You are all too kind. Actually I am not informed; I just work in a library. And now to business.

A cuatro should truly be tuned BEADG (across the fifth fret). The E's and the A's are octaves apart; the D's and G's are identical. The bass course is a FIFTH interval--someone wiser will tell us what not that is.

My cheating mandolin+bass tuning is CGDAE. Because of the shorter neck, figuring which strings to use was tricky, so here are the diameters Alex settled on after trials--octaves on the bottom three courses.

E: both .33 mm A: both .56 mm D: .91 and .46 G: 1.32 and .66 C: 1.42 and .86

We used D'Addario guitar strings.

I'm glad is someone finds this useful--but under "bowed dulcimers"--I guess that's what I'm learning to call "creep." Should this be re-posted to a "Cuatro" thread?? Thanks, I will consider joining, but I fear this could become addictive.

Chicken Charlie [or whatever type you fancy]