Corroded/Tarnished EV3 steel Balls - How to clean?

[DrJB]

I've got few of those and over the span of 2 years (at most), these do not look as clean/polished as when I bought them.

Anyone else experienced this and knows how to clean them?

I keep mine individually in a ziplock bag.

[Saberwing40k]

WD-40, my friend. But, using these will obviously scratch and dull them, a little bit. So, if it's that, I don't think there is anything that would be worth your time, and effort. So, I think you should have left the part about rust, unless there is actual corrosion.

[Balrog]

I thought those balls were stainless steel?

[MajorAlvega]

My two LEGO balls are still shiny but I have other two ex-mouse balls (same size, perhaps not quite the same grade of steel) that became dark.

Try mild vinegar or a baking soda past and a soft tooth brush.

[BusterHaus]

CLR will probably do the trick.

If you do use WD-40, wipe it off after cleaning the balls. It is not a grease and can make rust spots on hardened steel.