CUTTING JACK RAFTERS After figuring the first one, it's as easy as measuring, setting your saw to 45 degrees, and cutting. Roof framing is, for most carpenters, a mysterious joining of rafters that-with a little luck-fit the first time. For some, it is a nightmare of frustration. Most of us have no problem with common rafters or an occasional hip or valley rafter, but jacks often seem mind-boggling. The key to understanding all rafters is to think of them in terms of horizontal and vertical coordinates (lengths of run and rise) rather than as the diagonal lengths they really are. They should also be visualized in plan and elevation views. If thought of in these ways, all rafters are quite