Please Contact Avion Metal Works of Florida  so we may help and inform you of the impor- tant various aspects of purchasing aluminum,wrought iron, and metal products. For your information Poor finish: Non-marine grade castings and finishing application Best finish: Marine grade castings, proper preparation, and quality finishing. There are many steps necessary to providing a good, hard, coherent coating to aluminum castings. These steps include proper cleaning and rinsing,  degassing, and proper curing of the coating. However, even if these steps are followed, sufficient evidence from on-site inspections and field reports  suggests that another step is necessary on your part: using marine grade base material. The marine grade approach offers added protection for long life  and better looks. Also: See our article’ ‘Wrought Iron or Aluminum. The Choice’.  The rapid flaking and peeling of coatings from aluminum castings in a severe weather environment or normal slower deterioration in a milder environment  can be resisted with the proper selection of marine grade base metal aluminum casting to resist corrosion and improve coating performance. This scroll casting is not marine grade. It shows severe white corrosion after only 18 months in its ocean environment in Sarasota, Florida. No coating remains. Flaking and peeling occur on regular aluminum because air penetrates  through the coating and corrodes the base metal. The devastation of  the coating can occur rapidly when the product is next to the ocean.   The scroll casting pictured at left has been near the ocean only 18  months and shows almost complete disintegration.  POOR: Corrosion on non-marine grade castings. Typical corrosion of  non-marine aluminum castings is shown at left. The ball cap below left,  has been near the ocean for four years and shows corrosion on the  corner edges where only a thin layer of coating might have been  applied. This edge with a thin coating enables the salt air to penetrate  here first and begin the corrosion peeling action. The root cause of the white chalk aluminum corrosion is residual amounts of copper creating  a galvanic reaction with the aluminum base material.  BETTER: Corrosion on marine grade casting. Pictured below is a  handrail installed near the ocean in Palm Beach, Florida. For eight  years the castings have been directly exposed to the wind and spray of  the ocean. However, they are still shiny and coherent. This shiny and  coherent surface indicates no galvanic corrosion has occured as the  marine metal has successfully resisted the salt air.  This 2" ball cap is not marine grade. It shows chalk corrosion and flaking (starting at corners) after four years on the Indian River in Vero Beach, Florida. Yet there’s even something better then powder coating! You want great looks and long life from your new outdoor wrought iron, aluminum metal doors, fences, gates, driveway entrances,  and balcony railings. If you live in a severe weather environment, or near the ocean, special  care and preparation must be applied to that product. To avoid deterioration, first, a ‘Marine  Grade Casting’ is necessary... which is a special mixture of various metals for added protection.  Unfortunately, some wrought iron companies will not make you aware of this to keep their  material costs low. Avion Metal Works of Florida includes ‘Marine Grade Casting’ as a standard  practice. Please read on for important information.      This flower panel in West Palm Beach, Florida, shows flaking because of a poor coating job. But its marine grade castings are still shiny and coherent after eight years. This aluminum rail with marine grade aluminum cast collars also shows a coherent coating in excellent condition after three years on Florida's Intracoastal Waterway. BEST: Corrosion on marine grade D castings. A recent on-site survey of many copper-free marine grade castings that have been on the ocean up to 3½ years shows the excel- lent results of combining marine grade castings with  coating applications. "Marine grade castings!" A pictorial survey of eight case studies suggests that using marine grade castings and a special application finish to avoid degassing results in long lasting beautiful aluminum castings, even in harsh salt water environments "Aluminum Gate, Fence, & Railing Finishes!" Corrosion on aluminum These spear points illustrate the coherent coating of marine grade castings in excellent condition after one year on the beach.