Expert advice

How do I remove aged finishes?

When preparing a surface previously painted with a finish or varnish scheme it may be necessary to remove the aged product, back to bare substrate. This will be required if the existing coating is in poor condition or if you’re intending to apply a two-part product onto a surface previously painted with a one-part finish or varnish.

Step 1: Health and Safety

Before commencing 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 dust mask.

Step 2:

Remove any sections of the aged finish or varnish that are already loose, flaking or detached using a scraper – rounding the ends of the scraper before commencing will avoid gouging the surface, resulting in unnecessary repairs.

Step 3:

After removing the old finish clean the surface using Fiberglass Surface Prep YMA601, Fiberglass Solvent Wash 202 or Special Thinner 216. Follow instructions on the product label.

Step 4:

Abrade using 60-120 grit paper, removing as much of the paint or varnish as possible.

Step 5:

Prepare according to substrate, following bare substrate preparation guidelines.

“Hints to help you achieve a perfect finish.”

  • We do not recommend using a chemical paint stripper when working with fiberglass, unless the product has been specifically approved for this purpose, as this may cause damage to the substrate.  
  • Varnishing is best achieved on warm, dry mornings – cold weather slows drying and dampness spoils the gloss.
  • When working with wood, always work in the direction of the grain, whether sanding or applying varnish. This will avoid scratches that can still show through, even after many coats of paint or varnish.

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