Paint Peeling Problem
Question: I am the manufacturing engineer responsible for painting in my plant.
I am the manufacturing engineer responsible for painting in my plant. We are experiencing paint peeling problems at the seams on cabinet panels. We suffer the same problems on re-paints. This is near the point where we hang the parts and the flanges sit on the inside, facing away from the camera. Can you help me in pinpointing the problem? Thanks! K. M.
You have already pinpointed the problem, K. M. I’ll help you solve it. Seams in painted products can cause problems. If there are oily soils present on the sheet metal, they are hard to remove from inside the seams, because it is hard to get alkaline and detergent cleaners into them. Therefore, oily reside is left in them. When you paint the panels, the paint bridges the gap, which according to the photographs you attached, looks to be pretty wide. Since paint won’t adhere to air and there may be oily soils on the seams, the paint flakes or peels in that area. On repainting, the same thing happens. The oily residue, which was entrapped, will seep out causing adhesion loss and subsequent paint peeling.
One cure that comes to mind is to fill-in the seams using a body putty, that is compatible with your paint. This will not only seal the seam, but will also give the paint something to grip. I know this is a labor intensive extra step, but it may be more cost effective than repainting.
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