- 1). Mix 1/4 cup of lemon or orange oil with a cup of linseed oil to make an oil-based paint thinner.
- 2). Mix in small amounts with your paint, such as a tablespoon at a time. Make more thinner as needed.
- 3). Mix a few tablespoons of white vinegar or rubbing alcohol at a time to thin out acrylic paint. Acrylic paint rarely needs to be thinned, but if it's been sitting for a long time and has stiffened up due to water evaporation, you can reinvigorate it with a thinner.
- 4). Mix 2 drops of dishwashing liquid to a quart of water without making it soapy. Add a few spoonfuls at a time to the acrylic latex paint to thin it out.
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