Expert advice

How do I apply finishes?

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

1. What preparation is necessary?
2. Does the substrate matter?
3. Which painting system will I need?

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:

Clean with warm water and liquid detergent to ensure any residual polish, wax or surface contaminants are removed. Rinse with fresh water and allow to dry. Sand smooth with 180-220 grade paper. Clean thoroughly and allow to dry completely. Continue at Step 6.

In poor condition:

If previous finish is cracking, peeling or showing signs of separation from the substrate this should be totally removed.

Step 4: Masking

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

Bare substrate:

Step 2: Priming

Bare substrates should be primed to promote good adhesion and provide a smooth even surface, prior to undercoating. Your choice of primer will be dictated by the substrate; product recommendations are provided on labels and data sheets. Remember to pay particular attention to drying times and overcoating intervals.

Step 3: Undercoating

Primed or previously painted surfaces should be undercoated. An undercoat will provide additional depth of colour and improve the durability and film build of the overall paint system. International offers two undercoats for use with its finishes range.

Step 4: Application

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

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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