Burns on any household item can be difficult to remove. Burn marks on bathroom sinks are caused by a variety of things, including lit cigarettes, candles and heated hair styling devices, such as curling irons. Although deep burns in plastic require more extensive repair, you can remove superficial burn marks using an abrasive cleansing product. Removing the burn mark takes a little work but will restore the sink to an attractive condition.
Pour 1 tsp of liquid dish soap onto the burn mark, and scrub it with a damp scrubber sponge to remove some of the discolouration, as well as any substances, such as candle wax, from the sink surface.
Sprinkle a powdered cleaner over the entire surface of the burn mark, and scrub it with the a damp sponge. Any sponge is effective, but melamine foam sponges work the best.
Allow the cleaner to sit on the burn mark for two to three minutes, and scrub it with a scrub brush.
Wash away the cleaning residue with clean water.
Press a piece of fine grit sandpaper, such as 200-grit, against the burn mark and sand it down until you have removed the rough edges of the burn mark. Be careful to only sand the burn mark and not the undamaged section of the sink.
Dip a wooden craft stick, or other small flat item, into the jar of epoxy filler, and fill the depression until it is slightly higher than the surface of the sink. Scrape the clean end of the stick horizontally over the epoxy to level it out and to scape off the excess.
Allow the epoxy to dry for the amount of time recommended by the product packaging.
Apply paint to the surface of the epoxy using a small paintbrush. Choose a paint colour that closely matches the colour of the sink to best disguise the repair.