How to Varnish an Acrylic Painting
Are you wanting to varnish your acrylic paintings?
Today, I will show you the best way to apply varnish in a way that maximizes longevity and protection against damage from the sun or ultraviolet rays. The first step is to use a gloss medium and varnish to seal the painting. I use the brand Liquitex. This will provide a layer between the actual paint and the top coat of varnish that we'll spray on later. This extra layer of protection will allow you to retouch the painting years down the road without damaging any part of the painting underneath. It is called an "isolation coat."
To apply the gloss medium and varnish, use a big paintbrush and cover the entire surface, ensuring that you check in the light to see that you've covered everything. If you want to imitate the brush strokes in your painting, you can do that to provide a little bit of texture and keep the feel of the brushstrokes over on this outer layer.
After one coat, let it dry completely, and then apply a second isolation coat in the same way. You can let it dry naturally or use a hair dryer to quicken the drying time.
You will notice the surface of the painting will look shiny in the light. If you're happy with the results, you could be done.
However, to add extra protection against the sun's rays, you can use a spray varnish. I use Winsor & Newton Artists' Gloss Picture Varnish.
To do this, go outside and use the spray varnish to apply a nice even coat, holding it back about 5-7 inches. Ensure you have a protected space and aren't inhaling fumes. You will want to do one coat horizontally and one coat vertically to ensure full coverage of the whole painting.
The spray varnish will create an extra durable coat, and it will dry fairly fast, usually taking about 20 minutes to be completely dry.
Your painting is now fully varnished and ready to go!
Note: When I don't have a lot of time I skip the isolation coat and ONLY use the spray varnish. I still feel confident that it has adequate protection just with this varnish.
