The three key frame rails are made from maple; the front rail is shaped with
a small concave curvature thus the fit between the two is perfect. The crossbars
are made from spruce so that the complete key frame is elastic and will fit perfectly
to the keybed without gaps that may produce noises. The keys are reinforced at
the top by the "key button" which is made of maple
and the capstan and back checks are inserted in a beech block which is glued to
the keys.
The touch weights are fixed from 48 grams at the treble to 52 grams at the bass.
The up-weight, which is extremely important, is also controlled; in particular
the up-weight is generally 21-23 grams in the bass and 25-26 in the treble.
