Coated Test Specimens: Coated surfaces shall meet testing requirements as specified for thickness, rapid deformation (impact) flexibility, adhesion, gloss, and cure. Testing shall be performed on test sample specimens processed with each run as described in this specification, and on production parts as often as deemed necessary to ensure specification compliance. A minimum of three (3) test specimens of material shall be coated with each run processed in any powder material color, or chemistry. Test specimen size is 3″ x 5″ 16ga. and will be manufactured from stock common to the components. Test specimens shall be processed through the entire finishing process from pretreatment to powder application and curing.
Powder manufacturers and applications are well equipped to assist in selection of the most appropriate powder for a given application and may also assist in establishing specifications where none exist. The performance-driven approach starts with simple questions such as:
Critical needs should be well defined and well thought out, without yielding to the tendency to concentrate too heavily on single properties. By utilizing these two simple questions, it is possible to satisfy the specific performance objective and not over-specify or over-engineer the product, which tends to add cost and obscure the real objective.
Class A– Finish demands the most consistent gloss, fewest defects and highest smoothness and minimum batch-to-batch color variation.
Example- P C boards other electronics and automotive appearance finishes.
Class B– Finishes similar to A but more easily achievable quality objectives. A large percentage of decorative powders are in Class B and include decorative shelving and light fixtures.
Class C– Generally prescribed for non-appearance parts and therefore have reduced appearance requirements but will require good barrier properties. Applications include engine blocks, reinforcement bars for concrete and other construction needs.
Assign physical property quality standards with end-use in mind.
Generally the higher the coating classification, the higher the cost. Assign finishes’ standards realistically.