Quote Originally Posted by myxpykalix View Post
Ok it's been at least 20 years since i had to do this last and frankly i have forgotten how to compensate for the differences so i need your advice.
I am putting up trim along the base of the staircase along a sheetrock wall with a 3.5" wide baseboard with a trim cap on top. (i'm using flat wood, what you see is scrap used to get my angles correct.)

It is a 40 degree angle where the two meet but by butting them up together you see the height difference? My vague recollection was somehow you split the difference and cut both at an angle and the joint is not a 90 degree straight up and down joint. how do i do this?
I'll either help or look like a fool for not explaining this well.

First you need to figure out the angle. For discussions sake that looks like a 45* angle. So you need a 22.5*, or half, angle to properly mate your joint. Get that protractor out. Or a great shortcut, should you find yourself sans protractor, put a piece of wide tape or paper on the proposed angle. Mark the angle by creasing the paper or marking the tape. Then lay the paper or tape on your miter saw and read the angle off the bed. Once you know the angle divide by two and viola. Works for me when I am trimming boat interiors.