Painting Oil Based Doors

[beachside]

I'm painting a few old oil-based doors during the night this week after work. I made the mistake of using water based primer the first time and it flaked so this is how I'm doing it this time...

- apply oil primer - apply water based topcoat

I thought the water based primers were more the norm with the ability to top coat with water or oil based - and most painters seem to still prefer oil based top coat on doors and trims for hardness! You have done the reverse - was the door sanded before the water based primer?