CAD data exchange remains a challenge for designers and engineers during the product development stage and in the data turnover to manufacturing. Among the many 3D CAD systems there is limited data transfer capabilities that retain native feature functionalities. Accordingly CAD data is routinely transferred between CAD platforms using IGES (Initial Graphics Exchange Specification) and STEP (Standard for the Exchange of Product model data) formats. While these exchange tools provide for generally good data transfer they do not transfer feature creation data and are thus inflexible for modification. While CAD publishers recognize this as a problem and have tried to address it; to date there has been poor result in translating anything but primitive geometric forms which are comprised of planar, cylindrical, revolved, and spherical surfaces. Parts that require splined curves and surfaces remain problematic to transfer from one CAD platform to another. The reason for this is that primitives are defined mathematical different from those of complex surfaces. While primitive geometries consisting of planar, cylindrical, ruled, spherical, and revolved surfaces and can be defined by unlimited discrete mathematical coordinates, those that are defined using spline surfaces require polynomial equations with interpolation to transition between defined curvature patches within the surface curvature network. The interpolation aspect of surface data translation is the basis of the popular commentary on IGES translation which is that IGES is an acronym for "I guess." http://www.cadmodels.biz/import_3d_cad_data_exchange_and_data_repair.html

Injection molding of plastics is one of the most cost effective processes for manufacture of parts in volume. While mold costs can be significant, amortization over many parts can make the overall cost of injection molding highly competitive with other manufacturing processes. The wide range of available polymers multiplied by the huge array of specific blends offer a tremendous range of physical, thermal, electrical, and chemical properties. Engineering plastics, classified by mechanical properties such as stiffness, toughness, and low creep, increasingly replace metals on a cost and performance evaluation.

Designing for injection molded plastics requires planning. Too often parts will be presented to a molder or tool designer late in the product development process only to be confronted with feasibility issues. If that happens the developer faces decisions to rework part designs or to face higher tooling and part costs. Leaving design for manufacturing and assembly (DMFA) considerations until late in the development program is a common mistake the misses out on optimization and disrupts the transition to manufacturing.

Planning begins in preliminary design. Some will argue that consideration for manufacturing early in the program will inhibit creativity; the reality is that it does not if perspectives are kept in balance. In fact design committee often err in committing to a design that later reveals feasibility and cost issues. While designers and engineers need to be free to brainstorm potential solutions, taking time to evaluate for manufacturing options is vital to assume a successful program. http://www.cadmodels.biz/3d_cad_design_for_injection_molded_plastics.html