Drafting and Design Errors

Drafting and design errors include inappropriate rib heights, boss drafts, and the other errors of design or design specification that can make the part unmanufacturable. Additional problems included in this category include interference with the customer's sheet metal. The customer here is actually another in-company division, and the sheet metal is the formed surface of the automobile. Errors are discovered in the process of fitting the molded part with the rest of the car. The common factor in this category is that, although information was available, human error on the part of part designers occurred.

This category of drafting and design errors ranks highest in terms of quantity and total time. Many of these errors are repeated time and time again, like a misspelled word, and are exactly the types of errors appropriate for a design advisor. Furthermore, these errors are usually specific to a feature of the part indicating the further appropriateness of a feature-based evaluation.

Quite simply, feature-based manufacturability evaluation addresses problems with drafting and design as well as sinks. To some extent, it should handle venting issues as well. Other major problems with heat problems and lighting involve assembly or numerical issues which are beyond the scope of DFM.