My wife found a great deal on a Trinity College TM-275 Celtic Mandola. I believe the flat top, flat back, a oval tone hole are what make it Celtic. This Mandola has a 17-inch scale (the distance from bridge to nut), and I’m going to tune it to GDAD (G2-D4), just like my Bouzouki.
The strings gauges I’m going to try first are 19-30-46-64. With the StringJoy Nickel Wound strings, that gives me string tensions of 22.7, 20.8, 25.9, 24.0 pounds, for a total neck tension of 184.8 pounds.
I’m seeing now I should have gone with 34 on the third course, for a tension of 26.7. Darn it.
I’ll update this blog post with my findings, I hope. I may have to make a new nut and bridge.