They are very pretty, I’ve never dipped into polyurethane, it would be a little difficult with furniture ha ha. Do you use oil or water-based polyurethane?.
I always use Johnstons water-based it’s about £30 for 2 1/2 L, dries really quickly and tough as old boots whilst being the opposite of treacly. Ian
Having not much success on the above information l went a different route.
I produced these which were commissions for local people.
This was using CA glue to give me the hard wearing high sheen finish on a waterslide decal. It works absolutely great and the finished item is stunning.