Rapid Prototyper Puts a Spin on Faster Mold and Cast Parts

      3-Dimensional Services has added the Tekcaster TEK-100D spin casting system from Tekcast. The new system, with capacity to cast or mold parts of up to 9" x 6" x 3-1/2", allows fast and cost effective (because there is no need to build any hard tooling such as dies and molds) casting of zinc, tin and lead-based soft alloy components, for applications requiring higher strength metals, plus the injection molding-like of thermoset plastics. The spin casting process, combined with the company's other, existing rapid prototype technologies and especially its three types of rapid modeling, results in prototype parts being finished up to 70-80% faster than traditional prototype methods permit.

      The spin casting process begins with a model, and at 3-Dimensional Services, these models can be made via stereolithography apparatus (makes a plastic part), laminated object manufacture (a wood-like paper part), or by selective laser sintering (a hardened powder plastic or metal part). Whichever method is used, CAD data files are downloaded to the appropriate model system and the completed replica of the part is finished within hours. At this point, the "tooling" for the spin casting process begins-depending upon the application, either organic rubber or silicone rubber compounds are poured over and around the model, with alignment pins placed, as are cores and pull-outs added as needed. The rubber mold is then cured in a heated vulcanizing press, making a durable, resilient and accurate tool. Importantly, again depending upon the application and the size of the part to be cast or molded, multiple pieces can be included in a single rubberized mold.

      Once cured, the mold may be manually gated and vented for air escape, and the runner system (the distribution channels for the liquid metal or plastic to flow) is created. The mold is then placed in the Tekcaster unit, which is adjustably set for rpm, cycle time, and clamping pressure. As the cycle starts, the liquid material is poured down the Tekcaster's port and into the spinning mold where centrifugal force pushes the liquid through the mold's runner system spreading evenly to all cavities of all parts. When the cycle is over, the liquid material is given time to solidify and set up, then the pliable rubber mold allows quick release of the parts. Typical production times provide up to 50 to 60 cycles per hour when using metal materials, and 10 to 15 cycles per hour when longer-setting plastics are used. Besides the ability to run multiple parts in a single cycle, the rubber molds stand up to repeated castings or moldings, so quantity prototypes may be made.

      Because of the dimensional precision and surface quality afforded by the spin casting process, completed cast or molded parts are readily suitable for assembly or machining tryouts, or can be processed through painting, coating or plating steps without secondary clean up.

      In addition to the spin casting process, 3-Dimensional Services offers a comprehensive list of rapid prototype build capabilities, including hydroforming, high definition stamping, traditional injection molding and casting, fabrications, EDM, high speed machining, laser cutting and welding, and complete assembly operations along with extensive design service and engineering analysis.

      For more information contact:
      3-Dimensional Services
      2547 Product Drive
      Rochester Hills, MI 48309
      248-852-1333
      Fax 248-852-2110
      www.3-dimensional.com