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If you have worked with watercolor paints, then you are very likely familiar with the frustration of paper that buckles and warps. When paper warps it causes paint to flow into the valleys from the ridges and can easily ruin a painting. All kinds of paper can warp when exposed to too much water. In fact, even watercolor paper is guilty of warping! If you know you will be using a lot of water in your painting then it is important to stretch your paper beforehand. Stretching your watercolor paper is the best way to prevent warping and keep your painting flat and intact. This article is all about how to prepare watercolor paper to prevent warping.
Table of Contents
- 1 Why Does Watercolor Paper Cockle and Warp?
- 2 What Does Stretching Watercolor Paper Do?
- 3 How to Stretch Watercolor Paper: Step-by-Step Instructions
- 4 Stretching Watercolor Paper: Tips and Tricks
- 5 Frequently Asked Questions
- 5.1 Can I Dry My Watercolor Paper Using a Hairdryer?
- 5.2 How to Stretch Watercolor Paper Using Masking Tape?
- 5.3 How to Clean the Wooden Board After Stretching Watercolor Paper?
- 5.4 How to Avoid Warping if I Don’t Want to Stretch Watercolor Paper?
- 5.5 What Wood Should I Use as a Watercolor Stretching Board?
- 5.6 What Is a Paper Stretcher?
- 5.7 What Are the Downsides of Using Staples to Stretch Watercolor Paper?
Why Does Watercolor Paper Cockle and Warp?
When watercolor paper becomes misshapen and deformed it is known as cockling, warping, or buckling. The reason watercolor paper cockles is because during the manufacturing process cotton fibers of the paper align in the same direction. When the paper comes into contact with water it will expand lengthwise and the fibers become aligned more randomly. As the paper begins to dry, some fibers will revert to their initial alignment while others will remain irregular. This process is what causes the ridges and valleys on the surface of the watercolor paper.
These ridges and valleys make it quite difficult to control the flow of your paint. It becomes a problem while trying to paint because the paint tends to flow towards and pool in the depressions. Warping is most common with papers that are 200lbs/425gsm or lighter since they can be prone to absorbing too much water when painted on. However, this will fluctuate based on the individual style of the artist, as some watercolor artists use less water than others.
What Does Stretching Watercolor Paper Do?
Stretching watercolor paper involves soaking the paper and placing it on a rigid surface while it dries. Once it dries while being attached to something stiff and rigid, it becomes taut and resistant to warping. This means that you can paint without the worry of struggles against puddles of color forming in the depressions of your paper. Many watercolor artists stretch their paper to avoid warping and once they have experienced working on taut, flat watercolor paper there is no going back to struggling with warping.
Commercial watercolor paper is usually mass-produced and during the manufacturing process, it is treated in a way that alters its absorbency and improves handling. The way manufacturers alter watercolor paper is by adding a chemical called “sizing”. Sizing is added to untreated watercolor paper because otherwise, the paper would have a very high rate of absorption. Untreated watercolor paper has a rate of absorption similar to that of blotting paper and would suck up all of your paint. In this way, the addition of sizing helps to make the paper less absorbent.
One problem with the addition of sizing is that it will sometimes be applied irregularly on the surface of the paper. This means that the absorption rate across a single piece of watercolor paper can vary. If there is a varying rate of absorption across a piece of paper, you may find that there will be blotches in some areas of your painting.
The process that is used to stretch watercolor paper also helps to redistribute some of the sizing. While this is an unintentional consequence of the stretching process, it helps to contribute towards a less problematic watercolor painting experience. Below we go into more detail about how to prepare watercolor paper in this way.
How to Stretch Watercolor Paper: Step-by-Step Instructions
If you are a watercolor artist that is looking to stretch some watercolor paper you may be worried that it is a difficult or time-consuming task. Stretching watercolor paper is actually a very simple process and can be easily streamlined to be less time-consuming. Below we go into detail about how to stretch watercolor paper and what you will need to do it using a board.
Things You’ll Need
- Watercolor paper
- A tub of water
- A rigid board of choice
- A sponge. Two sponges if you are using gummed tape.
- Gummed tape, or staples
- Staple Gun (if using staples)
- A staple remover (optional, if using staples)
- Craft knife
Soak and Prepare the Watercolor Paper
The first step when soaking watercolor paper is to fill a clean bath, basin, or plastic tub with about four to six inches of cold water. Make sure that your plastic tub is large enough to fit your watercolor paper into without having to bend it. Lay the paper on the surface of the water and then push it under.
Allow the watercolor paper somewhere between five and ten minutes to properly soak. Frequently check the watercolor paper to see if it has soaked enough. You can check watercolor paper in this way by slightly bending down one of the corners. If the corner remains folded when you release it then the watercolor paper has soaked enough. If the corner reverts back when released it needs to be soaked for more time. If the corner flops down onto itself then the watercolor paper has soaked for too long. You can still stretch paper that has absorbed too much water but it may absorb too much paint once you try to use it.
