Auto Paint Undercoats and Primers

Undercoats

• Definition: Products used to prepare a vehicle for color and gloss coats of paint, including basecoats, clearcoats, and single-stage coatings.
• Key qualities: adhesion, corrosion protection, filling, and uniform color appearance.
• Application methods: spraying, brushing, or wiping.

Primers

• Function: Provide adhesion and corrosion protection as the first stage in the undercoating process.
• Application: Generally non-sanding, applied in a wet-on-wet process.

Plastic Treatments

• Key properties: adhesion and flexibility.
• Plastic adhesion promoters (plastic etch primers) used for raw thermoplastic substrates like bumper covers.
• These promoters chemically etch the composite for better adherence of subsequent coats.

Metal Treatments

• Types: metal conditioners, metal etching wipes, and metal etching primers.
• Metal Conditioner: acidic solution that deep cleans and conditions metal, leaving an iron phosphate coating.
• Metal Etching Wipes: pre-saturated wipes forming a chemical bond with the metal, require gloves due to acid content.
• Metal Etching Primer: provides excellent corrosion protection and adhesion on steel, aluminum, and zinc-coated substrates.

Epoxy Primer

• Benefits: excellent adhesion, corrosion protection, and minor filling capabilities.
• Extends the life of recoating without sanding.
• Application: reduced with a catalyst and epoxy reducer, with some requiring induction time for chemical cross-linking.

Primer Surfacer

• Use: widely used in the auto body industry for filling sand scratches, minor imperfections, and surface leveling.
• Types: available in various forms such as spray, roll-on, and squeegee-on.
• Must be sanded before topcoating.

2K-Urethane Primer Surfacer

• Definition: industry standard, requiring two components to crosslink and cure the product chemically.
• Offers exceptional filling, resistance to shrinking, easy sanding, and faster dry and cure times.
• Application: only over properly prepared and treated substrates.

Water-Borne Primer Surfacer

• Advantages: low VOC content, suitable for areas with strict environmental regulations.
• Often packaged ready to spray, containing rust inhibitors, and may be applied directly over bare metal.
• Limitations: may take longer to cure in high humidity conditions, and elastomeric additives will not mix with water-borne products.

Direct-To-Metal (DTM) Primer Surfacer

• Function: eliminates the need for a separate primer.
• Offers corrosion protection, adhesion, and filling capabilities in one product.

Application Procedures

• Undercoating/Underseal Application: involves cleaning the surface, masking mechanical components, and applying the undercoating in two coats.
• Primer Application: varies by manufacturer, refer to technical data sheets for specific instructions.

Safety Legislation, Regulations, and Industry Policy

• Overview: focus on understanding and applying safety laws and regulations in Alberta's trades.
• Objectives: Occupational Health and Safety (OHS) Legislation.
• OHS Act: establishes the rights and duties of employers and workers.
• OHS Regulation: details specific safety standards and requirements.
• OHS Code: provides practical guidelines to comply with the Act and Regulation.
• Employer and Employee Responsibilities:
  • Employers: ensure a safe work environment, inform workers about hazards, and provide necessary training and equipment.
  • Employees: follow safety practices, report hazards, and use protective gear.

Learn about the products and techniques used to prepare a vehicle for painting, including basecoats, clearcoats, and primers.