Warning: a cabinetmaker in Tulsa told me to stop sanding past 180 on face frames, and it took me 4 kitchens to get it
I used to take every face frame up to 320 grit because it felt smoother and I figured smoother meant better, until a guy named Daryl in Tulsa watched me do it and asked why I was polishing wood like a car bumper. He said lacquer needs a little tooth to bite into, and I quit doing it on the next 4 kitchens, and the finish stopped flaking at the stile joints within a year. So is 180 the real cutoff for you all, or does it change with what you're spraying?