Thanks again, Kevin!
You're not the first to recommend Erlewine's book, so it's in my cart.
I've tried to do truss rod adjustments before, but with limited success. I understand how the rod works, and what the effect of turning the nut is, but when I actually start turning it, I sometimes can't get it to a place where the action can be reasonable without buzzing.
That happened just this week with a guitar that was recently setup by my trusted tech. He suggested I give the nut a turn until the buzz went away. I tried and tried, but just couldn't get it right, so I brought it back to him, and he did it in a matter of seconds.
That's why I thought I might benefit from actually being able to measure how far it's off and how much I've corrected it, at least until I learn to do it by feel like my tech can.
My only reservation about buying the Neck Check is that I have a wide range of scale lengths, not just Fender/Gibson. I'd like to have one tool that would work for everything.
Would the effectiveness of this tool be terribly compromised if the notches were a bit larger to accommodate multiple scale lengths? As long as there was enough metal touching the fretboard between the frets to see a gap, it seems that it wouldn't have to cover the whole space between frets. Or am I not grasping the concept?