Is there any chance there was blush that wasn't removed from the epoxy on the interior? I understand that can cause the symptoms you described.

Ross

: I am new to the list, but am actually building my forth strip boat. I am
: using a spar urethane that has worked out well in the past. The first coat
: on the outside of the hull dried beautifully. On the inside of the hull it
: remained tacky. I tried extra heat, fan, more time. Made no difference.
: Finally, I scraped it off, and re-did a trial section. It remains tacky. I
: can take the same varnish and do a section that dried previously and it
: will still dry to touch in half an hour. One possibility is that the
: problem originally was related to too low a temp because I work with a
: kerosene heater in a garage, or it could have something to do with the
: epoxy cure. What can I do to get it to dry hard? This is driving me nuts,
: any help would be greatly appreciated