Choosing the right type of pencil to use for sketching out the design of a watercolor painting can feel like a big deal. Choose wrong and you could end up with visible pencil lines you never intended.
The best type of pencil to use for watercolor painting is a sketching pencil with hard lead, generally between F and 4H. If you choose a pencil that is too soft, it will be hard to erase before watercoloring. If you choose a pencil that is too hard, it could damage your paper or be hard to see.
There are a number of things to consider when choosing a sketching pencil to use for your watercolor paintings. Let’s dive into them.
Choose a Pencil with Lead that Isn’t Too Soft or Too Hard
If you plan to erase your pencil lines from your watercolor painting, choose a pencil that isn’t too soft or too hard. A happy medium pencil within the range of F and 4H will be soft enough that it will be visible and won’t damage your paper, but also won’t be so soft that it’s difficult to erase.
Personally, I prefer a 4H pencil for sketching out my watercolor paintings. For me, this is my happy medium pencil that I have the easiest time working with.
It’s important to find your own happy medium pencil. Generally, I suggest searching within the range of F and 4H pencils.
If you choose a pencil that’s too soft, it will be really tricky to achieve light lines that you can easily erase later.
Also, if you’re using a rough watercolor paper instead of a hot-pressed watercolor paper, you may find that the graphite of a soft pencil sticks too easily in the nooks and crannies of your paper.
On the other hand, a hard pencil can cause problems too. Firstly, light lines drawn with a hard pencil can be hard to see. What’s the point of sketching before painting if you can’t see it?
So, you push harder with your pencil. Now the lines are visible, but your soft watercolor paper is now suffering. Depending on the watercolor paper you’re using, it might be too soft to withstand a harsh, hard pencil.
Make sure you’re not leaving indents in your paper when sketching because your pencil is too hard.
That’s why I like to stay within the F and 4H range. Personally, I prefer the harder end of that spectrum and usually go with a 4H pencil. It’s easy for me to draw lightly with it while still seeing my lines and without damaging my paper.
Alright, so even though we have our pencil choice figured out, there are still some other factors we’ll want to consider when sketching out a watercolor painting.
Use a Lightbox to Transfer Your Sketch to Your Watercolor Paper
If you plan to erase your pencil lines from your watercolor painting, have as few pencil lines as possible. A lightbox is great for transferring a sketch onto your watercolor paper once it’s finalized and only includes the bare minimum amount of lines needed to complete your watercolor painting.
Sketching can be a messy, fun, creative, and iterative process. As it should be! A great sketch includes a lot of mistakes, ideas, and trials.
This is great for the creative art process, but it’s not great for outlining a watercolor painting without leaving marks.
This is where a lightbox comes in.
Whenever I do a watercolor painting, I grab a piece of sketch paper and draw to my heart’s content. I get all of my ideas out and land on a finalized sketch I want to use.
Then, I pull out my lightbox and carefully transfer the bare minimum of my sketch onto my watercolor paper.
I’ll have my original sketch next to me as a reference while I work, so I don’t need to worry about transferring all of the minute details onto my watercolor paper. I simply transfer the essential shapes and items I’ll need to watercolor paper to complete my painting.
During this time, I’m careful to sketch really lightly on my watercolor paper and erase as little as possible.
This process really limits the amount of damage I do to my watercolor paper and the amount of pencil marks I need to grapple with.
Outline Your Watercolor Painting in Ink
If you’re dealing with stubborn pencil marks, or don’t want to worry about your pencil marks, embrace the style of combining watercolor and ink. There are some beautiful watercolor paintings that celebrate outlines by making them an important part of the piece.
Outlining a watercolor painting in ink can give you beautiful results. If you have a sketch that’s giving you trouble because the pencil lines are stubborn and hard to erase, consider working with them instead of fighting them.
Grab some awesome Micron pens and see if outlining your watercolor painting can lead to some artistic beauty you weren’t expecting.
Use Watercolor Pencils
If you already have a very good understanding of the colors and shading you’re planning to use, watercolor pencils can be a great option for outlining your work with pencils that will essentially disappear as they become integrated into the other paints you’re using.
Watercolor pencils are really neat because they start as pencils but, as you start painting, they turn into watercolors. You’ll have no pencil marks to worry about because your “pencil lines” will turn into watercolor paint.
That said, this can be a risky technique. You need to be very certain of the colors and shading you plan to use for your finished watercolor painting because you are essentially sketching and painting at the same time.
If you end up with a heavy watercolor pencil line in a place that’s supposed to be light, it can be tricky to rectify.
Practice with your watercolor pencils so that you understand them well. Once you do, they can be a great option for watercoloring without leaving marks.
Diana has been an artist for over 25 years and has training in drawing, painting, digital drawing and graphic design. Diana’s latest obsession is digitally drawing with Procreate and creating t-shirt designs with Canva. Diana has experience selling her art across a number of platforms and loves helping other artists learn how to make money from their art as well.