Artist Ray Horner

Many beginning students wonder what drying time has to do with specific oil paints. Once they create their painting they notice that it may crack. The fact is that drying times can range from overnight to several days. The type of paint can not only affect the drying time but contribute to cracks in your oil painting creation.

How?

There is a basic principle in oil painting called FAT over LEAN paints. And how these paints socialize with each other can affect the drying time of your painting.

A FAT paint is introduced to the world directly out of the tube. Now if you mix this kind of paint with any kind of oil it only becomes FATTER. Not only will it take much longer to dry but it can fool you into thinking it is dry when you touch it. Yet, under the surface of the painting it is still trying to dry.

It is almost like having internal stitches after surgery and doing too much activity only to find out that the internal stitches have not fully healed. Hence, FAT paints can lull you into a false sense of security. Yet, if you have applied the FAT paint first it will still be drying under whatever paint is applied over it.

You are probably wondering “So what paints will make you think that the entire painting is dry?” I am glad you asked, the answer is LEAN Paints.

A LEAN paint is an oil paint that is mixed with more turpentine than oil. So, unlike FAT paints, it will dry faster! So, if the LEAN paint is applied OVER the FAT paint it is going to DRY FASTER.  And guess what? When the FAT paint underneath starts to dry it will cause the LEAN paint to stretch and crack. Ouch!

So what are some points to remember?

• The fact that lower layers wil soak up the oil from the layers above them. Therefore, every layer of paint you apply on an oil painting should be a little FATTER then the layer before it.
• Paints like prussian Blue, flake white,ultamarine and titanium white have a low oil content(Leaner) and will dry faster
• Paints like cadmium red and cadmium yellow have a medium oil content (FAT and LEAN) and will dry much longer like perhaps five(5) days.