Simple regulator on 2nd octave strings
One of the problems associated with old harps is that the neck moves toward the soundboard with age. This means that the strings are slightly shorter, and at the high end of the instrument - first second and third octaves, this causes the interval between flat and natural to widen. With Erard harps there is a movable wrest pin to adjust for this effect, but on the Dodd there is a fixed pin. The solution I came up with is very simple but works well. Essentially you make a brass tube that will fit over the pin - drill to the smallest diameter and then ream out with a taper reamer so that it fits onto the flared pin better. You then cut back the top side of the sleeve leaving a small area of metal that bears onto the string. The effect of this is to slightly shorten the string so the fork now produces the correct interval. By profiling the metal lug that bears on the string, you can adjust the interval. Fit a brass grub screw (2mm or so) to secure it. Don't use steel screws unless you don't mind the brass pin being damaged.
Hopefully the illustration shows it - if you want more details then email me.
The other trick is to make a new fork with the pins offset so that the vibrating length of the string is a little longer - this is feasible for 3rd octave and below. Above that the forks are too small to gain useful length.
Offset pins on 3rd octave G fork
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Last update to this page: September 10th 1999