to achieve the smoothest possible base.

Final prep for primer on metal should yield a very smooth, uniform surface with minimal visible scratches. Using an ultra-fine grit like 1200–2000 gives the finest scratch pattern, which helps the primer adhere evenly and reduces the chance of show-through or texture in the final paint job. This step often involves wet sanding to keep dust down and to further soften any minor imperfections, creating a clean substrate for priming. Coarser grits leave deeper scratches or a rougher surface that can hinder adhesion or telegraph through the finish, while slightly coarser grits (600–1000 or 320–400) are better for shaping and removing larger imperfections but not for the final touch before primer. Thus, the last sanding before priming on metal is best done with very fine grit to achieve the smoothest possible base.

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