Yeah, we did that trick a lot when doing the brightwork on boats we built and refurbed. West System 207 as I recall (but don't quote me on the number). Worked fine, right up until we got a couple boats back 3-4 years later for brightwork rehab. (Nothing will withstand the harsh salt environment perfectly forever and ever, 3-4 years is normal for a boat to need re-varnishing. Some people do it every year.) What happened was the epoxy underlayment made stripping back to bare wood a lot harder. I don't personally know anybody around town here who still uses epoxy as a base coat, but I'm sure there are those who do.
As tough and impermeable as epoxy is, it has like zero UV resistance. That's why you gotta put a bunch of good varnish over top of it. (By good, I'm talking stuff with a high solids content. The best IMO is Epifane's but it's OMG expensive.)
Last edited by gnoahhh; 06/30/19.
