In woodworking, there are many ways to alter the appearance of wood. Often, it is desirable to change the color of wood. Three main options are painting, staining, and dying. Painting, of course, completely obscures the surface of any wood. But if you want the grain of the wood to be visible in your project, you should either choose to stain or dye. Stain and dye are not the same thing!
What is dye
Dye is typically made of very small molecules that have a specific natural color. Dyes are usually made available in the form of a powder which can be dissolved in either water, alcohol, or oil. Always be sure to read the label of your dye to see what it is soluble in. Also keep in mind that powdered dye is often a different color when it is dissolved in a solvent, so always judge a dye by the label, and not how it appears in a powered form.
Because dye is made of small molecules and particles, it soaks evenly into your wood. Dye does not stay on the surface of materials, but rather, it can soak into your wood a small distance. Dye is great if you want the grain of the wood to be visible, but not emphasized. One property of dyes to be aware of is that some are not color fast, meaning that if they are left in the sunlight for extended periods of time, eventually the color will start to fade. This is especially true of oil-based dyes, but can also be true about alcohol and water based aniline dyes as well.
What is stain
Stain is made of much larger particles called pigments. These pigments are what gives stains it’s color in a similar way to how pigments can give paint it’s color. Because of the size of pigments, stains do not soak into wood or any other material like dye does. Instead, pigments can easily settle within the grain and gaps in your wood. So if you’re working with a particularly porous wood, stain will dramatically emphasize the grain in the wood. In other words, stain does not soak evenly because it settles much more readily and deeply when a porous material allows it in some areas, and less in more smooth areas. One thing to note about stains is that if you want the grain of the wood to be visible when the project is complete, you can not apply many layers. If you do, one layer will just settle on top of the previous layer, and you’ll effectively be painting the wood with very thin coats of paint. Dye, on the other hand, can be applied in as many layers as you want until you achieve the color you were going for.
Which one to use
When making the decision to use dye or stain, it’s important to think about how you want your project to look when you’re finished. Do you want the grains to really pop out at the viewer? If so, maybe stains are the right choice. Conversely, if you want a nice even color in your projects, perhaps dye is the right choice. You should also consider whether your piece will be in direct sunlight for long periods of time. Those are the main things you want to think about when making your decision.