How to keep watercolor flat? You might notice that after you paint, the paper warps or buckles. This is because watercolor paper expands when it’s wet. In this blog post, I will share with you 5 easy methods to stretch watercolor paper so it will stay flat while and after you paint.
Stretching watercolor paper is a necessary step in preparation. When the paper absorbs water, it expands and causes cockling – the situation when the paper sheet is wrinkling and ridging. When you paint colors on unflattened paper, the pigments will gather in paper valleys, resulting in an unsmooth wash and unexpected effects.
Warped watercolor paper will not only affect the quality of the final painting but also its presentation. No matter how hard you try to flatten it, it will never be as flat as before painting.
Do You Need to Stretch 300 gsm Watercolor Paper?
Yes, you still need to do it even if it seems thick. Stretching watercolor paper before painting will allow you to paint in many layers with a lot of water.
How Do You Stretch Watercolor Paper Perfectly?
Different artists have different ways of stretching watercolor paper. The basic methodology of stretching watercolor paper comprises two steps: first you soak the paper in water, then you fix it to a painting board or a hard surface. The paper expands when it is wet. When it dries, the paper will be stretched as a drum and will not create wrinkles.
How Long to Soak Watercolor Paper to Stretch It?
5 to 10 minutes should be enough to soak watercolor paper. There are different ways to soak the paper with clean water.
- Use a big brush to paint water on one or two sides of the paper
- Use a sponge to wet the paper. Be careful to avoid damaging the paper surface.
- Immerse the whole paper sheet in a water tub or basin.
- Let water from the tap run on the paper on both sides.
After the paper is soaked with water, let it rest on a flat surface for about 2 minutes before stretching it.
Read on for 5 ways to stretch watercolor paper, from the simple to the more complicated ones.
Stretching Watercolor Paper with Masking Tape
I have seen many people use masking tape to fix the paper on a board, and then paint on it. This way is simple as you can quickly do it in less than 2 minutes. However, it doesn’t protect your paper from buckling. As soon as you paint with water, the paper surface will deform.
To avoid this, you need to make the whole paper sheet wet so all fibers in the paper can expand. There are two ways to stretch watercolor paper with masking tape.
The first way is to fix the dry paper on a board with masking tape at the four edges. Then, use a big brush such as a flat brush to “paint” clean water on the whole top surface of the paper. After that, you can start painting.
The second way is to wet both sides of the paper first. Next, when the paper is almost dry, use masking tape to fix the paper on a board.
Stretching watercolor paper with masking tape is easy, but it isn’t perfect. Masking tape doesn’t expand with the paper and cannot stick well on wet paper. Some colors will bleed into the white edges where you want to reserve with the masking tape. To avoid this, we can replace the masking tape with gummed tape as described in the next section.
Stretching Watercolor Paper with Gummed Tape
Gummed tape is the tape that is activated with water. You can use a brush or a sponge to wet the glue side of the tape with water. Try not to rub it too hard or too wet, otherwise, the glue might be gone.
Gummed tape expands when it’s wet while masking tape doesn’t. This is why gummed tape is better for stretching watercolor paper.
- To stretch watercolor paper with gummed tape, you need to soak the paper in water first.
- Then, activate the gummed tape with water and fix the edges of the wet paper on a waterproof board.
- Remove all air bubbles under the paper
- Finally, put the board flat and let the paper dry before painting. If you keep it vertically, the water will run to the bottom and the tape will not stick.
The board needs to be hard and thick enough, otherwise, the paper might bend the board when it dries. You can reinforce the fixing with staples.
After painting, you can use a paper cutter to cut along the edges to remove the tape. Don’t try to peel off the tape because it might rip off your painting.
Watch the tutorial below by Blick Art Materials for demonstration:
How to Stretch Watercolor Paper with School Glue
Gummed tape isn’t always available, so how to stretch watercolor paper without tape? Luckily, you can use school glue. I usually use this method to prepare my paper before I paint. It is cost-effective and convenient because I can find school glue in almost all stationery. For a nomadic artist like me, school glue is the perfect option.
So, how can you stretch watercolor paper with school glue?
Step 1: Soak watercolor paper in water or rinse it under running water
Step 2: After soaking the paper and letting it rest, spread school glue on one paper surface that is not used to paint. Make sure to cover all edges of the paper with the glue.
Step 3: Flip the paper and stick it on a painting board. Remove all air bubbles.
Step 4: Let the paper dry before painting. Keep the painting board laying flat.
You might wonder if it’s easy to detach the painting from the board after painting. The answer is yes, it’s easy to do it, as long as you use a waterproof board.
Stretching Watercolor Paper with Staples and Frames
Many artists like this way of stretching watercolor paper. The paper when dry will be flat and tight as the drum. To do this method, you will need a wooden frame, a stapler, and watercolor paper. You can use a framed canvas or make a custom frame for this purpose.
Here are steps to stretch watercolor paper using staples and a frame.
- Soak watercolor paper in clean water for about 5 minutes
- Let the paper rest for about 2 minutes so the water can drip off the paper
- Put the paper flat on a waterproof surface. Remove air bubbles underneath the paper
- Put a frame on the paper
- Fold the edges of the paper to wrap the frame and use the stapler to fix the paper to the frame
- Leave the frame and the paper flat to dry before painting
To remove the painting from the frame, use a cutter or scissors. Remove the staples from the frame so you can reuse the frame next time.
The short video below shows you how to stretch watercolor paper with this method.
How to Stretch Watercolor Paper with a Watercolor Paper Stretcher
You can buy a watercolor paper stretcher to stretch paper. These stretchers are designed to stretch the paper similarly to using a frame and staples but are easier to use. Watch the video below for how the artist uses a watercolor paper stretcher to stretch the paper.
Alternatives to Stretching Watercolor Paper
If stretching paper sounds too complicated and time-consuming, you can consider the following alternative solutions.
Watercolor Blocks - Pre-stretched Watercolor Paper
Watercolor blocks are blocks of watercolor paper pads that have four edges glued together. You can paint directly on a paper pad without stretching it. The glued edges keep the paper fixed to the block and prevent it from warping or cockling.
When the painting is done and dry, use a flat and thin paper cutter to carefully detach the pad from the paper block.
Watercolor blocks work fine when you don’t use too much water for your painting. When too much water is used, the paper sometimes still deforms and creates valleys.
Thick Watercolor Paper (Cardboards)
Thick watercolor cardboard is pre-mounted and thicker than regular watercolor paper pads. You can paint on watercolor cardboard without stretching it beforehand.
The Takeaway
Preparing paper before painting is necessary as it keeps the paper flat the whole time you paint, avoids unexpected painting effects, and makes the presentation of the final painting look better. Learn and try the five ways to stretch watercolor paper to see which works best for you.
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