If you're dealing with inside corners, coping will work for any corners that aren't radically different from 90°. If they are quite a lot different, more than likely they are 45° corners especially if they are different in pairs. It might be worth a try with a couple of pieces of scrap to cut them 22.5° and see how they fit. If your corners are completely different you still have several options. The easiest probably is to invest in an angle finder, basically an adjustable protracter with a scale on it. Another option would be to use a T-bevel, sometimes called a sliding T-bevel. This is basically a tool with two leaves that can be loosened and/or tightened. Loosen the wingnut, lay it in or on the corner and tighten the wingnut. That will give you the angle of the corner. You need to set your saw at half of that angle though. That is easy to find, but their are a few steps to go through to do it. 1. Transfer the angle to a piece of paper or scrap. 2. Call one leg of the angle "A" one leg "B" and where they intersect or make a point "AB" 3. Place one leg of a compass or dividers on "AB" 4. Scribe an arc a few inches away from "AB" on line "A" and line "B" 5. Scribe an arc from each of these intersections so they cross to form an X 6. Draw a line from "AB" through this X and that will be your saw setting. There is a simple illustration of this at http://www2.fwi.com/~krumy/angle/angle.htm Steve K.