Re: Pulled Frame Builder Hive.
Every week, pull frames of sealed brood from the bottom box and move above the excluder, and replace those with foundation into the bottom box to be drawn. Checkerboard the foundation frames into the outsides of the bottom box. Bees will more readily draw in the brood nest any foundation slipped in to "fix" the open space problem in the nest. Keep feeder on like you said. This also is a method of reducing chances of swarming as it gives them space to work on in the broodnest.
But here's the thing, the easiest way to get comb drawn is to capture swarms on foundation frames ONLY. The bees in swarms have full bellies ready to draw wax where they setup home in the new location. If you give them even one drawn frame, they empty their bellies into the drawn comb and don't start drawing wax so well. So, capture swarms on foundation frames only and give them a feeder to keep them drawing wax.
20+ years with bees and still learning. Currently near Marysville, CA, 95901