Design is everything. It affects the manufacturability of a part, and often the usability of the end product. Every mold maker and molder would agree that flawed designs result in less than optimum molds and molded parts. Despite that fact, design remains the most problematic element of the mold building process for original equipment manufacturers and mold makers. And technology may or may not hold the key to these problems.
``It amazes me how many [OEMs] have insufficient engineering talent that can design plastic parts,'' said Christopher Singleton, project coordinator and sales manager for Conestogo Plastics in Waterloo, Ontario.
``Most mechanical engineers can build a suspension bridge, but they have no idea how to design a snap-fit, plastic part,'' he said.
Michael T. Hudalla, a partner in Isometric Tool & Design Inc. in New Richmond, Wis., expressed best what many mold makers feel. ``We need to be given more responsibility for the tool de-sign,'' Hudalla said at a recent meeting of the American Mold Builders Association in Corona-do, Calif. ``Many times customers want us to design a mold a certain way that we know won't work, but they say do it anyway. So we do, then have to make changes later.''
That is the primary reason mold makers want to be invited into a project in the concept stage of product development. The best time, said Singleton, is ``about two meetings after marketing tells management that they've decided to go with the new product.''
Mal Bass, president of Indian-apolis mold designer and maker Competitive Enhancements Inc., said, ``Projects where key players are involved at the earliest possible time are projects that have the most success.''
Although early involvement is the ideal, it is still not the norm, say many mold makers. Annette Lund, sales and marketing manager for Diversified Plastics Inc. in Minneapolis, said only a few of her firm's customers call them in during the concept stage.
``More often they'll draw up an idea and send it to us in blueprint form for our input,'' Lund said. ``Sometimes it's more difficult to make changes once it's drawn on paper, and has a part number and everyone's blessing.''
Singleton agreed. ``There may be all kinds of flaws in the design, but if its been signed off and approved, making changes at that point is difficult.''
Not only can mold makers point out the feasibility or manufacturability of an idea, they often can give the customer a more realistic cost for completing the project. Singleton said that in at least one case, a customer had to double the amount initially budgeted for a new product.
Additionally, finding design flaws before they are cast in steel is most cost-effective. That is where technology comes into play. Diversified's Lund said that sometimes problems with a part are not discovered until after the mold is started and steel is cut.
To eliminate that, Diversified uses CadKey software, which Lund said is compatible with Pro/E, the software many customers use. Transferring part designs electronically lets Diver-sified's engineers and its customers' engineers simultaneously look at the drawing and point out problem areas and make changes.
However, Isometric's Hudalla believes there continue to be too many changes. ``Concurrent engineering is nothing more than a way to accommodate the never-ending [engineering change orders] and it's getting worse.''
Although new technology provides methods for improving design capabilities, it does not always solve the problems.
``In fact, new technology is constantly showing us deficiencies in how we are doing things and forces us to continually increase what we know about the technology and how to use it to maximize our manufacturing,'' said Dennis Nealon, president of Arizona Precision Mold.