My latest build, #4

[Guitarpeggio]

Here is my latest build, made for my brother who has a cabin in the Carolinas by a river. The fingerboard is padauk and reminds one of the red orange clay soil found there. I tried some different things this time— an hourdrop shape to mimic the irregularity of a winding river, creek stones and birds for sound holes, and a blue wash for the stain to attempt a watery look. This forum has given me great encouragement! Thank you!

Edited November 13, 2022 by Guitarpeggio
Typo

[NoterMan]

Nice job!  The wash is just right -- glad you didn't overdo it or use a brighter blue.

 

[KWL]

I agree with NoterMan. You built a very nice dulcimer.

Ken

"The dulcimer sings a sweet song."

[Guitarpeggio]

Thank you both! It took me awhile to experiment with just the right amount of stain without obscuring the grain. Also, I would love tips on my next build as to how to make the fingerboard perfectly flat before fretting. In my inexperience I discovered some frets fretting out and a very slight rise in the middle of the fingerboard after assembled. I fixed it now, but if I could save me some trouble next time that would be great!

[NoterMan]

Well, a planer is the perfect (but expensive) solution.  

First, arrange to cut your fretboard so that the grain is at right angles to the future top, not flat-sawn with gran lines that parallel the top.  

Barring a planer or hand planes and skill using them, you can make a flat sander.  I made mine from an inexpensive  3/4" x 6" x 36" replacement marble window sill from one of the Big Box stores.  To that I glued two (different grits)) cut-open 3x24 belt sander belts (grit side up, of course).

 

[KWL]

I don't necessarily make a flat fret board. I will usually hand sand from the third fret to about 14th fret taking it down one or two thousands of an inch. I know it sounds ridiculous to do this, but it avoids recrossing some high frets later on. Another way to avoid the rise in the center is to make wider slots for the fret and glue them in place. The pressure of the fret tang against the wood tends to push the wood up in center. A slight concave fret board can avoid this.

Ken

"The dulcimer sings a sweet song."

[Guitarpeggio]

thank you both for the suggestions! Noterman, I am limited in my tools, but I love your window sill idea! And Ken, I like your idea of the slight concave board. While your idea takes a bit more time, I don't mind at all, especially for saving me redoing frets later!  Thanks both of you for different but very helpful ideas!

[NoterMan]

Ken's right.   A lot of old dulcimers had concave fretboards lowest around the 7th fret.  Idea was that strings vibrate in an arc like a jump-rope and the spot half way between the two ends is the lowest part of the arc...

[davis]

Would you where I can find some free plans Thanks

[KWL]

Here is an article which includes a plan the can download for free: https://www.woodworkersjournal.com/wp-content/uploads/WJC001-Mountain-Dulcimer.pdf

Ken

"The dulcimer sings a sweet song.'

[Dwain Wilder]

I agree with Noterman. The fretboard should be the best piece of straight-grain, clear quartersawn stick in the whole instrument. And as he says, orient it with the grain lines running vertically. Why: because wood swells by expanding the spacing of the grain lines. So any temperature or moisture variation will affect only the fretboard's width, not its playing surface.

As for properly surfacing the fingerboard, you will get the lowest action if it is designed with a good theater's audience floor in mind: Each seat should be just a bit lower than the one behind, so you can see over the head of the person in front of you, with a clear view of the stage. But about 2/3 of the way down, that need is overtaken by the ability to see the stage without undue strain on your neck to look up, so the floor begins to rise again, but is still a bit below the stage at front-most seat.

Getting this right requires a good set of feeler gauges, ranging from .0015" to .025"

On the dulcimer fretboard, that amounts to a very shallow parabola, more or less, with its center line slightly tilted toward the stage. If your fretboard measures at the 5th fret about .010" clear of a true straight-edge laid between the place the nut will go and the end of the fret hollow, you'll have one measurement about right. Another shorter straight edge laid from the place of the 1st fret to the last fret should be about .070" above the fingerboard at about fret 8. And that longer straight-edge laid between the 1st fret and the stage the saddle will sit on should be no more than about .010" above the fretboard at the last fret.

But that is one third of the story. The other third is holding that longest straightedge up on the fingerboard and looking at a strong light coming through. That should be a gradual, very shallow crescent of light. Likewise with the shorter straight-edge.

The third third of the story is use the feeler gauges to find lumps in the curve. To do that, lay the straightedges on the fretboard as described above, and find the thickest gauge you can slide underneath. That's how you find the maximum distance at fret 5. But then hold it loosely and feel how far it will travel up and down the fingerboard under the straightedge. Then try the next smaller gauge in the set, and see how much further it will slide, noting how much further. And so likewise with each gauge in the feeler gauge set, especially noting where the gauge will feel a little tight but then loosen up if you push it a bit further away from your starting point: that is your signal that there is a small lump there. Mark that location with chalk, and sand the area until the chalk goes away, gradually increasing the length of the stroke as you go (so you don't make another lump!).

All three of those methods, used together, will get you a fretboard that will allow low action, easy playing. And the offset of the saddle to account for the sharping caused by pushing the string against the fret will be minimized also, so your dulcimers will play in tune with a wider variety of string sets and tunings than most dulcimers.

The exact measurements are what I use in my own work, with VSL varying from 27-5/8" to 24". Your own optimum may be different, depending on your design and vsl.

Hope that helps. Oh and by the way, try building with tops and backs that are quartersawn also. They are the second and third of five primary elements making major contributions to the voice quality and acoustic dynamics in the dulcimers you build. A straight-grained top soundboard will be material you will be able to be predict the behavior of, if you keep using the same species for awhile, keeping a log of the the tap tone tests you make of the board before rough-cutting it to the shape of the body.

Edited January 22 by Dwain Wilder

[Guitarpeggio]

Thanks for the extensive suggestions, Dwain! I still consider myself a relative beginner in all of this, though at the moment I am working on dulcimer #5. Because of life and other projects I haven’t checked this forum in awhile, but just noticed your post today. I am nowhere near that level of detail in installing frets. But your suggestions clearly give me ideas on how to improve, and avoid fret issues later.

One thing I am curious about, however, is leveling humps. If you are sanding the area in between the metal frets, that doesn’t seem to address the issue of a high metal fret to me. Am I missing something?

Again, thank you!

Edited March 31 by Guitarpeggio