Violin Rib Tuning....
David Langsather, Violin Maker
3425 Fairhaven Avenue N.E.
Salem, Oregon 97301
firstname.lastname@example.org for e-mail
...Just a few words might be useful here.
..The goal Tap Tone RIB frequency is 242 HZ horizontally, all over the exterior rib surfaces, and even from top to bottom at each point.
..This tap is applied to the ribs horizontally from the side (either inside or outside and 90 degrees to the surface. Compare to the wood reference tap tone scale tool. Adjust the areas that are above 242 HZ by sanding or scraping the surface, or insides of the rib stock, in the region that is too high until it becomes the 242 Hz goal frequency. Leave the too low areas alone. Material can be removed from either inside or outside of the ribs to the same effect. A (1) mm thick rib (0.0394") should be close to the goal frequency automatically.
..To deal with areas that are too low in horizontal Tap Tone; remove a small amount of material from the inner, inside edges of the glue liner strips on their inside direction edge as needed, on either top or bottom glue liner strips in order to raise the Tap Tone up to the desired 242 HZ.
(Be sure to leave the glue surface its full width for glue joint strength.)
..Cross Section drawing of the violin ribs and glue liner strips...
..Scrape or sand from either side to evenly bring down too high side tap tone down to 242 HZ ..OR.. lightly sand the inside surface evenly of glue liner strips.
..To RAISE side tap tone to 242 HZ, remove material in a bevel shape from glue liner strip that is lowest until rib side tap is evenly 242 HZ, top to bottom.
..To LOWER rib side tap.. lightly sand here.