Dwain,

   I moved the nut toward the scroll .12" , set the location of the 6 1/2 fret by using the corresponding note on the middle string.  The strings are 0.12, 0.12, 0.14, 0.12, and 0.24. Even though the measured locations are not exactly according to the fret calculator, it notes true  and checks in tune with harmonics.  It is a very easy playing  instrument with a bold sound.  I do think I will change the middle string to a .016 size, it has a slight twang . That may be caused by slot in the nut or bridge, will check that first.

  All I have been able to find out about Davis dulcimers is what seems to be common info on the internet  and a little info from a man in London who has  at least a few of Bill's dulcimers. 

  Thanks again for your thoughts and directions.  I am a relative newbie to dulcimers, I got my first one about 10 years ago after I retired the second time. I didn't build my first one until I turned 74, am now 81 and have built 131. 

                                Bill R

Good! keep us posted on your work with this instrument. Know anything more about Davis?

Here is a tip on finding out how low to get the saddle:

First check to see that the frets are level. To do that, use a good quality set of machinist squares or combination squares. Choose sizes that will span the frets three at a time. Start with setting the blade of a square across frets 1-2-3 and see if the blade of the square rocks on the 2 fret Check on both ends of the frets and the middle.

If it does, that fret is high. Grasp the dulcimer by the fretboard (being careful not to let fingernails dig into the top!) and lift it slightly off the table so you can hammer the fret without having the top get the force of the blow.

Now give that fret a somewhat ungentle tap and test again. Remove the strings and file the fret down only if you cannot get it better seated. Then check the 2-3-4 fret, and so on up the fretboard, choosing smaller squares so the blade only crosses three frets at a time. If you don't have a square small enough to fit across only three frets at the top end, use a single-edge razor blade for a straight-edge or some other known and trusted straight edge (ground and polished machine lathe tool bits, for instance). I would not trust aluminum bar to be straight for this purpos, due to how it is formed.After you're sure the frets are all level, you're ready to see how low you can get that saddle.

Begin by replacing the saddle with the shank of a drill bit 1/64" less in diameter than its height, and tune the bass string to concert pitch, and check at each fret for buzzes. Don't worry about getting the saddle placement right during this. Keep reducing the diameter of your temporary saddle until you find some buzzes happening. Make sure the buzz isn't coming from just one fret that may be still a bit high. If you're getting buzzes from more than one fret, you now know that the saddle has to be at least 1/64" higher than that drill bit.

I like to shave floating saddles to height by putting a small plane upside down in a vice and using it as a one-blade jointer planer. You can get real fine shavings off and easily keep the bottom of the saddle straight. (By the way, make sure the area where the saddle is going to sit is flat before you start any of this work! A rocking saddle will rob the dulcimer of sound.)

updated by @dwain-wilder: 01/31/23 02:30:24AM

Dwain

I think you are spot on with your guess. I need to get the bridge adjusted a little lower but changing that to the back side puts it very close to Equal temperment.   I could not see the obvious, I was getting pretty frustrated!  Thank you

Bill R

This is a weird fretting scheme. The octave (at which an instrument would have been intoned) corresponds to a scale length of 28.12". That just does not make sense in a kit.

My best guess is that the nut is misplaced. To find out if that is true, tune the dulcimer's strings so they are all correctly tuned when fretted at the octave (7th diatonic fret). Then see how well they are tuned at the second octave. Then check whether the octave harmonic tones match the fretted tones (if you're not familiar with plucking harmonic tones on a string see Guitar Harmonics w/Fretted Notes - Lick Of The Week - Guitar Lesson - YouTube). If those are not in tune with the fretted tones, move the saddle until they are.

Then check whether the fretted tone is right at each fret all the way up the fretboard. If they are all in tune then only the open string is off —meaning the nut is not in the right place. Get the nut placed so it too is in tune.

My guess is that the nut is .12" too far back. And the whole fretting job may be problematic. If you don't want to re-cut all the frets, you could simply put a piece of wire about the same diameter as the fret height and tape it in place once you've found where it sounds best with the surrounding frets and any chords of interest. Then mark where that wire touches the fretboard and make your cut there for the 6-1/2 fret.

I recently acquired what I believe is an all walnut  Davis kit dulcimer. 5 strings, peg tuners, 14 -1/16 inch from nut to 7th fret. floating bridge, no tag, name date etc. It was put together very well, good joints and finish .   I wish to add a 6 1/2 fret. My problem can be shown with the comparison chart I have attached showing calculated locations for JI, EqI , measured with a tape then with a 24" digital caliper. I have run the calculations from 27 to 28 1/2 " and nothing matches, but when tuned to DAd, it is good on the electronic strobe  tuner and sounds ok with my other dulcimers. I can locate the 6 1/2 fret by ear but am wondering how these frets can be vary so much yet still be in tune with equal method calculations. Any thoughts or comments?