DFM is often viewed as a body of useful information for improving the manufacturability of a part but without a step-by-step method. DFM guidelines are a primary resource providing guidance on how to improve the manufacturability of a part for the particular manufacturing process being used. One major problem with these guidelines is that there is not a consistent format for organizing them and understanding specifically what they are trying to accomplish. A standard DFM guideline structure would provide a consistent context for better understanding them. To this end we built a template, in the form of a taxonomy, based on variable cost of the part. We define the variable cost of the part to be comprised of its material, labor, and utility costs and for each of these, we defined factors that influence these costs. We claim that this template can provide a framework for organizing and presenting DFM guidelines in a context that the engineer can use in a more useful way. To provide more confidence in our template, we pursued a validation process based on the Content Analysis technique which is a way for making quantitative inferences about qualitative data, such as DFM guidelines. We used this technique to refine and validate the template which is presented in this paper. To provide further evidence and demonstrate the template’s usefulness, we provide two examples: the guidelines for electromechanical machining and guidelines for plastic injection molding.

A design for assembly worksheet is introduced that enables flexible accounting of assembly activities, especially welding. Welding activity is broken down into a variety of pre- and post-welding activities and the time penalty is estimated. This weld estimate is included into the traditional worksheet. This approach is especially useful for large complex products that are produced in small volumes where a significant portion of the assembly activity is through welding. These types of products often pose challenges for employing DFMA techniques cost effectively because of the increased engineering cost, divided among relatively few products, outweighs the potential benefits.