Mailport: February 2013
Your tests of paints and varnishes are very helpful, but you omitted testing an important coating quality: flexibility. A brittle finish may be more durable on a single piece of wood, but will it survive movement across a joint without cracking and allowing the ingress of water? Considering that wooden-boat owners purchase a disproportionate quantity of this goo, and that all wooden boats have joints that need a protective and durable coating, this is a critical attribute for both varnish and paint.
Secondly, my current favorite single-part varnish is Awlspar, which unfortunately was not in your most recent tests. I have found it substantially more durable than the other products in your tests; it brushes well and is fairly flexible.
We’ve actually tested the Awlspar varnish in the past (PS, Nov. 15, 2001), and our results mirrored your experience. It wasn’t the top pick, but it was in the winner’s circle with good gloss and color retention.
In regards to coating flexibility: Most of our wood-finish reviews have been based on exposure tests and focused on durability and longevity. But a flexibility test is an interesting prospect; we’ll try to revise the test protocol for the next round of wood finish testing. In general, two-part varnishes will be less flexible than one-part varnishes or alternatives like Cetol, and most manufacturers will offer data on this.
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