Monday, October 27, 2014

Hull Painting

                                 Hull Painting above and below the water line.

Although it looks like most of the below described work was done this year it actually has been taken place over several years due to the extensive repairs onto the hull and other maintenance which I thought was required before even starting on the painting of the hull.
Also since the hull is made from wood the paint choice might look easy but it took some time to decide, lost of information from the internet and specialist I know through my daily work before a final decision was made for in my opinion the best paint for the boat.
I have chosen to go with International paint system.
Above the water line with Yacht primer, Pre Cote and Toplac, below the water line Primocon as primer and a later to decide anti fouling paint.

As can be seen from the next picture the paint was in such a condition that I took the decision to completely strip all the paint of the boat and start all over with a new paint system.

First step was to remove all algae and shells which had grown over the years onto the hull.

During the course of the hull repairs paint was removed where required and where old and new wood were joining the hull was sanded smooth.
After sanding the wood was protected with several coats of virgin linseed oil.

At a certain stage of above mentioned repairs the complete hull above the water line was removed from paint, scraping and sanded smooth followed by treating with linseed oil.

This year the plan was to paint the above and under water line, more or less the complete hull.
First step was to remove the linseed oil from the hull and sand the hull again smooth before the primer would be applied. This was not as easy I was hoping for since the linseed oil although it entered the wood also build up a layer on the outside of the wood, could not be easily removed.
Sanding was not possible since the paper was full within seconds. Only thing left was to scrape the hull clean again from the applied linseed oil.

After all linseed oil was removed the hull was sanded smooth.
Hull was then cleaned from dust and degreased with acetone followed by the first layer of yacht primer. The first layer was diluted with thinner to make sure that it would impregnate the wood.

After the first coat of primer one could also good see the deficiencies in the hull which are not so clear after sanding.

Those were filled with International Watertite filler, the spaces between the planks were not filled those will close naturally when the boat gets into the water.

All was sanded again to my satisfaction.

Than another 3 coats of yacht primes was applied as per manufacturer’s recommendations.
The following step was to apply 2 coats of Pre cote an intermediate paint between the primer and the final coat.

Before the final paint was applied the surface was lightly sanded with grid 320 to create a smooth surface. The final paint I used is TopLac white, 3 layers were applied.       


Before the boat will be launched another two layers of Top Coat will be applied, of course after first sanding and degreasing the present installed finished coat of paint.

The below the water line anti fouling was in reasonable condition but I did not know which paint system has been used therefore all paint needed to be removed.
First stage was to remove the growth on the hull.

Then from the complete hull the anti-fouling paint was removed with scarper and hot air gun which mainly has been done by my wife.
As can be seen, red paint, which I presume is the old fashioned wood protecting primer, most likely with led, I left on the wood since it was in a good condition.

After scraping came sanding, since it is under the water line the surface was sanded but not till a very fine grid, last paper used was with grid 180. For better access to the hull the propellers with shafts were removed as well the rudders. Both systems require attention as well which will be worked on in 2015.

First coat of Primacon was applied which was diluted with thinner as per manufacturers recommendations.  Than the small holes, mainly where the plugs for the rivets were inserted were filled with two component filler. I have used the International filler to make sure that there would be a good bonding between their materials, filler and paint, this way preventing the chance that there would be over time separation between the two.
Before the boat will receive its antifouling paint the hull, below the water line will be lightly sanded again and two more coats of Primacon will be added before the actual anti fouling is applied.

After all was sanded smooth 3 more coats of Primacon were added. Following pictures show the present condition of the boat.

One of the reasons I choose to use International paint is that the primer for the antifouling can remain for a long time unprotected and it is not required to apply the actual anti fouling paint within certain months or weeks onto the primer. This is required for most of the competitions antifouling paints, primer cannot be unlimited exposed to air.


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