About a cup's worth per every 2-3 hours... it's very slow, but the resulting honey is beautiful, crystal clear.
I like to know how you are using your coffee filter. I've got some honey from a cutout with alot of pollen in it. I'm using a coffee filter in a camping 1 cup holder and I'm only getting 1/4 cup per DAY. I think its the amount of surface area avaiable for flow, as most of the sides touch plastic and doesn't allow flow.