Watercolor on cardstock seems like a great idea for creating unique and intriguing card designs, but can it be done without damaging the cardstock?
Watercolor can be used on cardstock, but only sparingly and carefully. Further, you should select a thicker cardstock paper that weighs approximately 220gsm. This will ensure that the paper remains durable while painting. Tape down the cardstock while painting, in order to prevent it from curling.
Cardstock is a tricky surface for watercolor. The paint doesn’t dry as quickly on it as it does on paper. It is easy for paint to smear fast, and a single mistake can ruin a painting.
Painting quickly is the obvious solution, but getting the speed just right is difficult. You can’t really paint quickly and carefully at the same time.
Let me show you how to do it correctly.
How should you use watercolor on cardstock?
When painting with watercolor on cardstock, you have to be extremely careful not to damage it. Cardstock has a hard time absorbing large amounts of water, which causes it to flake up easily.
My advice on this issue would be to use very little water when painting.
Using two different brushes during the painting process would be a trick to achieve this. One of them is used to mix different colors, while the other one is used for painting only.
This will ensure that you only apply the paint and water you actually need to the paper and avoid flooding it with paint.
In addition, you should only use very light brushstrokes to avoid damaging the paper. You might tear the paper over time if you work quickly and aggressively.
This is particularly true with cardstock, so you should be aware of it.
Aside from those two factors, you can paint on cardstock just the same way you do on watercolor paper.
Cardstock can also handle a few layers of paint, but I think you’ll know when it’s too much.
If you’d also like to know how many layers watercolor paper can handle, check this article out.
How to prevent cardstock from curling during and after painting
How to prevent cardstock from curling while painting
Limit your paint and water usage
Water should be used very sparingly, as I mentioned before. The main cause of paper buckling or curling when being painted is too much water.
You can also take small breaks between painting layers to allow the paint to dry. Rather than letting the paint dry all at once, it dries gradually.
Related to this I would advise reading Does watercolor paint dry quickly?
Over time, the fibres of the papers adjust to the amount of water and prevent curling.
Wet the cardstock on both sides
The third method for preventing cardstock from curling is rather unconventional.
Basically, you wet both sides of your cardstock before painting, by applying a light layer of water to the backside of the paper before you start painting.
What is the reason behind that? Using a water-based medium like watercolor on just one side of the paper will only stretch and therefore weaken the fibres on that side, resulting in curling.
The fibres’ strength of the front and back of the paper don’t match, and this will result in curling.
When you apply water to both sides of the paper, the fibre structure will be similar, reducing curling.
Stretch the cardstock as you paint it
It’s probably the easiest and best way to prevent cardstock from curling.
When painting with watercolors, stretching the paper is fairly common, as it evens out the different fibres without the artist having to worry about it too much.
Whenever I stretch paper, I prefer to use masking tape because it is cheap, easy to apply, and doesn’t harm the paper.
Additionally, you can easily change the angle from which you paint while you are working on your painting.
Clamps are another option. To be honest, I find them a bit over the top and rather limiting.
Firstly, you do not always have a flat surface to clamp cardstock on. In addition, too powerful clamps can damage it.
In order to avoid this problem, I recommend placing small pieces of paper between the cardstock and the clamp as this will soften the direct force on the cardstock.
If not, the clamp might leave marks.
Thirdly, setting up and changing the position of your painting is quite tedious.
That’s just my opinion on the whole thing. By all means, if clamps are more useful for your painting process, please share your methods in the comments below or send me an email.
By the way: Clamps are often used for acrylic and oil painting as those mediums are primarily painted on easels. Read this to find out if an easel also makes sense for watercolor painting.
The best ways to flatten curled up cardstock
There is no solution that will completely fix the problem, it will still exist, just in a weakened form.
If you end up with curled cardstock, don’t worry because there are ways to flatten it again.
Flattening the cardstock by stretching it
After the cardstock is finished being painted, it can be stretched using the same methods I mentioned earlier.
The first method would be to use tape. As you would need pretty strong tape to stretch cardstock back into place, tape might be the less efficient option in this case.
Masking tape, which you would use to create sharp edges while painting, may not be sufficient to flatten cardstock adequately.
Clamps can be very useful in this situation. The negative attributes of clamps I mentioned earlier don’t matter as much anymore.
Since you don’t have to handle the cardstock anymore, you can clamp it pretty much anywhere.
But again, in order to avoid damaging the cardstock, you should place a piece of paper between the clamp and the paper.
Also, you should use clamps with a low amount of force since you don’t need to press the paper, but rather stretch it.
How to press cardstock back into shape
The other method to get your painting back into shape would be to press it.
Watercolor paintings have a tendency to curl a bit, so I’m sure pretty much every artist has done it at least once.
The process is pretty straightforward and hands-on. First, you’ll need to find a flat surface to press the painting onto. It can be a desk, a piece of wood, or even the floor.
In order to protect the painting from harm, dirt or damage, you’ll need two sheets of printer paper.
There is one sheet under the painting and one over it. Now you need to find a heavy item that can evenly distribute its force.
Additionally, it must be as big or bigger than your painting in order to fully press it and not leave marks behind.
A large book will do; a rock with sharp edges won’t.
This object needs to be placed on top of the sheet of paper that’s over the painting. After a couple of days, the painting should be flat again, given that the object was heavy enough.
If laminating a watercolor painting ever occurred to you, you should read this first.
How to control watercolors on cardstock
Cardstock sometimes has a very persistent surface, so you might have trouble containing the paint.
This will result in unwanted shapes and even watercolor seeping over the edges of the cardstock.
However, there are ways to avoid this.
Again, you should only use a very limited amount of water. This may prevent the problem in its entirety.
Another option would be to tape off the edges with masking tape. You can use this to create very sharp lines and prevent your water from flowing where you don’t want it to.
Make sure your tape won’t damage your painting by testing it on an additional sheet of paper first.
Painting with watercolor on cardstock requires you to avoid using too much water since most types of cardstock cannot absorb a lot of water. Tape down the cardstock while and after painting, in order to flatten it and create sharp edges.