Hi, amateur here finding F&B paint hard going. I have read the long post by Andy from 2012 on their primers and undercoats, and concluded I was best to stick with F&B’s own undercoat for a Modern Eggshell finish on a couple of doors.
One target door had a variety of previous coats so flatted down properly, washed with sugar soap, and painted on the mid-tone u/coat, working quickly and laying off carefully because it was hot, hot, hot and the paint was going off quick, quick, quick.
The result was really disappointing, yes coverage OK but heavy brush marks that needed flatting again. To add to the misery, the u/coat is very resistant to flatting, rapidly clogging sandpaper of whatever grade.
I have never had to work so hard to get a decent finish with the Dulux products I generally use, not even using their quick-dry paints outdoors on a hot day, where speed is of the essence.
Would I have been better to use an aluminum primer, as the pro decorator did on the previous work that I am attempting to match? That stuff stinks like mad but it did the job all right without needing lots of extra work.