Hopefully, these drawings will simplify the witches cut layout for Square Tail Fascia.
These drawings are for an unequal pitch roof, but the layout technique is the same for equal and unequal pitched roofs. For unequal pitched roofs, repeat these steps on the other side of the hip rafter material and use the adjacent side common roof pitch in step 4.
Step 2: Draw the Hip Rafter Level Line.
Step 3: Draw the Hip Rafter Plumb Line @ the End of Hip Rafter Level Line.
Step 4: Draw a line using the Common Rafter Pitch that intersects @ A.
Step 6: Draw a Line from D to C . The Angle ADC = Hip Rafter Miter Angle for the Witches Cut.
Step 7: Draw the Hip Rafter Backing Depth Line on the side of the hip rafter.
Step 8: Shift the Miter Line D-C to intersect at point G. These lines must intersect, 1: Hip Rafter Level Line, 2: Hip Rafter Backing Depth Line, and 3: Hip Rafter Miter Line for the Witches Cut.
Step 9: Draw the Center Line of Hip Rafter on the top edge. Draw the Back Bevel Line.