If it is aluminium corrosion it's simply because of damp/air .. just as steel corrodes or discolours. If your trim is aluminised inside a plastic strip/trim it may be discolouration as bonding of layers weathers/breaks down.If it is aluminium corrosion it's simply because of damp/air .. just as steel corrodes or discolours. If your trim is aluminised inside a plastic strip/trim it may be discolouration as bonding of layers weathers/breaks down.
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Small white specks suggest aluminium corrosion.
Try rubbing them with a cloth with WD40 on
If it is aluminium corrosion it's simply because of damp/air .. just as steel corrodes or discolours. If your trim is aluminised inside a plastic strip/trim it may be discolouration as bonding of layers weathers/breaks down.