Marks example shows the reason (geometric interpretations). It also explains why a 5 pitch is so close to the 22.5 degrees(22.6214). Thank you much. Now I need to fool around with a compass and a square to iron out the wrinkles. I have always only used the square for joinery and for the most part stayed away from the degrees, the occasional folded kernel and compass/dividers has gotten me through a few hips and valleys. I find dividers to be quite handy at times. Tim
