Lesson 3: Using Multiple Overlay Stencils
Lining up your Overlays
The main reason to use an overlay is to eliminate the bridges and gaps that are almost inevitable in a single sheet stencil. They are also useful in helping you to separate colors. If two colors are very close together in a design it can be tricky to keep a brush loaded with the wrong color from hitting those adjacent areas. So a stencil designer may choose to both eliminate the bridges on the second overlay and to separate areas of different colors so that you can stencil without that danger. This does not mean that every overlay is its own color. You may have some leaves, a few flowers and some stem elements on more than one overlay – each requiring their own colors. But they will be separated from elements of a different color on that same overlay.
Another reason to use overlays is that you can then add in small details that simply cannot be cut into a single sheet. If you tried to cut the veins of a leaf into a single sheet stencil the entire center might fall out. But you can cut those into an overlay and then stencil the veining on top of the plain leaf you just stenciled.
Sometimes – but not often - the overlays are there to help you create the effect of shading and highlighting.
When I did my first multiple overlay stencil I mistakenly believed that the extra overlays were there to help me produce the lovely shaded effects that I saw on the illustration of the finished product. So I dutifully would stencil all the leaves from overlay one in a dark color, all the ones on the second overlay in a lighter shade, etc. I could not understand why mine didn't look like the picture.
What I soon realized is that while some parts of some overlays were there for that reason – for instance a curled leaf would have a lighter underside than the main portion of that leaf – most of the time the leaves were on a different overlay for structural reasons – to fill in bridges that were needed on the first overlay. How can you tell which is which? This is why you should do a "proof" of your stencil when you first use it – so that you know what the parts of each overlay are actually intended to be. It can be hard to tell by simply looking at the Mylar sheets separately. Sometimes the cut out portions there don't resemble anything at all. If they are mere bridges then they won't be representations of anything familiar and you won't know how they fit into the bigger picture until you actually apply paint to them and see what their function is.
When you use a multiple overlay stencil, the major difference is that you now have to make sure that your second (and third, fourth, etc.) stencil overlay line up exactly with the first one. Otherwise, you'll end up with bridges anyway – or a tree trunk that isn't quite under the branches, a bird whose beak doesn't quite meet its face, etc.
Registration marks Most modern stencils come with registration marks. In the single overlay stencil these were useful only to make sure that when repeating that stencil in a border, your repeats met properly and stayed straight. So chances are you only used the marks at the end of the stencil, where it joined to the next one.
Now you are laying one stencil over another, so you will find that you need at least two registration holes to mark – one on the right and one on the left, usually at the top. For added safety, many have registration marks in all four corners. Make it a practice to mark the registration holes for your first overlay even before you begin to paint. If you don't, it's too easy to forget until after you have removed that overlay and are trying to position the next one. It may seem simple to line things up, since your stencil is clear – but it now has paint all over it and isn't quite as easy without those holes to guide you. But if you find the marks that you made when beginning to stencil, and make sure that they show through all the registration holes on the second stencil, you are guaranteed that everything will fit together.
Outline Registration A few stencils that I have worked with have an outline of the finished stencil on each overlay. That way you can tell where you need to be by lining those outlines up with whatever has already been stenciled. To keep it simple, day you have a two overlay stencil – leaf and veining. The stencil with the veining will also have an outline of the leaf printed on it. Place the outline over the already stenciled leaf and your veins will be in the correct place.
If your stencil doesn't come with these outlines, you may want to add them for yourself. They really are extra insurance that things will come out as professionally as possible. Simply get a permanent felt tip marker and trace the outlines of each element onto the other, using the cutouts as your guide. Do this on what you consider to be the top of the overlay rather than the underside, as there is a slight chance that the felt tip marking may transfer itself to your stenciled surface.
Tracing Paper Overlays If you are working with an opaque stencil, then none of the methods of alignment will quite work. Instead, you want to get a sheet of tracing paper. Layer your stencils so that they form the complete picture and then trace the resulting outline. This will give you a good idea of the overall finished stencil placement. Now make sure that you also trace the position of each separate overlay as they fit together. When positioning the actual stencils for painting, use this tracing paper template to check to see that your overlay is in the right position.
