Filling fingernail gouges in sides of keys

[Jon Page]

On giving this more thought, I would pass on the filling endeavor.
The cart is before the horse... It's like deciding to gild the plate
after you restrung the piano.

But afterthoughts are sometimes the Grandmothers of Invention.

Here's what I would do so as not to have a dissimilar material on the key:

Route out a strip with a 1/4" or so bit with a plunge router. Start 
at the front
and route a slot right off the back of the head. Inlay a piece of 
wood fashioned
from suitable stock. Trim rear edge to the angle of the key.

The diameter of the router bit would be determined by the width of the damage.
The only filling that may be needed would be at the top front edge of the inlay
if you left it rounded. Otherwise squaring the corners would preclude rounding
the ends on the inlays.
-- 

Regards,

Jon Page