THE formula, which, at 3:00 a.m., was to be published, but only got partially published:
I started with a ninety degree angle, since it was the easiest to come by. All I had to do was use an L square, or measure 3,4 then 5 feet (measure three feet, turn, measure four feet, turn the same way and line the tape with where I started).
Once I had a ninety degree angle, I could get started, or go equal distance on each leg, measure the distance between the two points and split it in half for forty-five degrees.
Depending on how big the item was going to be, I could use eighth of an inch, quarters of an inch, halves or even larger fractions or whole numbers to represent each degree mark.
We know the entire angle is ninety degrees, so, if we use the ninety degree angle, we will need to use ninety of the chosen increments. If we used the forty-five degree angle, it would, of course, require we use forty-five of them.
Staying with the forty-five degree angle and choosing 1/8” increments, I will need a measurement 45/8th’s, (5”5/8”), which will be measured across the angle from two points that are an equal distance up the two legs of the 45.
It may take a couple runs, moving the line between the two legs up or down them, before you find the position which gives you your 5-5/8” distance.
Once you find the points that will give you the 5-5/8” distance, you can double it, rather than resort to trial and error again. You could also make a chart, which I will, giving the measurements for extended points.
With your line ran between the two legs, mark eight inch increments on it for the forty-five degree marks. Mark critical positions, such as 90, 72, 60, 45, 30 and 22-1/2 degrees for easy location in the future.
Using this, you can mark any angle accurately. I found this useful for setting up to run 2x’s for ten degree angle cuts.