How do these three words make the difference between fully protected galvanized steel and a surface vulnerable to corrosion? Richard Besant, Powdertech Corby gives us the low-down on ‘designing with the finish in mind’.
Richard explains, “Before your component even sees a powder coater there are simple yet critical design decisions that will ensure the protection offered by galvanizing and powder coating is the most effective it can be. If these are attended to in the early stages, the galvanizing and high performance powder coating will offer protection for 35-40 years. Correct venting and drainage points for both galvanizing and powder coating must be included in the fabrication design to ensure that the finished part sinks fully into the molten zinc during galvanizing and into the chemical pre-treatment prior to powder coating and also drains completely on removal from both processes. Sharp edges should be rounded off to avoid localised thinning of the coating for any finish, zinc, paint or powder coating. Welds need to be checked to ensure that chemicals will not become trapped and then leach out during finishing operations. There are other considerations to be borne in mind too, such as the metal’s final site. For marine location, narrow gaps and blind crevices should be avoided and the surfaces should be free draining and easy to clean.
It also makes sense to clearly identify the ‘seen’ faces of the design so that suspension points (for jigging) can be located in positions unseen after installation. We always advise our customers to ‘Design with the finish in mind’.