My advice would be to start with a smallish straight edge like a 2"x10" with 1/4" etched lines in it, and 1/4" thick of course, and see how you do with it. Anything larger is difficult to get onto controlling at first. I bought a bunch before I got proficient that I find I don't bother using. But I love and use my straight edge all the time, on my DSM, my Sweet 16 sit down and now my Longarm. A must have ruler! IMHO
