Glue Liner Strip Adjustment (tuning)...
...The glue liner strip is the spruce (or willow) wood that is glued to the top and bottom of the ribs inside the instrument to provide a wide enough glue surface to form a secure joint when the top and bottom plates are glued to the rib structure to form the completed violin body.
...Gluing the liner strips to the 1mm (.040") thick rib stock raises the tap tone of the ribs. When the liner strips are first bent and glued in place and then the rib heights are shaped to their final size; tapping sideways against the rib surface will produce a tap tone that is usually higher than our goal tap tone frequency of 198HZ. {G note on piano, below middle C}.
...I would suggest that the rib tap tone (tap from the side) should be set at 198 HZ (vibrations per second) evenly all over the rib surface, in all areas of the rib structure.
...This way, the vibrating violin plates are not fighting the rib structrue when a vibration reaches the side of the plate but instead are in sync with the back plate's vibration which may well help overall tone and power.
...The basic tap tone adjustment concept is that as the bottom ( inner) edge (the edge of the liner strip that is toward the inside of the instrument) is beveled, the tap tone of the glue line surface is lowered.
... Should the liner strip be too low already, the tap tone can be increased by removing material from the side of the glue liner strip. If you must do this, then leave the very top surface its full width as this is important for a secure glue joint.
bevel this surface (away from the glue surface) to lower tap toneof the upper area of the rib.
remove material here to raise top tap tone.
Side cross-section view of the rib section of the violin family, showing rib and liner glue strips.
1 mm thick violin ribs
(revised 8/2017)
Page AA_15
.... I want to mention that my current practice is to cut the glue liner strips into each corner of each end block and all the corner blocks, with a 45 degree tight angle joint. The idea being: to transmit the sound that the liner strips pick up to the same area of the opposite plate through the blocks.
Since the last three violins seem to exhibit superior sound properties, you might also want to try this method instead of just fitting the glue liner strips tight against the side of most of the blocks, as is usual practice.
..These side tap tones should be consistently 198HZ on all areas of the rib structure. (Same as the center tap to the back plate).
