This article is from the Classical Guitar FAQ, by Joshua Weage (jpweage@mtu.edu) with numerous contributions by others.
Nail Maintenance
----------------
The length, shape and surface of your fingernails have a direct effect
on your playing: how you care for your nails will affect your music as
much as how you practice. A short, well-shaped, smooth-edged nail
will facilitate fingerstroke and produce a clear tone; a neglected
nail will interfere with right hand efficiency and will sound raspy.
Differences between individual nails will disrupt right hand technique
even further, particularly in alternation and arpeggios. For the
developing student, this can cause a great deal of wasted practice and
frustration. Finally, regular and proper care of your nails is the
single, foremost way to prevent them from breaking and requiring
repair.
Although everyone has differences in the curvature, thickness,
resiliency, texture and other qualities of their nails, observing the
following can significantly improve your playing. You'll need a
diamond file and 500 grade sandpaper (preferably open coat, not
waterproof; a multigrade cosmetic nail buffer can also substitute for
sandpaper):
filing: Hold the file pointing toward your face (looking down its
length), with the finer surface facing upward. Holding your
finger at a ninety degree angle (perpendicular) to the file,
place the nail on the surface. The vector of your finger
should be around forty-five degrees to the plane of the
file, so that the nail is being filed somewhat from beneath.
File the nail by evenly drawing the file back and forth with
the left hand, exerting even pressure and guiding it in
place with the right thumb.
length: Hold your hand with the palm facing you, fingers extended
with the tips pointing upward. You should see the tips of
the nails just peeking past the fingertips (1 to 2 mm past
the fingertip is plenty). Excessive length causes the nail
to drag along the string, causing wasted effort and
disrupting the timing of alternation and arpeggios. Uneven
lengths are also disruptive; make sure no nail is
significantly longer or shorter than the others.
Note that excessive length is common among players with
little or no training; the extra length requires less
precise nail placement during fingerstroke and can thus make
playing seem easier. If you are significantly shortening
your nails, you may initially find your fingerstroke is less
accurate. If so, spend some time concentrating on placing
on the exact same spot of the nail for every fingerstroke.
shape: Hold your fingers pointing toward you, so you see only the
edge of each nail; each edge will form a more straight or a
more curved line. Now look at the entire nail, from above.
If filed perpendicularly and from beneath, the straight-
edged nails should have a more square shape, and the curve-
edged nails should have a more elliptical shape. If the
edge of the nail is straight but the shape is not very
distinctly square, you've probably been filing the nail from
its side and the nail will have to grow out a bit to develop
more body on the corner. If the corners of the square
shapes are sharply pointed, use the file to round them (but
don't alter the basic shape).
surface: After the nail is filed, its edge must be finely polished.
Take a small portion of 500 grade open coat sandpaper and
rub, with a back and forth motion, the same spot of
sandpaper on the edge of the nail, particularly
concentrating on the left side of the nail. The surface of
the sandpaper will wear down as you rub, creating an
increasingly smoother polishing surface. Keep rubbing until
the edge is as smooth as a glass surface.
After you're finished, visually inspect each nail for consistency in
length and shape. Use the thumbnail edge to feel each fingernail edge
for flaws in smoothness and shape. If your nails are properly shaped
with the edges finely polished, there should be a distinct increase in
ease of execution, and also in tone quality.
---
Stuart LeBlanc
gustav@mintir.new-orleans.la.us
 
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