We revarnished (3 coats) some 7 year old woodwork, which is indoors, using Min wax Helmsman varnish. The label says it is "spar urethane"
We noticed that it peels off with the fingernail after drying a couple of days, so stripped it with a plastic scraper.
Result on photo. the varnish file is fairly strong, but adhesions is nil
We do not know what the original varnish is. The builder is long bankrupt, so no info there
We though that at 7 years old, we could put about anything on.

Anybody know what varnish will stick ?