Blasting and Sanding: Removing Old Paint Correctly

Over the years antifouling and paint layers build up; new paint no longer bonds well and the surface roughens. At this point old layers must be removed. The right method depends on the boat's surface and condition.

Methods

• Mechanical sanding: controlled but slow; suited to small areas.
• Grit blasting: fast and effective but aggressive; high risk of thinning the gelcoat, needs experience.
• Soda blasting: bicarbonate-based, gentler; harms the gelcoat less, often preferred for fibreglass.
• Chemical stripper: effective on certain paints; needs environmental and safety precautions.

Gelcoat safety

On a fibreglass boat, the biggest risk is thinning or breaching the gelcoat during removal. So method and pressure must be set to protect the surface. The aim is to remove the paint, not the gelcoat.

Afterwards

The clean surface gets proper surface prep and primer; then paint/antifouling is renewed. If osmosis is suspected, this stage is also a chance for a moisture check.

We remove old paint without harming the gelcoat under our painting service.