I think Dusty is correct. In 1982 Orthey dulcimers came tuned DAA if I remember correctly. The string gauges would be as Dusty mentioned. When people moved to DAd playing, the middle string probably changed to 0.014.
Ken
"The dulcimer sings a sweet song."
With those large diameter string pins.... if you can't find loop-end strings, you can make a loop by running the open end of the string through the ball-end and pulling it up tight.
The other Orthey dulcimers I've seen had VSLs of 27". If yours is close to that, a wound bass string around .024 would probably be right. Middle string perhaps .012 or so and the melody string would depend on your tuning. If you are tuning DAA, then keep a .012 for the melody. If DAd, perhaps .010.
My personal preference would be for slightly heavier strings (.026, .014, .012) but those that I list might be close to standard for that size dulcimer.
And as the image suggests, you will need loop end strings, although if all you can get are ball end, you can always remove the ball manually. Just squeeze them gently with plyers and pop them out of the strings.
