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Use Butyl on varnish?
A friend has a lovely wooden boat. We were refinishing the mast and found rot under one of the forestay mounts. It's basically a stainless strap that is screwed and through bolted to the front of the wooden mast. I suggested using Butyl tape to seal it after the repair, as whatever they used before obviously didn't work! I provided a link to this thread. I thought surely, given the tackiness of the tape, it would adhere to varnish. However, he brought up an interesting point.
"I re- read the article on Butyl tape and decided not to use the product because it would be sitting on a newly varnished surface. Varnish off-gasses volatiles for several weeks after it is applied. The volatiles are the thinners we would use for cleaning up the tape residue. The illustrations in the article featured hardware going onto gelcoated surfaces. Bottom line, I was worried about the gap, and the compatibility of the butyl tape and the thinners in the new varnish."
I don't think the 1/8" gap is a problem and have used paint thinner to clean up excess Butyl, but wondered about the off gassing.
Last edited by L124C; 05-18-2011 at 01:42 PM.