Just how much varnish does it take to create ‘that’ look.
A painter had just lovingly finished the topcoat of paint on a wooden hull, and was standing back to admire the finish when a passer-by brushed against the hull leaving a long, ugly smear. The painter was horrified. “Oy!” he cried. “You’ve just rubbed your sleeve on my paintwork!” The man stopped, and seeing the long white smear on his elbow, said “Oh, not to worry – it’s an old jacket…”
The glamorous set
I’ve just come back from the Riva boatyard at Sarnico, nestled beside the beautiful Lake Iseo in northern Italy. The mahogany Riva launches were made famous by the likes of Brigitte Bardot, Elizabeth Taylor and Peter Sellers, to name just a handful of celebrities who bought one.
This was mainly because the company’s director during the 50s and 60s, Carlo Riva, aimed to make his boats the alter ego of the most stylish cars of the era, a sort of Lamborghini on the water. The boast became a ‘must have’ item for the great and the good.
Key to this was varnish like glass, but as anyone trying for the perfect finish knows, it isn’t easy. That gloss surface seems to hoover up every nanogram of dust in the air, and then bloom like orange peel. After a season or two it will start to split and crack, and then peel happily.
So how does Riva get such amazing results, and how do they stay in such good condition?
The secret, I discovered as I watched the craftsmen work, is to apply no less than twenty coats. You have to lay down the first ten by hand, sanding down between each one, but not with sandpaper – oh no. The Riva team uses a mesh-like abrasive disc on a low-revving Rupes sanding machine.
The P80 disc just gently skims the surface, leaving no gouge marks as sandpaper does, but simply knocking off the tops of the dust particles. (The team at Hillyard’s would use fine wire wool on the last few coats to achieve a similar finish).
No less than twenty coats
The last ten coats are applied by spray in a climate-controlled booth, something beyond the average DIY enthusiast, but a lot can be done to mimic the conditions. A heavily soaked floor to trap dust, an extractor fan, and soft sponge brushes can all help to get near the perfect gloss finish, given enough time and patience.
As for preventing the varnish from lifting later, preparation of the surface is critical. On the beautiful rigatino (mahogany inlaid with maple) decks, the first job is to painstakingly run varnish into the minute cracks between the two strips of wood.
This can take hours and is murder on your back, but the varnish acts as a seal and locks the wood together, purging any moisture or trapped air that would otherwise undermine the varnish from beneath.
On the large mahogany rubbing strips around the transom, a groove is introduced at the corners. This acts as an expansion strip for the wood, and prevents the varnish from splitting due to movement.
The most coats I have ever applied to a boat is six, with the first one thinned to 50% with the appropriate solvent.
Maybe I need to take a leaf out of the Riva book, and go for twenty in a dust-free environment, because the final result is truly worthy of the stars.
Jake Kavanagh, marine jounalist
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