Expert Advice

Applying finishes

Before starting any painting project consider the 3 most critical questions:

  1. What preparation is necessary
  2. Does the substrate matter
  3. What repair and upkeep is needed

Step 1: Health and Safety

Before commencing preparatory work, ensure the area you are working in is adequately ventilated. Ensure you are wearing the correct PPE; we recommend safety glasses, goggles or visors, nitrile rubber gloves, overalls (ensuring skin is not exposed) and a solvent mask.

Previously painted surfaces:

Step 2: Inspection

Check for areas of damage, separation or peeling, or any other indications that the existing coating is not firmly adhered to the substrate.

Step 3: Preparation – in good condition

Remove surface contamination by wiping down with Interlux® Special Thinner 216 or Fiberglass Surface Prep YMA601. Once the surface is clean abrade with 220-320-grit sandpaper. Remove the sanding residue and allow to dry.

Preparation – in poor condition

If previous finish is cracking, peeling or showing signs of separation from the substrate all previous coatings should be removed and the substrate primed.

Step 4: Masking

Before priming/undercoating, mask off the area to be painted.

Bare substrate:

Step 5: Priming/Undercoating

To obtain the finest finish on fiberglass and wood and in the case of metal substrates the surface will need to be primed. Your choice of primer and undercoater will be dictated by substrate and choice of finish coat.

As gelcoat ages it becomes porous and brittle which may lead to cracking and blistering. To seal the gelcoat and get a finer finish apply InterProtect® 2000E or Epoxy Primekote.

Step 6: Application

Sand the undercoat smooth with 320-400 grit paper and remove dust with a wipe or tack rag.

Apply the finish, according to label recommendations.

“Achieve a perfect result every time!”

  • Ensure an even spread by holding the brush at 45° – this minimizes brush marks.
  • The best finish is achieved on large areas by two people, one to apply the paint, the other following immediately behind to ‘tip off’ the finish.
  • Clean or change brushes every 20 minutes or so. Always use lint-free cleaning cloths.
  • Stir the can occasionally during the work.
  • Dampen the ground with water before commencing painting to avoid any dust rising.
  • Use a worn brush for the final coat, this will ensure less brush marks.
  • Painting is best achieved on warm, dry mornings – cold weather retards drying and damp will spoil the gloss.
  • Never apply direct from the can as this will introduce contamination.
  • Always pour the amount of paint that you expect to use into a separate container.


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