Varnishing the deck of a 1929 wooden yacht: why it's redone every year
How the exterior brightwork of a classic teak-and-oak boat is maintained. The product used, the number of coats, drying times, cost. The hands-on experience of ten years restoring the Davia.
By Bruno Van Hemelryck, president of the Association Davia
When I say « 2,400 hours of work since 2014 », half of that time has gone on varnish. Not the hull, not the engines: the varnish. And every year, we put on another coat. Here is why, and exactly how we go about it on the Davia.
The timber of a 1929 yacht
The Davia's hull is of oak, iroko and Maine pine. The covering boards, the wheelhouse and the exterior joinery are teak. Teak is ideal for the marine environment: dense, oily, naturally rot-resistant. But it is also sensitive to UV, and without protection it greys within a few months, then cracks.
On a classic boat, varnish is not there to decorate. It is there to protect the wood from water, salt, sun and the freeze-thaw cycles. An unvarnished deck, even in teak, lasts 5 to 10 years depending on the climate. A well-varnished deck, maintained every year, can last a century, like the Davia's.
The damage before work began
When I took the boat on in 2014, the exterior varnish had been applied in 2015 by Francis Ruffenach before the sale. A single coat, on a poorly sanded surface. Aesthetically it was presentable. Technically, it did not last two years.
By 2017 I had to redo everything. I worked at the Evans boatyard in Migennes, under the eye of Simon Evans, himself an enthusiast of the Dunkirk boats. He gave me the right method.
The method, step by step
1. Stripping and sanding. The old varnish is removed with a heat gun (no chemical stripper, which attacks the wood). Then we sand with 80, 120, 180, 240 grit paper. It is slow. On the Davia's aft saloon (around 8 m²), reckon on 3 to 4 days.
2. Inspecting the wood. We look for cracks, rotten areas, open seams. All of it is repaired before varnishing. On a 97-year-old boat, there is always something to put right.
3. A heavily thinned first coat. The marine varnish (I use Epifanes Clear Gloss, the reference for classic boats in Europe) is thinned 50% with the specific Epifanes thinner. This first coat penetrates the wood and acts as a primer.
4. Successive coats. Between 6 and 10 coats in total, each lightly sanded with 320 grit before the next. The drying time between two coats: 24 hours minimum at 20°C, far longer if the humidity is above 70%.
5. Finishing. The final two coats go on undiluted, with a flat brush or a tipping-off brush. That is where the finish is won or lost. A botched coat means starting again.
The figures
On the Davia, a full cycle of redoing the deck represents:
- 120 to 160 hours of work depending on the areas involved
- 8 to 10 litres of Epifanes varnish (reckon on €80 a litre)
- 3 to 4 calendar weeks, allowing for the weather
- A range of €1,200 to €1,800 per cycle if you buy all the products
Each year, I apply a maintenance coat on the most exposed areas (aft deck, wheelhouse panels). Reckon on 20 to 30 hours and €200 of products. Every 3 or 4 years, I redo a complete area (stripping, sanding, rebuilding the coats). And every 7 to 10 years, we redo the lot.
Why not a modern product
I am often asked about epoxy resins, two-part deck sealers, « long-lasting » UV protections sold as a miracle solution. Short answer: on a classic boat, no.
An epoxy resin creates a rigid film that cracks with the movement of the wood and seeps in underneath. A traditional marine varnish is flexible, it moves with the wood. When it wears, you sand and put on another coat. With a rigid resin, when it lets go, you have to strip everything with aggressive thinners, and you damage the wood beneath.
The boats of the Association of Dunkirk Little Ships all have one thing in common: their owners use traditional marine varnishes. It is not out of nostalgia, it is because these products have been working for 100 years on these very same boats.
What it gives
Today, the Davia's deck and exterior joinery are in good general condition. The major job of completely redoing the deck and bringing back the original teak is planned for the next two years, in preparation for the 2029 centenary.
It is for that job, among others, that the association is seeking donations. A new teak deck over 50 ft (15 m) costs more than a fully rebuilt engine.
More from the log
October 2014: under a tarpaulin in Villeneuve-sur-Yonne, I found a Dunkirk Little Ship
How Bruno Van Hemelryck discovered the Davia, a 1929 Scottish yacht lying asleep under a builder's tarpaulin in the port of Villeneuve-sur-Yonne, and why he gave everything up to save her.
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What is a Dunkirk Little Ship? History, numbers and recognition
The 700 British civilian boats that evacuated 338,226 Allied soldiers from Dunkirk in May to June 1940. Fewer than 50 survive worldwide. The Davia is the only one over 50 ft (15 m) still in France.
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