I have found that the best material to use for making soundboard shims comes from the front and back boards of old pipe organ pipes. These boards are usually, truly quarter-sawn, and much thicker than the sound board. The side pieces of the the pipes are not suitable. If you will buy a thin-kerf blade, you will get almost as much shim out of a board as you will sawdust. Also, the lengths are quite long and shimming long cracks can be done with one piece. Find an organ repair business, and see if perhaps some old, unusable pipes are available. the spruce is harder than most of the new stuff, and the color is often much closer to the color of an old soundboard. Ed Foote Precision Piano Works Nashville, Tn.
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