Working on a project for making a switch panel for a boat. The final outcome is planned to have a white panel with black engraved letters. I am having problems with the white powder coat giving me blemishes. There are some brown spots around the lettering and some pin sized bubbling. I’ve tried cleaning and re-preping the aluminum, but its still having problems. I have been using Eastwood Pre-prep. I am attaching some pictures.
https://imgur.com/a/qP0WO
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