Red Seal Auto Body and Collision Technician Practice Exam

What is a major consideration when selecting a primer for auto body repair?

1. Color variety available

2. Cost-effectiveness

3. Compatibility with the topcoat and the substrate material

4. Brand reputation

The correct answer is: Compatibility with the topcoat and the substrate material

In auto body repair, selecting a primer involves essential considerations to ensure the best adhesion, durability, and overall quality of the finished paint job. The major consideration in this context is the compatibility of the primer with both the topcoat and the substrate material. When a primer is compatible with the topcoat, it allows for a chemical bond which enhances adhesion and prevents issues such as peeling or flaking over time. Additionally, the primer must also be compatible with the substrate material—whether it's metal, plastic, or fiberglass. This compatibility is crucial to prevent chemical reactions that could compromise the integrity of the repair and the aesthetics of the finish. Other factors like color variety, cost-effectiveness, and brand reputation do play roles in the decision-making process, but they are secondary to the fundamental requirement of ensuring that the primer will work effectively with the subsequent layers and the materials being repaired. Focusing on compatibility helps in achieving a long-lasting, professional-looking finish that meets industry standards.