Stretching watercolor paper keeps it from buckling while you are painting on it. It is not necessary for 300-pound paper, but lighter papers will buckle when they get wet. 300 pound paper gets expensive, so many watercolor artists buy 140- pound paper and stretch it to a hard surface.
There are lots of ways to do this. Today I'm going to share with you how I do it. I drew some little doodles in my notebook to help you see what I mean.
You need a hard backing surface to stretch the paper to. I use gatorboard (aka. gatorfoam board). Gatorboard is similar to a super-thick piece of foam board, but it has a much stronger outer surface that will hold up a lot longer than foam board. It's lightweight, easy to staple (and remove staples from), and doesn't mind getting soaked, so it's perfect for this purpose. (You can find it at various art supply stores under different names, or you can order gatorboard from Cheap Joes Art Stuff, at http://www.cheapjoes.com- my favorite place!)
Other supplies: water, stapler and staples, masking tape or artist's tape, watercolor paper
Steps:
1. First I cut my paper to the size I need, and lay my gatorboard flat on a table or counter.
2. Next I hold the paper under cool, running water in the sink or bathtub, moving it around until it's thoroughly wet everywhere on both sides. I really let it run over it for a couple of minutes on both sides, so it gets nice and soaked. (Some artists choose to actually soak their paper in a tub of water.) After I've done this on both sides of the paper, I hold it up by one corner and let the water run off until it stops running and starts dripping. Then I hold the opposite corner up for a few seconds, so the excess water settles back onto the paper more evenly (vs. being pooled in one corner).

3. Then I lay the paper flat on top of the gatorboard and start to watch what happens. (Note- loose sheets of watercolor paper should be the same on both sides. Paper removed from a block or pad may have a front and back side.) As it buckles (ie. creates big wrinkles or waves), I tug gently on the sides to flatten it back out. If some areas (like corners) are drying to the point where they lose their sheen while other places are still very wet, I'll mist them with a spritz bottle to make them shiny again. Once most or all of the paper has absorbed the excess water and is no longer shiny, it's time to start stapling it down.
4. I start stapling the paper to the gatorboard along the outer edges of the paper. First I put a staple in the middle of one of the shorter sides of the paper. Then I turn the board around, pull on the opposite side until the paper is taut, and put a staple directly across the page from the first one. When pulling the paper tight, I tug on it just enough to see it strain against the staple. If you pull more, it will tear the staple out. Next, I repeat the process on the longer two sides of the paper, starting in the middle of one side, then pulling taut and doing the opposite staple. I do the corners next, using the same process of pulling the paper taut each time. It's a bit like stretching a canvas or even something like a drum.
If by the time I've stapled the centers of all four sides and corners, one of the first staples needs to be adjusted, I just pull it out with my fingernails, pull the page taut, and put another staple in. For a large piece of paper, I'll often do 3 staples in the middle of each side before moving onto the corners, such as in the drawing below.
Once the centers and corners are finished, I simply go around the rest of the paper edges with my stapler, placing staples about 1/2-inch apart al the way around the page. If I do them too far apart, sometimes wrinkles/buckles will pop up between staples as the paper is drying and that's frustrating.
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5. Next I just have to let the paper dry completely before it's ready to use. This can be sped up with a hair dryer, if desired. Don't try to draw on it until it's completely dried!
6. For a finishing touch, I tape the edges of my paper with masking or artist's tape, covering the edge of the paper and all the staples. This keeps water and paint from running under the paper while I'm painting, and also makes a nice clean edge all around my painting when I am done. When I finish painting, I simply remove the tape, pull the paper off the board, and remove the staples. (You can remove the staples first if it's easier. I have a tool that makes it easier to remove them after taking the paper off the board.)
Happy painting! Leave your comments or questions below... don't be shy! I want to hear from you!
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