Originally Posted by Pblais
Hard finishes usually require sanding between coats. Cetol and many others do not if applied consecutively without prolonged exposure to the weather
Yes, and two part PU's dont require sanding between coats if you recoat within 48 hours. But you still might want to sand between coats. If anything because...
1. Following the wet edge over an unsanded coat can be a pain. Especially if it is very glossy. Increases chances of holidays.
2. Unless you have PERFECT brushing technique, you are going to have to sand out the brush strokes and/or the occasional run between coats.
Again, if you want a great finish, you should sand.
I tried Epifanes High-Build varnish, which could be recoated without sanding within 24-48 hours. But, because it was saturated with more solids than the traditional varnish, getting and even application was difficult and you wanted to sand after two to three coats anyway.
Then the trick becomes in the sanding technique as you must be careful not to remove too much or for sure you will get an uneven overall coating.
There is no silver bullet.