Casting The Iron Plate (Frame) ...

Traditionally, the iron frames (plates) have been cast by a process that uses wet sand.
An impression made in the wet sand by a pattern leaves a cavity which is filled with molten
iron to form the plate.
Certain problems inherent with this method are:
1. The exactness of measurements and contours of the cavity
are compromised by the crudeness of the grainy, wet sand that attempts to duplicate
the pattern.
2. Uneven cooling caused by the extreme temperature differences between the molten
metal and the wet sand create structural weakness.
3. Any decoration cast by this method looks crude and imperfect.


Yamaha Vacuum Shield Mold Process (V-Pro)

Yamaha eliminated these problems by developing the Vacuum Shield Mold Process (V-Pro).
1. A mold is created by utilizing the vacuum principle to hold fine grain dry sand firmly in place
which exactly duplicates the pattern.
2. Molten metal is then poured into the mold, and because the sand is not wet, the metal
cools evenly rather than unevenly from the outside in as in the case with wet sand.
This improved cooling minimizes the problems of internal stress.
3. Decoration and surface smoothness are greatly improved.


Remember, in Colorado, Natural Piano Center is the place to be!