'End of Fingerboard' neck tuniing.

...This will be one of the last tuning steps to complete an acoustically tuned violin. Complete the scroll and peg box areas with tuning pegs installed. Complete the shaping of the underside of the neck and fingerboard tuning. Then : ....
...When we tap the neck wood sideways just under the intersection of the fingerboard and nut, we want this tap tone to be 306 HZ from both sides.
Also in harmony with the tap under the heel of the pegbox at 252HZ.

...This will REALLY help with the beauty and brilliance of the tones played.

..This is the side tap frequency we want to adjust to (306) HZ from both sides.
..If too high, then carefully sand/ scrape small amount of wood from each side until it is 306 HZ on both sides.
..Underneath the tap tone of the end of the peg box needs to have an in harmony 252 HZ tap tone.
..If the side tap is too low, then you will find that the bottom of the peg box heel is higher than 252HZ. Just sand or file this back to 252HZ and you will find that the side Tap is now at desired 306 HZ.

..ONLY as an optional method.....This back surface of the peg box can also be adjusted to control the side tap we are interested in adjusting.
..If the side tap shown above it too high (above (306 HZ), then an even layer of wood will need to be glued on to make this end surface thicker.
..If too low (below306 HZ), then wood is removed evenly from top to bottom on the side that is too low. If both sides are evenly low, then remove wood evenly from the back of peg box until the side tap is adjusted.
..I normally use a sharp flat blade chisel to carve away the excess wood.
..Only small amounts make a change.
..Tap along this surface from bottom to top in area of adjustment and remove first any areas with higher tap tone than others.