Granted Patent
Utility
US 6,554,056 · App. 10/025,246
Method of modifying patterned sand molding elements through machining for producing prototype metal castings
Inventor:
Ronald Gustafson
Patented Case
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Granted: Apr 29, 2003
Filed: Dec 18, 2001
Inventor
Ronald Gustafson
This patent predates the USPTO's electronic file wrapper — prosecution documents from this era exist only in the Patent Office's paper records. A certified copy of the file history can be ordered from the USPTO's paper archives.