I bought a nice Wooster Pro nylon brush to use for applying water-based polyurethane to some projects. After the last application, I forgot to wash the brush and it has since dried and hardened. I can peel the bristles apart but they're still very stiff and they remain stuck together in small clumps.

Is the brush destined for the trashcan, or is there a way that that I remove the dried polyurethane from the bristles to salvage it? It's a $15 brush, so it's not really worth anything beyond an easy fix.


It will most likely never be like new again but you could soak it in a jar of paint thinner over night. Then wash it out with dish soap and warm water.

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