Re: epoxy

Posted by Laszlo on Mar 2, 2007

Maybe. I don't think S3 will blush badly enough (at least I've never seen it do so) that you'd actually see it. You might be able to feel it as a greasy film. But here's the thing - blush is just unreacted amines migrating through uncured epoxy. They won't form the immobile film until the epoxy has cured to where it's impermeable. So if you only wait for the epoxy to cure to where it won't run anymore, to where the tackiness just disappears, it's still incompletely cured and you can put on another layer without having to wash or sand. If you wait longer than this, you need to clean the surface.

The trick is getting the exact timing. If you're not sure, go ahead and wash. My rule of thumb is that if it's 24 hours or less I don't wash. Longer than that I do wash. After 3 days in the summer I give it a light sanding, too. That's based on information from System 3's Epoxy Book (downloadable from their site).

Hope this helps. For other readers, this advice is for System 3 marine epoxy only. It may work for other epoxies, too, but I certainly won't guarantee that.


In Response to: Re: epoxy by Jeremy on Mar 1, 2007