Q. We have an aluminum casting from which we need to remove powder coat. We have investigated sanding and chemical, but the heat process may have a very negative impact on the part shape. What are your thoughts? L.M.
A. Heat stripping of organic and powder coatings is a well-established process. To minimize the potential for parts to distort, it would be important to use a relatively slow heating and cooling rate. Most suppliers of stripping ovens would be willing to perform tests with sample parts to demonstrate the capability of their process.
Various types of media blasting methods are very effective for paint stripping as well. There is a wide assortment of media available depending on the material and geometry. Plastic media blasting will make use of media that is available in a wide variety of geometries (long/angular, shorter/rounder) and various hardness in order to effectively remove the coating without damaging the substrate. Bead blasting and wet blasting techniques are also successful at powder coating removal.
Infrared cure is gaining increased attention from coaters as a result of shorter cure cycles and the possibility of smaller floor space requirements when compared to convection oven curing.
Powder coating is one of the most durable finishes that can be applied to industrial manufactured products, and offers excellent corrosion protection and is very safe because of its lack of volatile organic compounds.
Question: What methods are available for removing cured powder coatings, and what are the pros and cons of these methods?