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I have some brushes that areI have some brushes that are over 20 years old. The trick to that is, making sure you clean ALL of the paint from the brush. EVERYTIME. To do this,place the whole brush in clean water(or thinner),turn upside down, and bend the bristles, forcing the water through the ferrule until there is only clean water. This may take a few buckets of clean water, but it is well worth it. Use a wire brush to remove any dried paint from the bristles. Making sure that you go from the ferrule to the tips of the bristles. NEVER go sideways with the wire brush. Let air dry and then wrap back in original cover. If the cover is lost or wears out. Use paper without ink in it. Masking paper works well. With use, your brush will actually take on it's own personality.

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