Hot answers tagged cleaning
I use pure Eucalyptus oil. It works wonderfully. Keep in mind that if you are using it on LEGO, it will also remove the original printing (but won't harm the plastic itself), so I wouldn't recommend it in that case. But other than that Eucalyptus oil can remove marker, paint, glue-residue, and all kinds of gunk much better and faster than products like ...
I've used a dry erase marker, over the permanent, to remove it from a white board. I don't know if that'd work on Lego or not.
I know it's not the most cost-effective way, but I used to use gasoline on a rag to remove a lot of markings on plastics of all kinds. It won't warp the plastic when used sparingly on a rag. The only downside is that it may "smear" the marker, depending on the kind of marker that was used.
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