London artist and art instructor Cheryl O gives the
following advice about pre-stretching your watercolour paper:
PURPOSE
When watercolor paper gets wet, it buckles in unpredictable ways. This "hills
and valleys" effect is much more difficult to paint on than a flat paper.
Pre-stretching the paper will greatly reduce this effect.
SUPPLIES
1. A board of soft wood such as pine, cut to just slightly larger than the
watercolor paper you like to work on. For example, many artists like working on
a quarter size sheet. This measures 11 x 15 inches, so a board approximately 12
x 16 inches or larger would suit this size of paper.
2. A spray can of Varathane non-yellowing varnish to coat the board with. This
is to protect your watercolor paper from the oils in the wood. In turns, spray
both sides of your board and let it dry well. Alternatively you could coat the
board with white or off-white latex paint if you have some around.
3. Watercolor paper cut to the size you prefer to paint on.
4. A clean sponge or cloth and a stapler.
PROCEDURE
1. Put a few inches of cool to lukewarm (not hot) water into a clean sink or
bathtub and lay your cut watercolor sheets into this. You can do several sheets
at a time, as long as you have a board for each. If you are using Bockingford
paper, set a timer for 14 minutes to let the paper soak well. If you are using
Arches, it takes only about 5 minutes to be saturated. If you see gray spots
suddenly appearing in your paper, take it out immediately - too much of the
sizing has dissolved out in those places.
2. Remove the paper and gently smooth it on top of a prepared board with a clean
sponge or cloth.
3. Starting in the middle of any side, staple the four edges of the paper to the
board. Place the staples about 1 inch apart.
4. Let the paper dry. This can take an hour or more depending on the weight of
paper and humidity. (I prefer to do this chore the night before and let it dry
overnight.)
5. The paper is now "pre-stretched" and ready for you to paint on. Do not take
the paper off the board, or take the staples out, until you are finished the
painting and it is dry.
Although it is called "pre-stretching" this process would be better named
"shrinking". Good quality watercolor paper is 100% cotton, and by wetting it and
stapling it, you are causing it to shrink tight like a drum cover on the board.
The next time you wet it (when painting), it will not stretch out as much.
FREQUENTLY ASKED QUESTIONS
Q. This seems like a bother, are there any other ways of managing the paper?
A. Some artists use bulldog clips to hold the watercolor paper onto the board.
As the wet paper stretches, they just open a clip and pull it tight again.
You may hear of artists using gummed packing tape instead of staples. I find the
tape rather messy when removing, and you lose more of the edge of the paper in
order to have it stick adequately. Lastly, if you work very wet, the tape will
lift and the paper buckle again.
Q. What about buying the watercolor pads that are sealed on the edges?
A. These pads are great for taking traveling or painting outdoors. Because you
leave the paper attached by the edges until you are finished each painting, it
doesn't buckle as much. However, the paper has not been pre-stretched and if you
work quite wet, it will still make those unwanted hills and valleys. I have
heard of artists wetting the top sheet of the pad with a sponge, and letting it
dry before working on it. That should help.
The major disadvantage of the sealed watercolor pads is their cost. It is a lot
cheaper to buy the paper by the sheet and prepare it yourself.
Q. Should I buy a staple gun for pre-stretching paper?
A. Large staple guns are not recommended simply because it is so difficult to
get the staples out of the wood when you are finished the painting. Smaller
hobby staple guns may work, however, this is not necessary. A good quality
stapler should staple into a pine board. You will find that it works more easily
to bite the wood with the stapler rather than opening the stapler up.
Q. What about a staple remover?
A. It is better to use a butter knife to slip under the staples. You can slip it
under both paper and staple if that is easier. The claw shaped staple remover
can damage the top of the paper.