Finishing wood enhances the beauty of the wood while protecting it from moisture, dirt and other contaminates. The finish chosen for a plucked stringed instrument must also be considered for it’s tonal properties.
Before a finish is applied the dulcimer receives final scraping and sanding.
A note here about preparing a surface for finish; modern industrial standards have created an expectation where even hand made items are often expected to look as if they were made by machine and inspected with microscopes.
The hallmarks of hand-craftsmanship such as the occasional tool mark or irregularity are often perceived as flaws.
Wood, the beautiful organic material of choice for stringed instruments, is often expected to be flat and shiny like a Formica counter top!
This presents woodworkers and luthiers who work by hand with a dilemma; is the goal of the crafts-person to hand-make something that looks like it was made by a machine? Compare this to a calligrapher attempting to write a manuscript by hand that would look like it was printed by a computer!
There is another extreme; some people believe the term “hand-crafted” implies rough or crude work made without care for detail. This is another matter and should not be confused with the organic, natural flaws of materials and work produced by a caring, experienced crafts-person.
I prefer wood to look like wood. I appreciate the grain of wood enough to avoid burying it under acres of plastic or making it look like it is under glass!
I experiment with different finishes but primarily use shellac and a variety of oil-based varnishes, often in combination.
I am also moving away, quickly, from using any toxic finishing materials and solvents.
Shellac is traditional, non-toxic and relatively easy to apply. By building several (or many) thin coats very little material is added to the wood. This produces a transparent, hard and protective finish that does not dampen the tone of the dulcimer. A shellac finish is easy to repair as each new coat of shellac dissolves into the previous coat.
Shellac looks beautiful on both hardwoods and softwoods. Shellac also comes in a variety of shades that can be used to accentuate the color of the wood.
Shellac has two potential drawbacks: it scratches more easily than some finishes and it is alcohol soluble. If a dulcimer finished with shellac gets badly scratched or someone leaves a glass of bourbon on their dulcimer it can easily be repaired.
Oil varnish is another traditional finish with a long history of use on musical instruments. Oil varnish should not be confused with raw oils like linseed or tung oil. Raw oils will soak into the wood and often do not fully dry. This can be advantageous on furniture but can deaden the tone of a musical instrument.
Oil varnish is made with linseed or other oils (surprise!) that have been processed and/or mixed with resins and additives to speed drying time, degrees of hardness, color, etc.
Oil varnish adds a deep, lustrous and protective finish. If properly applied it will have little effect on the tone of a dulcimer.
Oil varnish look great on hardwoods but can cause the harder and softer grain of spruce and cedar to “washboard.” I personally think this is a beautiful effect as the wood looks and feels very natural. This light washboard effect also occurs over time to many fine finishes as they continue to cure even if they were originally as flat as glass. If I prefer a glass smooth surface I will seal the soundboard with shellac prior to varnishing. Give it a few years and it will develop a beautiful texture anyway.
Depending on the wood and the desired effect I sometimes seal and undercoat a dulcimer, or parts of a dulcimer, with shellac. On some of my personal dulcimers, or if requested, I will use only shellac on a soundboard.
I prefer applying finish by hand. I use various padding techniques and occasionally brushes depending on what I am working with.
In most commercial operations finish is sprayed.
If you are going to spray finish, especially lacquers and other toxic substances, please avoid following the example of this finisher of the not-so-distant pass who is completely disregarding his health and safety while spraying:
The toxic hazard of such work has led many a person down the road of deviant, unexplainable and erratic behavior!
Instead please follow the fine example set by the man below who chooses to use modern state-of-the-art safety equipment:
A lesson for us all!