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 consider employing a professional antifouling paint remover who will use equipment that’s not suitable for a DIY boater.
Before starting your preparatory work:
Mask off areas to be stripped. Complete a high-pressure fresh water wash to remove loose antifouling. All residue and wash water should be contained and disposed of according to local legislation.
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 washed down well with either fresh water or water mixed with liquid detergent. Allow to dry completely before you start painting.
We'll help you calculate how much paint is needed.
Full bodied craft
Fin keeled racing craft
Medium draft racing craft
1 x LWL x (B+D) = Underwater Area (m2)
0.5 x LWL x (B+D) = Underwater Area (m2)
0.75 x LWL x (B+D) = Underwater Area (m2)
LOA = Length Overall
LWL = Length Waterline
B = Beam
D = Draft
F = Freeboard
Recommended no. of coats: ?
If you put less than the minimum recommended numbers of coats, it may affect the performance of the coating.
To paint a ? x ? x ? ??, with ? coats
You'll need ? litres of
Warning that this tool is an estimator onlyView product
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