Chemistryâwhich I took fifty years agoâwas my worst subject, and now I spend much of my time thinking about it. Life always gets the last laugh.
âHow long does oil paint take to dry?â is one of the most frequent questions Iâm asked. I made this video to answer the question. Itâs part of The Heart of the Painting, step six of Seven Protocols for Oil Painters.
For those of you playing along at home, I recorded the video for step seven (about final finishes and flourishes) before I left for Britain. Laura is editing it right now. When itâs done, youâll be able to learn to paint step-by-step at your own pace and youâll no longer need me.
I plan to edit this material into book form when Iâm done. No âhow to paintâ book can possibly be as complete as these interactive courses, but a book is easier to curl up with.
So, how long does oil paint take to dry?
New painters want to know if they must let their paint dry between layers. Itâs not necessary if you adhere scrupulously to the âfat over leanâ rule. Keep those bottom layers thin and you can paint right into them.
Paint is a simple material, just pigment particles suspended in a binder. So why do some paintings break down? Much of that is down to experimenting with additives. Laying new materials in a pool of drying oils is a recipe for long-term decay. Our museums are full of 20th century paintings with premature cracking. In oil painting, conservative skepticism is sensible.
Ignoring the âfat over leanâ rule is another cause of failed, cracking paintings. The most common solvent today is odorless mineral spirits (OMS) which breaks down the oil and then evaporates. In the bottom layer, that can leave a touch-hard finish in as little as half an hour. That surface can easily be broken if you need to edit. However, in the squishy top layers, OMS can wreck your painting.
I wish someone had told me this when I was younger. I struggled with paintings that looked great when wet but grey when dry, and which aged terribly even in the short time I knew them.
Oil paints donât dry, they absorb oxygen from the air to harden. Whatâs oxidizing isnât the pigment but the oil between the pigment particles. Different pigments have different particle sizes, so some colors dry faster than others. Iâve outlined the dry times in the video, but the most important one to remember is titanium white, which is a slow dryer. Thatâs one reason it doesnât belong in your grisaille.
The âfatâ in paint is siccative oil, which in most cases is linseed oil. Itâs so harmless itâs edible. The downside of linseed oil is its tendency to yellow over time, so other oils, like walnut or safflower, have been substituted. They, sadly, are more prone to cracking. Itâs an imperfect world, isnât it?
Alkyd paints and mediums are made from oil-modified resin treated with alcohol and acid. Their main advantage is their dry time. They can give you a touch-dry surface in 24 hours. You can use an alkyd medium with traditional oil paint. The granddaddy of these was Winsor & Newtonâs Liquin, developed in the 1960s. In general, alkyd resin doesnât hold as much pigment as traditional oils do. I donât use them because I generally seek a slower dry time, and Iâm put off by the smell.
How long does oil paint take to dry? It depends on many factors, but as long as you follow the âfat over leanâ rule, itâs not important.
Iâm in Britain on another lovely, long, blister-inducing hike. Iâve turned my phone off and while Iâm gone, Laura will be running the office. Just email me as usual if you have questions or problems registering for a class or workshop. (Who am I kidding? She fixes all that stuff anyway.)
Reserve your spot now for a workshop in 2025:
- Canyon Color for the Painter, Sedona, AZ, March 10-14, 2025
- Advanced Plein Air Painting, Rockport, ME, July 7-11, 2025.
- Sea and Sky at Acadia National Park, August 3-8, 2025.
- Find Your Authentic Voice in Plein Air, Berkshires, MA, August 11-15, 2025.
- Immersive In-Person Fall Workshop, Rockport, ME, October 6-10, 2025.