How is a guide coat used in bodywork?

How is a guide coat used in bodywork?

• A. It reveals high and low spots when rubbed
• B. It protects against rust
• C. It seals gaps
• D. It acts as a top coat

Answer: (A)

A guide coat is a diagnostic tool used during sanding to reveal surface imperfections. You apply a thin, contrasting layer of pigment over the repaired area, usually over primer or a base coat. As you rub with a sanding block, high spots are shaved down and the guide coat is removed there first, while low spots retain the coating longer. This contrast makes any unevenness stand out, showing exactly where material needs to be added or feathered to create a smooth, flat surface. It’s a temporary aid for leveling before you proceed with primer and paint, not something that protects against rust, seals gaps, or serves as a top coat.