You don't need "saw slots" like those already in place.  You can use a triangular needle file to make "slots" just a bit deeper than the diameter of the strings.

Sweet brother, nice dulcimer

Thanks, Ken. Never considered a non-equidistant string arrangement for noters. Yes, new slots are in my future, but in the meantime, I'll have to break out my noter.

Action height is an easy fix -- a nickel, a dime and sandpaper will do the trick.

Never see string spacing quite like that...  Almost a 4 string with doubled bass and melody courses.  If you are a chord-melody style player you may want to re-cut some slots to get a spacing that will work for you.  As a noter-drone players, I would shift everything except the melody couplet as far out as it will go, so there is room for my noter.

My brother purchased this dulcimer online. The gentleman who sold it said it was his son's mother-in-law's who had recently passed, but it had hung on the wall and nobody ever saw her play it. He also has a sitar of hers that was in terrible shape. :-) My brother knew I liked dulcimers and thought the instrument was in good shape and the soundboard was attractive. Also, it was built the same year as my daughter was born, so having an instrument as old his niece was fun. It had one string. So I added three more strings, but the slots on the bridge and nut were not where I would expect. I was expecting a slot in the center in the fretboard for the middle string. Any ideas on the slot configurations? Also, the action is a bit high up the fret board. I do like it's sound.

When I opened the case it still had the original pamphlet. I've attached some pictures. Anyway, my brother is really cool and I can't wait to get the modifications made. If anybody has any additions insights to this dulcimer maker or his instruments, please share.

Thank you,

Tom

updated by @tom-olson: 10/27/19 12:02:25PM