Chance

Actually the inner line that represents the depth of the dado is the same as the bulkhead edge. The bottom of the dado is what will bear on the bulkhead edge so that is the first line and it matches the edge of the bulkhead. Then you could use a compass to get the other lines parallel to the bulk head line but I have always found that difficult to do. So I use a small 6" steel scale that is divided up into 32nds of an inch and make small pencil lines the correct distance from the original line every half inch or so apart in the area of the curve and then just connect the lines. For me it is just easier.