This page contains a Flash digital edition of a book.
A SHINING EXAMPLE The “Viseum” in Wetzlar, Germany, is featuring


a 7.5-ft. cast bronze, nickel-plated spoon sculpture produced using the selective laser sintering (SLS) method. Watch a video demonstrating the 3-D


printer’s RP process at http://www.voxeljet.de/en/systems/vx1000/#. SLS prototypes can be used for sand and investment


casting. 


It took approximately 10 hours for the machine to bind thousands of 0.00591-inch (0.15 mm) powder layers together.


The CAD data of this nickel-plated bronze sculpture was transferred to a printer, which produced a plastic model of the bowl of the spoon.


The printed polymethyl methacrylate (PMMA) model was used to produce a sand mold that was cast in bronze.


greater design fl exibility, as the elimina- tion of the tooling step removes some limitations from the process of achieving the desired geometry. One of the newest rapid manu-


facturing approaches is for molds and cores to be computer numerical control (CNC) machined from a block of bonded sand. It skips the patternmak- ing step for prototyping and short production runs, and allows designers to test a casting before creating the permanent tooling. T is method off ers a particular benefi t for larger parts that cannot be produced in one piece using additive RP equipment. In addition,


robotically automated production lines can produce machined molds quickly.


A Diecasting Difference For diecasting, the options for rapid


manufacturing are machined tooling, laser-based die insert fabrication and plaster molding. T e rapid manufacturing method


most often employed for diecasting production is plaster molding. Depending on the required surface fi nish and accuracy of a diecast part, an RP-generated pattern can be used to create a rubber mold, which is then fi lled with plaster to form a mold the metal is


28 | METAL CASTING DESIGN & PURCHASING | Nov/Dec 2012


poured into to produce a casting. Plaster castings often are used to eliminate hard tooling costs for parts with tolerances suited to this method, as well as for prototyping or testing. T ey also are employed as a temporary substi- tute while the hard tooling is prepared.


@


ONLINE RESOURCE


“Rapid Tooling Opens New Diecasting Doors,” at www.metalcastingdesign.com.


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60