Everything you can use for masking with watercolor painting is explained here – best masking fluids, easy ways to mask with tape, how to mask large areas without damaging your paper AND alternatives to masking – lifting out instead of using mask.
What Is Watercolor Masking?
Masking is covering part of your watercolor paper so the paint doesn’t get on it. Most commonly used is liquid masking medium and masking tape, but if you don’t have masking there are alternatives.
Masking Tape for STRAIGHT LINES
Masking Tape Tears My Watercolor Paper!
If your paper tears, you can try sticking the tape to your leg several times before applying it to take off some of the adhesive.
Or buy a better grade of paper or a different type of masking tape. Inexpensive brown colored masking tape that you can partially see through usually works well.
How to use Masking Tape for Watercolor
Place masking tape over dry paper that has not been wet before and rub the edges to firmly fix it to your paper. You can then paint over the area and the part under the masking tape will remain white.
If your paper has ever been wet at all, don’t use masking tape. The paint will creep under the masking tape and not leave a messy, jagged edge.
Masking tape is especially convenient for objects with straight lines like horizon lines or buildings.
How To Mask Angled Building Edges Easily for Watercolor Painting
Step 1 – Tear a piece of tape longer than you need and stick it firmly to your paper.
(This masking technique is shown in the watercolor Covered Bridge Lesson, as well as others.)
You need enough extra tape on the sides that you’ll be able to grasp it and tear off the extra in Step 2.
Step 2 – Hold a razor across the line, not pressing into your paper or you’ll scratch it. Just hold firmly.
Hold the razor along the line of the barn where you want to tear the tape. The razor acts like the sharp blade on a box of plastic wrap.
Tear the excess tape off and rub the edge to seal.
This is a quick and easy way to mask buildings.
If you use more than one piece of tape to mask an area, be careful when overlapping the pieces, as paint can creep in there, also.
Liquid Masking – Friend or Foe?
What is liquid masking and why should you use it?
Liquid masking is a fluid that you paint on an area and it keeps paint from touching that area. A common reason to use masking is to ‘save the whites.’ It can be difficult or impossible to paint nice washes of watercolor around small or picky areas, so, painting it first with liquid masking eliminates that problem.
Liquid Masking Versus Masking Tape
While masking tape works great on objects with straight lines, liquid masking works well on objects that don’t have straight lines – like these furry edges and whiskers, as well as other organic shapes.
(Note in the photo on the right, only the edges are painted and not the entire cat. You’ll find the draw backs to using masking farther down.)
Best Type of Masking for Watercolor Painting
I prefer Pebeo Drawing Gum (affiliate link) liquid masking over all the other types, although all work well. I do advise against buying white masking fluid, as it’s very difficult to see on white paper.
Pebeo is the only masking fluid that thins with water. When applied thickly, it dries fast and peels off easily, sometimes in one big piece (which is kind of fun.)
Liquid masking also comes in masking pens (affiliate link), which are convenient for small areas or thin lines like writing.
In the photo above, I wrote my name with the masking pen, dried, painted the water, then removed the masking so my name is white.
Fine Line Masking Applicators
There are several fine line masking applicators for sale. I’ve tried many, and they tend to clog up very easily. You may love them, but for me, they’re too expensive and not worth the hassle. See how to apply fine lines below.
How To Apply Liquid Masking for Watercolor
Paint liquid masking on the same way you apply watercolor paint, and just as carefully.
WARNING! Masking will ruin your brushes. Even if you rub a damp brush on a bar of soap before you dip in masking and paint it on, it is still hard on your brush.
Use an old brush, an inexpensive craft brush, or a silicone brush for masking. Dip your brush in the masking liquid and paint it on where you want it. Paint masking just as carefully as you would apply real paint.
To Apply Thin Lines With Liquid Masking – use a toothpick or stylet. Dip the toothpick in the masking and draw the line on until you run out of liquid. Be careful not to scratch your paper – keep a light touch.
How to Use a Masking pen – masking pens have a nib that fills with masking when you press down on a piece of scrap paper and hold it down. Once the masking has filled the nib, use it like an ordinary pen.
How to Remove Liquid Masking from Watercolor Paper
To remove liquid masking from watercolor paper, gently rub it off with your finger or a masking pick-up (also called a rubber cement pick-up or remover). Be careful not to tear the paper or rub so hard that you form a blister on your finger.
Masking Fluid Mistakes You Can Avoid
Masking Fluid Dries Out Quickly
Most types of liquid masking gunk up around the lid, keeping the lid from sealing the bottle. If your lid doesn’t seal, the masking will quickly dry out, turning in a large, unusable lump. To avoid this, store your masking upside down and keep the rim of the lid clean.
Masking Fluid Lifts Your Pencil Lines and Color
Don’t apply masking over pencil or traced lines that you want to keep. When you remove the masking, your drawing will be gone.
(That’s one reason why most artists only use liquid masking around the edges of areas they want to mask.)
Masking lifts color, also. If the area you’re masking has already been painted, the masking may lift some of the color. It depends on the type of masking you are using and your paper, so test it on scrap paper before you use it on a serious painting.
Masking Fluid Left On Too Long – Difficult to Remove
If you leave your masking fluid on for a long period of time, it may not come off… ever! Plan to finish paintings with masking fluid in a timely manner.
Masking Fluid Leaves Hard Edges
Masking fluid will leave crisp, hard edges on the area it masked out. This can be bad or good.
For far away objects, soft edges would be a better fit. Instead of masking, lift those out with Mr. Clean’s Magic Eraser and a stencil. (See demo at bottom of this post.)
For close-up objects, those crisp edges work well, popping the object out of the background.
Masking Large Areas for Watercolor Painting
Masking large areas, whether painted or not, is hard on your paper, hard on your brushes and hard on your wallet!
If you have a large area to mask, it can be easier to use plastic wrap to cover most of the area and seal the plastic wrap to the paper just around the edges with liquid masking. Practice this on scrap paper before you try it on a serious painting.
I use Press and Seal (affiliate link) for this. It is a somewhat sticky plastic wrap that can be found in your grocery store.
Tear off a piece of Press and Seal larger than you need for masking and lay it over the area you plan to mask out.
Use a sharpie marker or pen to lightly draw around the are you plan to mask. (Be sure the marker doesn’t go through the plastic and onto your painting.)
I know this stuff crinkles up easily, but try to slide a piece of cardboard between the plastic wrap and painting.
Then use a utility knife or exacto knife to cut the plastic wrap piece to just a little smaller than the desired area.
Slide the cardboard out. Press the plastic where you want it. Paint a thick layer of masking around the edge of your area to be masked and over the edge of the plastic wrap.
The liquid masking will hold the plastic wrap in place and seal the edges, so you have a large area masked out safely with only a small bit of liquid masking around the edges!
Alternatives to Masking – Lifting with Stencils
There are two alternatives to masking – painting carefully around an object (this can be difficult) and using Mr. Clean’s Magic Eraser (often with a stencil) for lifting up paint. Here’s a demonstration below.
First I painted the sky in this landscape with a big wash and big wash brush.
Second, I traced my swans onto the back of an old photograph and cut out a stencil, using an exacto knife.
Third, I taped the stencil where I wanted the geese so it wouldn’t slip, and used Mr. Clean’s Magic Eraser to lift off the paint. It’s very gentle and leaves the surface of Arches paper nearly perfect.
Last, I painted the swans.
These swans have soft edges from lifting, which looks right.
Plus, there’s no way to create a beautiful, loose wash of color when you’re trying to paint around something.