New tool-making approach for 'weldless' parts.

A new tool-making method is integral to a molding technique that's said to produce parts without weld lines. The new 3D Weldless Manufacturing System injects a material at its glass-transition temperature into a relatively hot mold (around 300 F). After filling and packing, the mold is quickly cooled to about 140 F. The result is said to be a stress-free part with high surface finish and a cycle time 50% to 67% shorter than usual.

One key to the process is a new 3D CNC milling machine from Makino that rotates the metal block (photo below), which allows machining of all mold contours and conformal cooling channels simultaneously. The resulting mold can have undercuts and stand-alone features integrated with optimized cooling and venting in a single piece of steel, while a conventional mold would require inserts.

The technology was created by a consortium in Japan and was displayed for the first time at the Platex Osaka show this spring. The consortium includes Makino, GE Plastics Japan (for materials), Hitachi Metal (tool steel), Mitsuhishi (injection press), Fuji Seiko (mold making), and Sysko (mold-temperature control). The consortium will develop a website in the near future, but GE is a principal contact. Tel: [phone] * PT Direct : 32YT

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