If your existing antifouling is in poor condition, we strongly recommend removing it completely before repainting. There are two methods outlined below, but you could also consider employing a professional antifouling paint remover who will use equipment that’s not suitable for a DIY boater.
Before starting your preparatory work, please ensure the area you are working in is adequately ventilated. Ensure you are wearing the correct Personal Protective Equipment (PPE). We recommend safety spectacles, goggles or visors, nitrile rubber gloves, overalls (ensuring skin is not exposed) and a solvent mask or a respirator (if working on larger areas or in confined spaces). Depending on where you are re-antifouling, you may need to use bunds to collect liquid and solid wastes to prevent them from entering waterways or surrounding ground. You may also need to use suitable tenting to protect those not on the job. Make sure you understand and follow all local regulations.
Complete a high pressure fresh water wash to remove loose antifouling. Ensure all residue and wash water is contained and disposed of according to local legislation. Mask off areas to be stripped.
Removal Method 1: Sanding
Using 80 grit coarse abrasive paper, wet sand your boat to reach the desired level or when all of the antifouling has been removed. Take care that the primer under the antifouling is not damaged too severely and ensure you don’t sand it back to the substrate. With GRP vessels the coarse abrasive paper may scratch and damage the surface.
Removal Method 2 - Chemical stripper
Use a suitable chemical stripper and follow the instructions very carefully. Ensure the primer under the antifouling is not damaged too severely. Be very careful to check that the chemical stripper is suitable for use on GRP surfaces. Some types may soften and affect the GRP surface, even if coated with primer. For best results, work on a small area at a time.
Ensure surface is well washed down with either fresh water or water mixed with liquid detergent. Allow to dry completely before you start painting.
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