Bottom Painting

The exterior of the hull was always going to be painted white. We used an automotive two-pack paint by Dupont. This meant I had to learn how to spray paint really quickly. I had some guidance from my brother Andrew who has done a lot more of this than I have on numerous car projects. A spray gun was purchased as was a good quality face mask with the correct canisters for both dust and spray paint.

Sadly there are not many photos of this stage. A workshop full of spray paint is no place for a camera!

Here is the hull after sanding is for ages to try to get it as smooth as possible:

Left side:

 Right side:

 First a two-pack under coat was used and a can of black spray used to mark the undercoat so that I could see all the highs and lows when sanding. The under coat was sanded using an orbital sander and 120 grit paper.

Here is what it looks like with the under coat and then the black “guide coat”. See I’m learning all these new words to do with spray painting.

Here is what is looks like after some sanding. You can see where I have rubbed right through the undercoat down to the epoxy underneath. More under coat is now required to fill the low spots. I went through about two litres of undercoat.

Here is the boat outside after applying the two pack finish coat. There were a few runs that needed to be wet sanded off with 600 and 800 paper on a block. Perhaps my technique needs improving a bit?

After wet sanding the runs and then buffing the hull it looks great – but not for long…

I did end up re-spraying both sides of the boat and the transom! When the deck is attached the instructions call for the plywood decking to be glassed to the sides. Of course if you have painted the sides then you need to grind back the paint and then glass a strip of fiberglass along the junction between the sheer and the side.

This destroys the paint on the side when you grind it away the needs much fixing. After putting on the top, grinding back the paint in the top three or so inches of the side and glassing on a strip to cover the junction I found that I could not match the paint very well and I ended up completely re-spraying both sides.

I also re-sprayed the transom and there were a couple of spots that I was not happy with anyway.

I think there is a lesson to be learnt here – don’t spray the bottom (and sides) until you are sure nothing else needs to be stuck to it. Two-pack paint is very expensive and the less time spent with it the better.