Applying Primer

  • When to Apply Primer: Always apply primer to unpainted surfaces, whether they are made of metal, plastic, or rubber.
  • Preparation: Before applying primer, ensure the surface is clean and free from any previous coatings or significant damage. If applying over existing paint, sand the area first to create a surface that primer can adhere to.
  • Using Primer with Body Filler: After using body filler apply a layer of primer to ensure smoothness and enhance paint adhesion. For non-metal surfaces, apply SEM Adhesion Promoter before the primer to improve bonding. Apply lacquer putty to fill deeper imperfections.
  • Application Technique: Spray the primer in several thin coats rather than one thick coat to avoid drips and ensure a smooth, even coverage. Allow each layer to dry according to the manufacturer’s instructions—typically overnight drying is beneficial to reduce shrinkage and improve adhesion.
  • Wetsanding Primer: Wetsanding primer is recommended as it creates a very smooth surface. The rule here is your paint will be as smooth as the primer so take care with this step. You can start with 220 grit and finish off with 600 or even 1000 grit.
  • Final Coating: Once you have sanded the putty smooth, apply a coat of primer to seal and smooth the surface before painting.
  • Further Information: For more details on the types of primers available and their specific applications, see the ‘Primer Products’ section under Product Information.
  • Electro Deposit Primer (EDP) Preparation:
    • Overview: EDP, short for Electro Deposit Primer, is a primer application method that was not widely used in original paint jobs from the 1960 era. Unlike earlier methods, EDP offers superior rust resistance and complete coverage by electrically depositing the primer onto the metal, akin to plating.
    • Preparation for Painting: To prepare EDP-coated surfaces for painting, simply lightly scuff the surface. This enhances the adhesion of the subsequent paint layers without compromising the primer’s protective qualities.