Wooden paint trays have been utilised by professional artists for centuries. However, difficulties cleaning the wood surface of the paint trays often lead some painters to abandon the idea of cleaning altogether. The manufacture of plastic paint trays has made tough palette cleanups a thing of the past. Most plastic paint trays are made of a smooth, durable resin that does not require heavy scraping and scrubbing to remove wet or dried on paint.
Remove all excess paint from the plastic paint tray. Large amounts of leftover paints should not be poured down the sewer drain, sink or toilet. A much safer way to dispose of paint is to pour it into a bucket. You can put leftover latex and acrylic paint together in the same bucket. Add a paint hardener to the bucket when it is almost full. The paint can then be removed from the bucket, wrapped in newspaper and brought to the tip.
Place the plastic paint tray in the sink. Turn on the tap and rinse the paint tray with warm water. Allow the water to run over the plastic paint tray until it runs clear.
Add a few squirts of dish soap to the water if there is still paint remaining on the plastic paint tray after you rinse it. Use a plastic scrubby sponge to help clean off any stubborn paint.
Allow the plastic paint tray to soak in a sink of warm, soapy water overnight. When you wake up in the morning, simply give the plastic paint tray a rinse and allow it to air dry in a dish rack.
Allow the paint to completely dry on the plastic paint tray. This is another option for cleaning plastic paint trays. However, the effects are not immediate, and you will need to wait before using the plastic paint tray again. If you allow the paint to sit until it hardens, most acrylic and latex paints can simply be peeled off of the surface of the tray, rendering it ready for use again.
A piece of clingfilm can also be placed over the plastic paint tray, for a quick and easy cleanup. Simply dispose of the paint when you are done painting, lift off the clingfilm and throw it away.
Never use a plastic paint tray for oil painting. Turpentine solvents will erode the plastic. Unfortunately, oil paint artists must still continue to use wood or glass paint trays.
Do not put plastic paint trays in the dishwasher. If your dishwasher gets too hot, it could melt the plastic.