A Three-Dimensional View of Molding Issues

Identifying design-for-manufacturing issues from a molded part's CAD file can be tricky, especially for engineers without much molding experience. But a new online tool from Protomold makes it downright easy to see moldability trouble spots right on a computer screen.

The company recently enhanced its on-line quote generation system, adding a dynamic 3D view of moldability information. These new visualization capabilities are part of ProtoQuote, a Web-based system that generates interactive price quotations for Protomold's rapid injection molding service. Users simply upload CAD files of their plastic parts and the ProtoQuote report comes back within one business day.

If you like the quoted prices, Protomold will go ahead and produce your injection molded parts in as little as three business days. The quotation system drives an automated mold design process, and the company makes tools very quickly using high-speed machining centers and aluminum mold materials.

ProtoQuote, however, contains more than just pricing information. The system has always included a detailed 2D design-for-moldability review, which graphically highlights problems such as inadequate wall thickness or draft angles. The system also highlights part design features that require molds too complex for Protomold's current manufacturing capabilities. For example, Protomold mills its molds, so sharp corners and other features that require EDM are out. And the company only supports a limited number of tooling actions, so undercuts and out-of-draw holes can be a problem. (See The Key to Speed for more information. The sidebar at the bottom of the page contains technical details on the Protomold process).

One hidden value of Protomold's design limitations is that they tend to correspond to lower cost tooling and molded parts. Sometimes you truly do need a complex tool. Yet, if it is possible to make your part within a relatively simple milled tool, it's probably a good idea - even if you have to modify your part design slightly to make that happen.

And this is where the new 3D feature comes in. It allows users to dynamically rotate the 3D part images, as well as zoom in and out on the molding issues the system has flagged. "It lets users locate the issues much more intuitively than on a static 2D image," says Brad Cleveland, president of Protomold. Once you locate the issues, you can fix them by tweaking your original part design.

While Cleveland would certainly like to have you place an order after trying ProtoQuote, the system does return the same 3D design-for-moldability report whether you purchase any parts or not.

See a demo of the new 3D capabilities. The demo currently works only in Internet Explorer and requires a small, fast download to view the 3D graphic.