Don't know the exact frame you are looking at, but I have an 18" tin lizzie with a 10' frame. The base is about 42" deep, and I have about 2 feet in back, it is really tight, but I don't do pantographs. 3 feet would be much better. With the smaller 18" unit, you can easily pin the quilt to the back rollers from the front. So 3 feet in front, 3 feet in back plus the frame is 9 - 9.5 feet, and you need to get to both sides to raise an lower the rails, so at least 3 feet at one end, and a foot or so at the other so you can reach around. You are looking at 9 by 14 minimum.
Last edited by PaperPrincess; 10-04-2013 at 08:57 AM.