253: Using Sun Oil to Oil Up a Canvas

A VERY useful medium I use lately is sun oil mixed with about 1/3 Gamblin Alkyd Gel (or G-gel). In the video below I give a very brief demo of how to mix and apply the resultant mixture.

Sun oil is easy to make and requires no specialized equipment. Start by buying a quart of linseed or walnut oil

Walnut oil takes longer to make but will be clearer, having less amber tone. Walnut oil will also dry slower. Pour the oil into a glass casserole pan. I use a pan that measures about 12″ x 18″ and is about two inches high. Add oil until it stands about 1/2″ to 3/4″ in the pan. Place the pan in direct sunlight.

Then place a piece of glass over the top. The glass must completely cover the top of the pan. To insure I have a gap, so air can circulate, I take four US dime coins and stick a small bit of kneaded eraser on each side. I then place the coins, kneaded eraser side down, in each corner of the pan. Then I set the glass pane over the pan. The coins will keep the right gap and the kneaded eraser bits will insure that the coins don’t accidentally drop into the linseed oil.

Place the pan with the glass on top in a place where it will get sunlight all day. The sun will heat up the oil and will develop a film on top. Be sure to stir the oil once or twice a day so the film doesn’t actually dry. As you mix the thick oil on top into the thinner, lower layers the overall mixture will get thicker with each passing day.

In about ten to fourteen days you will have a mixture that is quite thick. Add more days to thicken to your personal preference. I like to get the oil a bit thicker than I need so that when I add the G-gel, which will be slightly thinner, it will be about the thickness of tubed paint. I add the G-gel to prevent the melting that is so common with Linseed and walnut oil. Pure oil will seem like it is staying put on your canvas but in a few hours pure oil will allow the next layer of paint to slide downward.

I paint this basically clear mixture onto my canvas when I need to add thick layers of new paint over a dried layer. This technique will allow for wet-into-wet painting even though the bottom layer of paint is dry.

Brad Teare –October 2015

Buy Brad’s Art Online Today

Updated: 17th January 2022
etsy store