Once the watercolor has soaked enough, you can gently pull the paper out of the tub by tugging at two corners. You can give the paper a few small shakes to help it release some water and then hang it to rest on the side of the tub to drain off excess water.
Stretch the Watercolor Paper
To start stretching the paper you will need to fasten the soaked watercolor paper to your watercolor stretching board. Place the soaked paper onto the rigid support of your choosing. Since the paper is wet, you should try to place it in the correct position the first time around, as it will readily stick to the surface and can be tricky to move around. Be sure that you place the paper with the workable side facing upwards. Usually, you can tell which side is correct because there will be a watermark present.
Use a damp sponge to gently push out any air pockets or excess water and flatten the paper. This is also the time to gently stretch the paper outwards. You do not have to lift the paper upwards to stretch it outwards, just work from the center and focus on expanding the paper outwards.
Attaching With Gummed Tape
Gummed tape is activated by water and penetrates deep into the fibers of the paper to provide proper adhesion onto soaked watercolor sheets. Other tapes will not readily adhere to wet paper and will not properly hold the paper in its stretched position as it dries. Gummed tape may not be a suitable option for people who are using a large watercolor paper sheet or who have not soaked their paper for the correct amount of time.
Take a strip of gummed tape and activate the glue side by rubbing over it with a fresh damp sponge. Don’t wet or rub the tape too much as you could remove some of the glue. You should also be careful not to let any of the glue from the tape drip onto your watercolor paper.
Tape down the top and bottom of your paper with one long horizontal strip on each side. Place the tape so that it adheres to at least a quarter-inch wide area of your watercolor paper. Check for any air bubbles and remove any that have appeared by using a damp sponge. Be sure not to use the same sponge that you used on your gummed tape. Once you have taped the top and bottom of your watercolor paper, you can repeat the process on the left and right sides.
Attaching With Staples
If you don’t want to use gummed tape to attach your watercolor paper to the board, another option is to use staples. Some artists prefer to use staples when stretching watercolor because it is faster and can be less prone to adhesion failures like tape. Tape failure is most common when the paper has been soaked too much or too little, or when you are working with a large watercolor paper sheet. Staples are also a good choice if you have a board that is not much bigger than your sheet of paper and you do not have the room to use tape.
Begin stapling the paper to the board. Start in the center of each side and move towards the corners. Make sure that you are keeping the paper stretched and working out any air bubbles and excess moisture you encounter as you work.
Place staples around a half-inch in from the edges and around one and a half inches apart from one another. Staple around the entirety of your watercolor paper.
Drying the Stretched Watercolor Paper
Leave the watercolor paper out to dry completely for around 24 hours. This will be a bit annoying and time-consuming if you want to start your painting as soon as possible. You can avoid this by preparing multiple watercolor sheets at a time and storing them for later use.
Removing the Stretched Watercolor Paper
Once the watercolor paper has dried, you can paint straight onto it before allowing it to dry and then remove it, or you can remove it and then paint on it. The choice is up to you, the procedure will be the same either way. The only difference you will have in removing the stretched watercolor paper comes down to whether you used gummed tape or staples.
Removing Gummed Tape From Watercolor Paper
Pierce the tape where the paper meets the watercolor stretching board by using a safety knife. Slide the knife in this way around the edges of your watercolor paper. This will leave half of your tape on the board and the other half on your watercolor paper. You can now either cut off the tape as well or leave it to be hidden under a frame but you cannot fully remove it from the watercolor paper.
Using water to try to remove the gummed tape will still leave behind some sticky residue while trying to manually lift it will tear your paper. The tape on the edges of the paper adds some stability, and you can purchase white, acid-free gummed tape if the brown tape is unappealing to you.
Removing Staples From Watercolor Paper
If you used staples to attach the watercolor paper to your board then you can just use a staple remover to detach the paper once it has dried. A staple remover prevents you from hurting your hands unnecessarily and saves you a lot of time and trouble.
Once the watercolor paper is loose from the board you can cut around the edges to make a smooth edge and to remove the staple holes. Alternatively, you could leave the holes on the paper to be hidden under a frame at a later point.
Stretching Watercolor Paper: Tips and Tricks
Even though stretching watercolor paper is quite an easy process, there are some important things that you need to keep in mind. There are a few things that can determine how effectively you will stretch your paper or how pleasant your painting experience will be later on. These tips and tricks will help to ensure that you don’t make any mistakes while stretching your watercolor paper so that you can have the best stretched watercolor paper available for your artwork!
- Make sure that you do not soak the watercolor paper with too much water. If the watercolor paper has been over-soaked, the binder will wash away and leave the paper weak and vulnerable to damage or breakage.
- Make sure that you soak your watercolor paper long enough and use enough water when soaking. If you don’t soak the watercolor paper long enough or don’t use enough water then you will have the paper warp once you begin painting.
- If you are using tape while stretching your watercolor paper, don’t use masking tape or watercolor tape in place of the specified gumstrip tape/gummed paper tape. These tapes will not stick and don’t stretch along with the paper. Masking tape and watercolor tape are used for covering areas that you do not want to paint on.
