Welcome back to my series on using the Flemish method of oil painting. If you missed any of the previous posts in this series, or if you would like to review them, links are provided at the end of this post.

Since it takes at least a week for the umber layer to dry thoroughly and since some of you may be following along, making your own paintings, I thought I’d take time this week to answer five of the more frequently asked questions.

5 Questions About the Flemish Method of Oil Painting

The Flemish Method 5 Questions Answered

What Makes the Flemish Method Work So Well?

The Flemish method of oil painting is based on the premise that light travels through paint, strikes the canvas or panel, and bounces back out again. Every layer of paint influences the quality of the light in some way both in color and in intensity. The thicker the paint, the less the light bounces and the flatter a painting might appear.

The thinner the paint, the more light gets through the paint, and the deeper a painting may appear.

Why Paint Every Layer if You Paint Over Them Anyway?

Every layer from the imprimatura through the final detailing layer affects the final painting. If you painted the same painting once going carefully through every step and painted another version of it skipping or combining some, there would be subtle differences. Most people probably wouldn’t be able to tell you why, but they would prefer the “full-up version.”

Yes, you can leave layers out or combine them to speed up the process, but you will lose something in the process. In some cases, the trade-off may be worth it, but the best paintings are usually created without shortcuts.

A Personal Story

Back in 2003, I had to paint a collection of horse racing images for a show being held in conjunction with that year’s Kentucky Derby. This painting was one of that collection.


The horses and jockeys were easy to paint.

The background, no way. I tried a number of things ranging from a blurred landscape to colors reflecting the colors in the racing pair. Nothing worked.

My husband suggested pink. I shied away from that like a racehorse shying from blowing paper. Nobody put pink backgrounds on horse paintings. Nobody.

I kept trying. I kept failing. Finally, I tried pink and it worked for this composition.

Fast forward a few weeks to getting the painting photographed for prints. We’re talking high-resolution photographs. The kind that would allow me to reproduce the art smaller and larger than the original 14×18 without losing clarity.

The photographer couldn’t get the proof prints right. No matter what he tried, the colors were off. When he explained that he was getting blotchy color in the background, my husband remembered my struggles painting that area. We told the photographer how many colors I’d used and he was able to filter for them. Problem solved!

The bottom line is that even though I wasn’t using the Flemish method—I painted all those paintings using a direct method—and the paint layers were opaque—or so I believed—the high intensity light necessary for photography was influenced by every color I put on that canvas!

That’s why it’s important to paint every layer in the Flemish method and to paint every one as though it was going to be the final layer.

It will make a difference.

How Do I Know When a Layer is Dry Enough to Paint Over?

Under ideal conditions, it takes about four weeks for each layer except the umber layer to dry all the way through. The umber layer generally takes a week or two.

If you begin painting too soon, you risk damaging the integrity of the previous layers of work and may cause the painting to fail long-term.

But you can’t tell whether previous work is ready to paint on by touch alone. Paint can feel dry to the touch, but still be curing beneath.

There are two ways to tell how dry a paint layer is.

The Cloth Test

Use a clean white cloth to lightly rub a portion of the painting very lightly. If the cloth picks up any color at all, the paint is not dry, even if it feels dry to the touch. Let the painting dry a day or two and test it again. When the cloth is clean after rubbing the painting, it’s time for the razor blade test.

The Razor Blade Test

Use a standard razor blade. You can round the corners to avoid gouging the painting if you wish, but it isn’t necessary.

Rest the blade against the painting and draw it lightly across a small portion of the surface. An inch or two is sufficient. Use light or very light pressure.

If a roll of paint forms along the blade, the paint is not dry all the way through. Let it dry a few more days or a week and test it again.

If you get powdery residue, the paint is dry all the way through and it’s ready for the next step.

Can I Just Start Painting The Next Layer?

Before you proceed to the next layer, it’s important to condition the painting surface. To condition the surface, pour a little linseed oil into the palm of your hand, then rub it over the surface of the painting with your bare hand. You don’t need to use very heavy pressure.

The warmth of your hand and the movement over the surface of the paint will warm the oil and “open the pores” of the paint film so that it will more readily accept new paint. This allows new layers to bond more easily and completely with previous work and will help insure the integrity of the overall painting.

Make sure the entire painting is oiled, then use paper towel to wipe off excess oil. If the surface of the painting is shiny, there’s too much oil and that will keep the new paint from properly sticking to the old paint. If the surface of the painting has a satiny look, it’s ready for paint.

Walnut oil is also acceptable. I use walnut oil because the paints I use—M. Graham Oils—are produced in a walnut oil vehicle.

What If It’s A Long Time Between Layers?

What if life gets in the way and you end up setting aside your painting for months or even years? Can you still finish it?


You’ll just need to do one extra thing in preparing the surface before you get back to work. Well, maybe two. If the painting happens to have gathered dust, dusting it will be the first thing to do!

The next thing to do is eliminate the glossy surface of curing paint so that previous paint films will accept new work. What do you need for this? An onion.

You read right.

Onions contain ether oil, which is capable of softening dried paint (among other things.) You can purchase onion oil or other types of oils for artistic use, but a half onion works just as well and is less expensive.

All you do is cut an onion in half and rub the painting with the onion. Make sure to cover every part of the painting because any part you miss will remain impermeable and new paint may flake off that area.

Then condition the painting as described above and you’re ready to paint.

Read more about reviving old paintings with an onion.


Those are the five questions I most needed answers to when I was learning the Flemish method. If you’ve wondered the same things, I hope I’ve provided the answers for you.

If not, let me know in the comment box below and I’ll do my best to answer them.

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