So why the graffiti attack with the mat black spray paint? Well the answer lies in how you achieve a picture perfect finish to the gel coat repair. Here is the spray can job.
You can just make out the brush marks from some of the layers of gelcoat. And here is the same area after a bit of work with wet and dry paper, Grade 320.
Wet and dry sanding
What you can see is the ‘high spots’ being removed by the sanding and the low spots or troughs showing up in relief due to the shadow effect of the remaining black paint. Incidently wet and dry emery paper comes in different grades, the higher the grade number the finer the surface on the paper. So the above first sanding was done with Grade 320 before moving to a finer Grade 600. I also use a foam sanding block to rap the paper round which helped ‘mould’ the sanding action to the curvature of the hull. Here is the next stage as the work with the 600 Grade progressed.
And the rubbing continued until all the paint is gone, I used 1200 Grade for the final sanding down. Any paint on areas that did not need sanding was removed with a rag and some acetone. Incidentally it is important to only use a white rag or cloth.
The finish was achieved with Farecla G3 Liquid rubbing compound followed by a final polish with finishing compound.
The end result? Picture perfect.
All in all I learned a great deal about gelcoat repairs and owe John Stirling of Port Bannatyne boat yard a huge thanks for his time and patience.If you don’t fancy doing your own they charge £30 an hour and do a superb job. You can contact them here:
|Port Bannatyne Boatyard 73 Marine Road, Isle Of Bute PA20 0LT