February 18, 2015 Hours spent building to date: 707
The material is usually fiberglass and the process is called “glassing.” But Tardis is going to have a covering in keeping with her science-fiction name: Xynole.
Xynole is a polyester cloth — basically the same as stuff as a made-in-Malaysia golf shirt, but modified to make an incredibly tough, abrasion-resistant covering. Xynole has a big following on the WoodenBoat Forum, and I used it on the Jericho Bay. I had to repair a 10-inch area on the transom, and it took 10 minutes of sanding with 40 grit paper to even make a dent.
What I like best about Xynole versus fiberglass is that it really soaks up epoxy. I felt on the fiberglass chine band that we were having to force every drop of epoxy through the glass and onto the wood, and in the process it dripped and ran all over. Xynole just sits there and drinks epoxy and produces a clean, even surface.
So why doesn’t everyone use Xynole? Because it really soaks up epoxy. It takes a lot more work to fill the cloth and make an even surface, usually five coats to fill the weave versus three for glass. And the first coat is a killer in terms of expense — I think Ray and I used almost a gallon and a half today to do a 10-foot strip on one side of the boat. But the effect is basically an epoxy shell encasing the boat, which I think is worth it.
To cut down on the work some, I added 410 Microlight filler to the second coat at about 1 teaspoon of microballons for every pump of epoxy resin. It was still easy to roll on, and I like the surface it produces. Ray and I did two strips today in just over two hours. Working by myself, carrying container after container of epoxy up onto the boat and spreading it evenly bit by bit into the cloth, I can usually do one strip in that much time after which I am exhausted.
The ultra-cold weather we’re having here actually helps with the process. I put on a coat in the late afternoon at about 66 degrees, then knock the temperature down to 50 overnight to retard the cure time. So when I come back in the morning I can apply the next coat to the “green” epoxy and get a strong chemical bond without sanding, then another coat in the afternoon, turn down the heat, etc.