Friday, 19 July 2013

Painting a GRP Boat



Not a cloud in the sky - well almost!
Life here is a bit crazy at the moment. After suffering a prolonged and hard winter with virtually no spring, we
are now sweltering in a heat wave which brings the daytime temperatures up to and beyond 40 degrees in the sunshine of the courtyard and 24Degrees C indoors. I’m sure you could cook an egg on the hot GRP cabin top in the boatyard. Not ideal weather for climbing into the bilges to clean and repaint them. Still it has to be done, pushing my way in there from the cabin and painting in some places using a brush taped to a boathook.

After that, there was no excuse anymore for avoiding getting on with painting the cockpit. I’ll tell you how that went on in a later post but meanwhile take a look at the tools I’ve been using.

First a Bosch Genesis GMT15A Multi-Purpose Oscillating Tool . This has probably been my most useful tool for getting the gelcoat clean, smooth and ready for painting. I burned out two other sanders working on my house so I decided to pay real money for real quality this time and – well, so far so good.
One slight complaint is that the pad on which the sandpaper is supposed to sit can become clogged very quickly – replacement pads cost me up to 9E and I’m currently on my third. The second one lasted no time at all, due, I think, to the fact that I stored my sandpaper in the boat cabin and the humidity encouraged the Velcro type substance to become detached from the paper and permanently glued to the pad. Keeping sandpaper bone dry seems to help.

Second – a very old Black and Decker electric drill with a sanding pad attachment. Everything  I read advised against sanding with an electric drill. There were dire warnings about the disks turning too fast, the dangers of gouging out pieces of gelcoat if you aren’t careful – etc – etc. All I can say it – it worked for me, especially on large flat areas and especially on pre-painted areas. The trick seems to be to use both hands to hold the drill, use only one side of the disk avoid all distractions and stick to a relatively gentle grade of sandpaper.

Third a Honda generator. I bought this from a friend for £50 ( 60E?) and so far it hasn’t let me down.

Apart from that, well copious amounts of sandpaper and a sanding block have been required. On the worst areas I used 80 grade, bringing the whole job to 120 grade before painting. Between coats of paint I’ve been using 240 grade to smooth out blemishes and provide a key for the next coat. Paint was International Paints Pre-Kote followed by Toplac from the same manufacturer – more about that next posting.

Finally, I have to pay a special thanks to BB King, Lightning Hopkins, Chris Rea, Muddy Waters and John Lee Hooker. This sanding business is no intellectual challenge – in truth it’s really boring but if you have good music with you then life is tolerable.

Seaward