"Wood Density" Selection Page...
Modified Last:5/2021
Page WS_05/15
By David Langsather, webmaster: www.violinresearch.com
..I am going to suggest we pay attention to the density of the spruce and maple wood we pair up in making our instrument, as a means to contribute to our future violins level of success. I know that one can compensate if the spruce wood is relatively dense and the back plate wood is relatively less than normal dense; but doing so makes problems we could do without!
..Given that the weight and volume measurements are all metric; we can directly translate these into relative density {because there are 1,000 KG weight in one cubic meter.} {Relative to liquid water...}
..Thus all the figures above become density designations. Using this information :
Maple Violin Wood ...................................................Density ..Ratio :........Spruce Violin Wood ...........
Low Density.......0.54 to 0.58 density (0.58 average)....0.63........................[0.34 to 0.39 density ](0.365)
.
Average Density..0.63 to 0.71 (0.67 Average)...............0.64 .....................0.40 to 0.46 density (0.43)
...
High Density.. 0.72 to 0.78 (0.75 Average) ....................0.65 .....................0.47 to 0.50 density (0.485)
.In simple terms; if the spruce for the top plate has a relatively higher density, then the back plate Maple wood should have a relatively higher density. Spruce can be between 0.34 density and 0.50 as long as its match to the Maple wood is the correct density ratio. Maple between 0.54 and .78 density can be used at times.
..Notice that the density ration goes up slightly for increased density levels...
>>Example One: Our Spruce top plate wood has a specific gravity (density) of 0.45; At that density, the density ratio is 0.64; so the back plate wood should ideally be (0.45 divided by 0.64 ) = 0.70 relative density.
>>Example Two: Our Spruce top plate wood has a specific gravity (density) of 0.34; At that density, the density ratio is 0.63; so the back plate wood should be (0.34 divided by 0.63 ) = 0.54
>>Example Three: Our Maple back plate wood has a specific gravity (density) of 0.73; At that density, the density ratio is 0.65; so the top plate Spruce wood should be (0.73 multiplied by 0.65 ) = 0.47
>>Example Four: Our Maple back plate wood has a specific gravity (density) of 0.67; At that density, the density ratio is 0.64; so the top plate Spruce wood should be (0.67 multiplied by 0.64 ) = 0.43
..Now I realize that we probably will not have the specific wood on hand, but we should get as close to a density ratio match as possible.
..If nothing else, we will know that our proposed wood is unacceptable when way outside the density matching ratio, so we can keep looking for acceptable wood.
..While we are at it; let us get enough of the spruce to supply ALL the Spruce wood in the violin; and enough of the Maple to supply ALL the maple wood in the instrument...
