Dan asks "What space do you try for between the top of 1 frame and the bottom of the other one?" Dan This space must be as close as possible to 3/8th of an inch (.95 cm). This 3/8th spacing is referred to as "bee space". At 1/2" bees will build burr comb and at 1/4" bees will fill the space with propolis. (I forget just how well 7/16th or 5/16th will work.) To complicate matters, some US manufacturers place the bee space on the top of the super, others on the bottom, and at least one even "splits the difference" so that there is 3/16th on the top and another 3/16th on the bottom! Quite a problem is created when a super made with the bee space on the bottom is put on top of a super with the bee space on the top. This generates a space of 3/4", sure to be completely filled with burr comb, causing a grand mess when the boxes are split. If those same two supers were reversed, the bees would glue them together so tight that after a season the beekeeper would need a crowbar to split them! So when you hear the US has standardized on Langsforth equipment...hear that as "almost standardized". One thing we all do agree on is that Langsforth's discovery of bee space and its significance is as valid today as it was in the 18th century. Lloyd