Tip: Save Your Waste White Spirit or Paint Thinners and Reuse
Many of you probably use the newer type of solvent free, water based acrylic paints out of a concern for the environment. These paints are replacing oil/gloss paints as a protective coating for timber and metal. Personally I don't like them because I find the coating seems to be thinner and tends to peel more with time. However that may be due to bad preparation on my part of the original underlying oil paint coating. Anyway traditional oil or gloss paint is thinned with white spirit (mineral spirit) or turpentine and this is also used for cleaning brushes after use. However after you rinse the brushes several times in spirit, don't throw away the waste. Store it in a container e.g. a 2 litre or quart plastic milk container (remove original label, label the contents and keep out of the reach of young children!). Over the next few months the solids will come out of suspension and settle to the bottom where they tend to bind together. Then you can just decant off the clear spirit and use it again. Use it for cleaning brushes, not thinning paint as it can be tinted or contain other solvents. You can do this indefinitely.
Image: Sweetie candykim, Creative CommonsCC0 1.0 Universal Public Domain via Wikimedia Commons - https://commons.wikimedia.org/wiki/File:White_spirit.JPG