VS3D Sculpting/Machining Example - A Proposed Design For The Nevada State Quarter.
This piece started out as a hand drawing of the Virginia & Truckee locomotive #18:
The drawing was scanned as a ".tif" image and imported (image brightness mapped to height) into VS3D. The VS3D hammering and region tools were used to interactively sculpt it in relief. Similarly, an image of a 19th century Carson City $10 gold coin was imported (again with image brightness mapped to height). The lettering on the coin was changed to suit the overall Nevada quarter design. USGS DEM (Digital Elevation Model) data was imported into VS3D and used directly for the Nevada relief map. After all the elements were brought together and finalized, VS3D generated a rendering of the sculpture:
The virtual sculpted surface was then machined in a 4 inch diameter circle on a 6x6 inch piece of yellow brass. The computer-controlled milling/engraving machine is a model 844 made by S&W Engineering:
The machining passes from rough cut to final finish included:
1. A spiral pass using a 1/8" diameter ball-end mill.
2. A horizontal traversal pass using a 1/8" diameter ball-end mill.
3. A vertical traversal pass using a 1/8" diameter ball-end mill.
4. A horizontal traversal pass using a 1/16" diameter ball-end mill.
5. A vertical traversal pass using a 1/16" diameter ball-end mill.
6. A horizontal traversal pass using a 1/32" diameter ball-end mill.
7. A vertical traversal pass using a 1/32" diameter ball-end mill.
8. A spiral pass using a 1/64" diameter ball-end mill.
The maximum depth of relief of the final machined piece is approximately a tenth of an inch. Total machining time was approximately 14 hours (10 of that was for the final "lights out" spiral pass). Much higher resolution is possible with more machining time and smaller tool bits.
The overall size of the piece can be gauged in comparison to a Sacagawea dollar coin:
A close-up image shows the machined details. The pastel iridescent colors (similar to a Compact Disk) are the result of extremely small machined swirl marks:
A complete description of the design is as follows:
Nevada’s unique Great Basin topography symbolizes the state’s geologic importance. The famous Virginia & Truckee locomotive #18 (the "Dayton") served Nevada during the great gold & silver mining boom, and is reminiscent of the Silver State’s "Wild, Wild West". The Dayton is on permanent display at the Nevada state railroad museum in Carson City. The coin image is patterned after coins once minted from Nevada gold and silver at the Carson City mint. It shows the state capitol’s famous "CC" mint mark. The legends were changed to show the official Nevada state mottoes "All For Our Country" and "Battle Born". The pair of aces is representative of the state’s gaming industry. The ace of diamonds symbolizes the glamour of Las Vegas, and the ace of hearts symbolizes the romance of Nevada. The small square on the map shows the location of the mysterious and legendary "Area 51".
Proposed Nevada state quarter design by Daniel Carr, with assistance from Eva & Dave Bauer.