The finish of the die cast tooling will largely determine the surface finish of the die cast part. This means that a highly polished and finished die will offer great casting parts. Surface roughness of the most of the die cast tooling makes it easy to offer matte finish parts. Some of the decorative die cast parts and components, however, need the application of external surface finish.
Die cast designers and manufacturers can plan for the surface finish of the parts right from the die design phase. Die cast finishes can be classified into five categories as discussed below.
Utility Grade
This is the class of die cast finish, which does not have any cosmetic requirements for the finishes. This grade allows for rubs, cold shrubs, lubricant buildup, porosity, and many other imperfections. The finish of the end product can be as cast or the client can choose to have a protective coating on the end product like chroming or anodizing.
Functional Grade
This grade of die cast finished product allows for surface imperfections that are removable by spot polishing or painting. The client can choose decorative coatings like enamels, lacquers, chemical finish, and plating or polished finish for the finishing of the final product.
Commercial Grade
This is the grade of die cast finished product that allows the removal of surface imperfections making use of finishing methods that are agreed to by the client. For the final finish of the product, the die cast design can call for structural parts in the high stress areas of the product. Other options available for final finishing are zinc plating, electrostatic plating, and using transparent paint.
Consumer Grade
This grade will not have any objectionable surface imperfections. If the finished product is rejected due to presence of surface imperfections, the client can find a course of action by discussing with the die caster. In addition, the designer may use decorative parts for the end product based on the requirements and specifications.
Superior Grade
This is the finish that offers superior finish to the end product and applies to only a limited area of production. In this type of die cast finishing, the end product may have gasket areas or O-rings.
These are the different die cast finishes or cast surface categories. However, these categories do not apply to the machined surfaces, meaning that the die cast designer should mention about the finished machine die cast surfaces in the design drawing.