What kind of paints are you using? Since the friul treads are metal, you could bake the paint onto the treads in your oven.
1) Preheat normal (not microwave!) oven to 200 f.
2) Paint the treads.
3) While still wet, put the painted treads in the oven on a piece of wood. Let bake for around seven minutes.
4) Take out and allow to cool. Aerate the oven. (Leave door open and open your window.)
This bakes the paint right into the metal. I've had better luck with oils than with acrylics, but it works ok with acrylics too. Try to do it when your better half will be out for a while, so you can aerate the house. It stinks, and she won't like it going into the oven.