- When wetting your gumstrip tape, make sure that you do not over-wet the tape. Gumstrip tape that is too wet will not adhere well enough to the watercolor paper and the paper will not stretch properly.
- Remember that you should only be wetting paper in cold water. Warm water will dissolve the sizing of your watercolor paper and make it prone to damage and degradation.
- When leaving your stretched watercolor paper out to dry you should never leave it to dry at any vertical angle. Only ever lie your water down to dry completely flat. This is because allowing your watercolor paper to dry vertically will result in the water running towards and pooling at the bottom of the paper. This will create less tension in your watercolor paper and prevent it from being properly and evenly stretched.
- Don’t try to speed up the process of drying your stretched watercolor paper by using a fan or hairdryer. These methods can cause uneven drying and varied tension across the surface of your paper. Watercolor paper that has varied tension has not been properly stretched and will warp when painted on.
- Wash your hands before handling your watercolor paper. You don’t want to get any dirt or oils on your fresh piece of paper before you even begin painting.
- Stretch multiple watercolor sheets at a time. This will help save you time in the long run so that you don’t have to wait overnight for your paper to stretch whenever you feel like painting.
- Always soak your watercolor paper for stretching by immersing it in water. Don’t use a spray bottle since you will quickly find that it isn’t capable of wetting paper enough for stretching.
- Use a board that is a minimum of 1 inch larger around all sides of your sheet of paper. This allows room for the tape to adhere to the board after you have stretched your paper.
- Use a canvas stretcher that is about 1 inch smaller than the paper you are using. This is because you will need to fold the paper over the edges of the canvas stretcher to staple it down tautly.
- Do not try to remove the gummed tape once your paper or painting has dried. The tape will damage the paper if removed while dry. If the tape is removed while wet it will still leave residue behind.
- You can find white acid-free gummed tape online if you do not like the standard brown gummed tape. This can be helpful for artists that don’t want to cut the tape off or who won’t be hiding the tape under a frame.
The practice of stretching watercolor paper before use is something that many artists can’t stop doing once they start. Using watercolor paints on a stable, smooth, flat medium is very important for achieving the painting you want. While it can be daunting to take on a new DIY art project, stretching watercolor paper at home is easy and cheap. It also helps you to become more familiar with your medium and why it works the way that it does. This sort of intimate knowledge and familiarity with your selected medium is what helps you become an experienced artist with high-quality pieces.
Frequently Asked Questions
Can I Dry My Watercolor Paper Using a Hairdryer?
You shouldn’t use a hairdryer to try to speed up the drying time of your watercolor paper because it can make areas of the paint dry at a different rate. This can cause the paper to warp and deform which would defeat the purpose of stretching it in the first place. You should instead leave your watercolor paper to air-dry in a warm, dry place for around 24 hours.
How to Stretch Watercolor Paper Using Masking Tape?
The short answer with regards to how to stretch watercolor paper with masking tape is that you shouldn’t. Masking tape isn’t suitable for withstanding the wetness of soaked watercolor paper and cannot adhere to the paper properly in order to aid it during the stretching process. Gummed tape is the product that should be used to stretch watercolor paper.
How to Clean the Wooden Board After Stretching Watercolor Paper?
Use a sponge to moisten the remaining gumstrip on your board for at least twenty minutes. It should lift quite easily with a palette knife or scraper. You can then rinse the board with water and a light soapy solution once more before drying and storing it for future use.
How to Avoid Warping if I Don’t Want to Stretch Watercolor Paper?
You could try using a watercolor board, a watercolor block, or a pack of pre-stretched watercolor paper. A watercolor board is made from a piece of watercolor paper that is attached to a thin piece of board. A watercolor block allows you to paint on the topmost layer and then peel it off with a palette knife once dried. Both these options are very convenient, but they are more costly than a pack of pre-stretched watercolor paper. Pre-stretched watercolor paper is also pricier than normal watercolor paper that you would have to invest time into stretching yourself.
What Wood Should I Use as a Watercolor Stretching Board?
Sealed plywood, glazed artist board, traditional wood drawing boards, or foam core boards are all great options to consider when choosing a watercolor stretching board. Regardless of what you choose, just make sure that you choose something that will not absorb water and swell or rot over time!
What Is a Paper Stretcher?
A paper stretcher uses clamps to hold the soaked watercolor paper to a board for stretching. They are available in different sizes at art stores and online. Paper stretchers can be very convenient for some artists but they take up about just as much space, take around the same amount of time to use, and are used in the same way. They are just convenient because you do not have to periodically repurchase gummed tape or staples to stretch your watercolor paper. This means that paper stretchers are a less costly investment in the long run.
What Are the Downsides of Using Staples to Stretch Watercolor Paper?
One of the downsides to using staples to attach your wet watercolor paper to a board is that it doesn’t hold as tautly as gumstrip. On the other hand, staples are more secure and are less likely to come loose than gumstrip. Staples can also be easily removed once you have dried the paper and you can cut along the edges to remove the holes.