I rinse my paint brushes well after each session, and frequently as I paint. I don’t always remember, though, to clean them in soapy water afterward. I seldom have an official “end” to a session, I tend to think I’ll come back and finish up a few more things first.  At 3:00am this morning, I discovered that paint had built up in my favorite No. 8 chisel blender.  I used to toss them when that happened, but discovered an easy fix and some helpful links are below. Basically, after each session I clean the brushes in soapy water. If paint is built up, I can soak them a few hours in either Murphy’s Oil Soap or hand sanitizer, then rinse well.

Helpful links:
How to Get Dried and Hardened Paint Out of your Brushes
How to remove dried acrylic and oil paint from brushes
Clean Stubborn Acrylic Paint out of your Paint Brushes