New, efficient desktop 3-D design software eliminates these problems by creating an unambiguous solid model of a mold assembly. Working with topologically complete and accurate models, engineers and designers can ensure that parts fit properly and function as intended before tools are made.

3-D models enable designers to better visualize where to put cooling lines to maximize heat removal and minimize cycle times.

Using 3-D solid models, moldmakers also can take advantage of rapid prototypes made by additive fabrication techniques to verify that part models are correct before designing molds. These 3-D mockups also are valuable aids to mold designers, helping them to see how to position parts in the mold and where cams or sliders must be used to mold parts with undercuts. Using processes like selective laser sintering, mold designers can fabricate mold inserts with conformal cooling channels to further optimize cycle times. Designers also can use 3-D digital mockups to verify that designs not only fit together but that they work properly.

Working in 3-D doesn’t require ignoring drawings altogether. Moldmakers and designers can produce drawings more quickly from 3-D models than by manual or 2-D computer-aided drafting techniques. Errors in projecting views that are common in 2-D drafting simply can’t occur when computers project unambiguous drawing views from 3-D product models.

Moreover, designers can change drawings more quickly with 3-D CAD because a single change in the 3-D master model updates all drawing views with perfect accuracy.
Another benefit of 3-D CAD is the increasing interoperability with complementary software, including analysis programs. For example, 3-D CAD interoperates with mold filling and cooling analysis programs to ensure that parts don’t warp or show shrink marks, and that companies can meet production cycle times. Kinematic analyses can ensure that mechanisms such as cams and sliders don’t interfere with other parts of the tool.

When it’s time to make the tool, 3-D computer models, not drawings, are the geometry master. The toolmaking plant puts these masters to many uses. Numerically controlled mills can cut core and cavity surfaces from the models. Tool surfaces and first articles can be inspected using optical scanners or coordinate-measuring machines and compared to the 3-D CAD master. The master can generate bills of material for cost estimating, purchasing and manufacturing resource planning.