Lesson 3: Stenciling with Plaster
Basics for Indoor Plaster Stenciling
For indoor projects, the basic stencil supplies that I indicated, used along with a bucket of inexpensive joint compound, will create a beautiful white raised design in your walls which can then be painted the same color as the wall for a subtle effect, or left white on a colored background, which creates an appearance similar to Wedgwood Jasperware. Joint compound has about the consistency of cake icing, and goes on nearly as easily.
The other supplies you need for indoor plaster stencils are colorants. The type you choose will depend on the effect and depth of color that you want.
You can also rub stencil crèmes over the raised design should you prefer a pastel tint, or with metallic paint for a richer look, as I did on my kitchen drawer fronts here. Don't try to brush it on - scrub the color in with an old soft towel. You have a better chance of getting some of your color onto the edges without tinting the wall behind it with the scrub method than you will with a brush.
You can also glaze the entire wall, which will leave your plaster design paler and more prominent than that of the glazed-over the background (unless it is also white). A metallic glaze can be rubbed over the raised areas of a stencil painted the same color as the background for a rich, highlighted effect. Or, as in this instance, I triple glazed the strip that the plaster is on, leaving the surrounding areas only lightly gilded.
HINT: If your glaze is too deep and the project doesn't stand out the way you hoped, take a soft cloth and rub the glaze off of the most prominent areas of the design, allowing the base plaster to show through. Just rub lightly. You don't want to take off too much, but you do want to create a difference between wall and stencil. This must be done quickly while the glaze is still wet, so for large portions you may want to glaze only small parts at a time.
Should you prefer to work with more definite color, you have a few options. The joint compound can be tinted with regular acrylic stencil paints. Because the plaster is so very white, this will leave you with a pastel color no matter how deep a color your paint is. Too much paint will make the plaster too thin to be workable, especially on a vertical surface. This can be a tricky option, since you can't really predict exactly how deep the color you will end up with when the plaster starts to seem too liquid may be.
Another option is to take your joint compound to the paint store and have them tint it with universal colorants - the stuff used to color paint. These colorants are very concentrated, and so you will be able to get more depth of color from them than the acrylics before the mix becomes too liquid. Just have them remove the lid to let you peek to make sure that a) you like the depth of color and b)your plaster is still thick enough.
Amazingly enough, the deepest colors available will come in the bakery section of a food or crafts store - the icing coloring pastes used to tint cake and cookie frosting. These colors are unbelievably concentrated, so that even the whitest of icing can be turned to coal black when a bit of this is mixed in. You will undoubtedly need more for a large plaster stencil project - but it's the best way to get a deep color for your finished product. If that intimidates you a bit, then scour the shelves of the crafts store until you find paints labeled "pigment."
WARNING: If tinting plaster with any of the above keep very careful account of the proportion of tinting medium to plaster, so that, should you run out, you can recreate the color in your second batch.
If your plaster design is in an area that will receives a lot of traffic you may also want to protect it with a clear sealer of some kind - especially if you choose to leave it in its original white color.
Clean-Up
Cleaning up after yourself - and cleaning up any small errors on your project, is simple.
If you find that your edges aren't as sharp as you like, if the plaster is still damp you can remove the smeared part with the blade of a craft knife or a Q-tip - or even your finger. You can also sand lightly to remove any rough edges once things are dry.
Cloudy pieces of bacground where the plaster accidentally smeared a bit clean up with a damp cloth or paper towel - and I've been able to do this even a day after stenciling.
Your trowel will clean up easily in water, as will your stencil. Remember that many trowels rust, so be sure and dry them carefully.
But unless your project is quite small, you may want to think twice about washing all that plaster into your sink. It can harden and clog the drain. A good option is to hose the stencil off outdoors, If it's winter, try using a dishpan or old clean cat litter pan, reusing the water until it gets too cloudy and then tossing it outdoors. Just be careful not to toss it in a spot that someone may walk on.
