The first hive I built was a tbh, it has frames. I took 2x4's cut them at an angle, turned it around ran it back across table saw to get a wedge or point. Cut to length, cut a knoch to rest on sides of hive, added sides and bottom to frame. My top bars are 1 1/2" wide, inside of frame is 17" at top, 11" down the sides, and 9" across bottom. Most of my langstroth hives are foundationless also. No problem, keep a check that they are building straight, if you catch is quickly you can just push it a little so it is straight. Good luck with your bees. Hope this helps.