Using crossbeams will add stability to the arbour. To make the first one, take a piece of the 985mm pine, measure and mark 30mm down each end, then cut at a 45-degree angle from the mark toward the centre of the beam. Along the edge of the timber you've just cut, measure, mark and square off pencil lines at 60mm then 106mm – this is where we're going to notch out a joint. Set your drop saw to a 50mm cut depth and make a series of cuts between the two pencil lines. Using a hammer and chisel, check-out the waste wood that remains. Make this check-out at the other end of the crossbeam. Then repeat this process to make the four other beams.