revive paintbrushes: If you have old, hard paintbrushes, don’t throw them away! There is a quick and easy way to revive them. All you will need is vinegar and soapy water.    First, soak nylon paint brushes in hot vinegar for up to 30 minutes. After soaking, wash them with hot, soapy water. They will be as good as new, and the process is a lot cheaper than buying new paintbrushes.