How do you remove paint from an ice-cube tray so that you can use the ice-cube tray for making ice again?
Any ideas?

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but if you really want to use them then I'd just fill with water and freeze then pop the cubes out. This might remove the paint but you might have to do this several times.
YOu might also try spraying WD40 to see if it lifts the paint. You can remove the WD40 with soap and water.