Hopefully you want to clean immediately, the paint hasn't dried, and the brush is of good quality.
I have always used turpentine for years, but there are more expensive formulas available.
If it the paint has hardened there is no magic formula, regardless of the hype.What is best way to clean a paint brush after using enamel paint?
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Since I really haven't answered your question, it is not necessary to give me any points. Regards.