How to Handle and Eliminate Powder Coating Defects

Q. What is an efficient and effective strategy for eliminating product imperfections and defects in my powder coating operation?

A. While we all strive to provide the best possible product and service, we know that things do not always turn out as planned. This is obviously true for every business and shop. Manufacturing is a human endeavor, provided in an environment subject to constant change. It is planning and organization which give us the best opportunity to overcome challenges and produce quality products. The important thing in finishing and coating, as in any enterprise, is to have a regular and organized plan to find the source of any error, provide a solution for the customer and implement lasting change.

Finding the source of the error begins with an action report. The report should outline any customer objections and details regarding the defect or imperfection. Analysis must then be conducted to ascertain the source of the problem, which may be related to human error, equipment failure, atmospheric conditions, manufacturing deficiencies or any combination of these. Next, a plan of action can be developed to correct the issue, with a timeframe set for resolution. Testing should be conducted to determine the effectiveness of the solution, and a schedule adopted to monitor and manage the improvements made. Further action should be planned to make certain the solution adopted becomes a permanent part of production. Because this corrective plan of action is regular and part of the overall production organization, the inevitable error becomes an improvement opportunity rather than a stumbling block.

Two recent examples show how we have been able to find quick and effective solutions to common and less common issues.

A customer returned parts due to heavy and inconsistent coating. An action report identified the problem as resulting from the Faraday Effect, a common occurrence in powder coating, caused when charged powder does not flow fully to a tight area because electricity will not readily follow the more resistant path. These tight areas can be covered effectively by adjustment of the volume output at application and by spraying at an indirect angle. The most immediate plan of action was to utilize these techniques more efficiently. The most effective plan for permanently eliminating the defects was additional and ongoing personnel training, with the work being continually monitored to ensure that the customer was provided parts with a smooth and durable finish.

In another case, panels were returned due to a color shift in the finish. The action report identified a problem in the powder obtained from the manufacturer. Consultation with the manufacturer resulted in a tightening of the color specifications. New panels were coated with the new powder and all matched the master panel. The panels continue to be monitored and continue to maintain color.

Powder coating provides a clean, smooth and durable finish to parts and equipment. A regular and strategic plan to permanently correct occasional defects or imperfections will ensure that customers continue to receive the finishes that expert and high-quality coating affords.